Semiconductor device and manufacturing method for semiconductor device

0001Related to a semiconductor device having a circuit including a semiconductor element such as a transistor and a method for manufacturing the same. .. For example, power devices, memories, thyristors, converters, a Semiconductor integrated circuits including image sensors, electro-optic devices represented by liquid crystal display panels, The present invention relates to an electronic device equipped with a light emitting display device or the like having an optical element as a component.

0002In the present specification, a semiconductor device is a device that can function by utilizing semiconductor characteristics. Refers to the whole, electro-optic devices, light emission display devices, semiconductor circuits and electronic devices are all semiconductor devices. is there.

0003As represented by liquid crystal display devices, transistors formed on glass substrates and the like are amorpha. It is composed of silicon, polycrystalline silicon, etc. Using amorphous silicon Although the transistor has low field-effect mobility, it can handle a large area of the glass substrate. Wear. In addition, although the field-effect mobility of transistors using polycrystalline silicon is high, it is a glass substrate. It has the disadvantage that it is not suitable for increasing the area of.

0004A transistor is manufactured using an oxide semiconductor as opposed to a transistor using silicon. Technology applied to electronic devices and optical devices is attracting attention. For example, as an oxide semiconductor Then, a transistor was manufactured using zinc oxide and In-Ga-Zn-O oxide, and a display device was used. Patent Document 1 and Patent Document 2 disclose techniques used for switching elements of pixels of the above. To.

<p num="0005"><patcit num="1"><text>JP-A-2007-123861</text></patcit><patcit num="2"><text>Japanese Unexamined Patent Publication No. 2007-96055</text></patcit></p>

<p num="0006">The electrical characteristics of the transistor are such that the oxide semiconductor film, which is the active layer, is in contact with the oxide semiconductor film. It is easily affected by the interface with the gate insulating film. During or after the transistor is manufactured The interface between the oxide semiconductor film and the gate insulating film, that is, the interface on the gate electrode side is amorphous. In the quality state, the structural state is likely to fluctuate due to the influence of temperature in the manufacturing process, and the tiger The electrical characteristics of the engineer tend to be unstable.</p><p num="0007">In addition, a transistor using an oxide semiconductor film as a channel irradiates visible light or ultraviolet light. The electrical characteristics change with and.</p><p num="0008">In view of such a problem, one aspect of the present invention is in contact with an oxide semiconductor film and the oxide semiconductor film. A semiconductor device having a transistor having a good interface with the gate insulating film and a method for manufacturing the same. Providing is one of the issues. Transis using an oxide semiconductor film as a channel One of the challenges is to provide stable electrical characteristics to the data and to manufacture highly reliable semiconductor devices. To do. In addition, a large number of highly reliable semiconductor devices are used using a large substrate such as mother glass. One of the issues is to provide a manufacturing process of a semiconductor device capable of production.</p>

<p num="0009">One aspect of the present invention is an insulating film (gate insulating film) in contact with an oxide semiconductor film and the oxide semiconductor film. High crystallinity at least near the interface of the oxide semiconductor film in order to improve the interface with Form a small area. This creates a semiconductor device with stable electrical characteristics and high reliability. Can be made.</p><p num="0010">In addition, as a method for improving the crystallinity of the oxide semiconductor film, a part of the oxide semiconductor film is used. An oxide semiconductor film having a second crystal structure may be provided. The second crystal structure is the wurtzite type It is the crystal structure of. The oxide semiconductor film that can be the second crystal structure becomes the first crystal structure. Compared with the oxide semiconductor film, it is easy to crystallize by heat treatment and has high crystallinity. No. The crystal structure of 1 is a non-wurtzite structure, YbFe₂O₄Type structure, Yb₂Fe₃O₇Mold structure and It is a crystal structure selected from any one of the modified structures of.</p><p num="0011">In addition, an oxide semiconductor film that can become the first crystal structure by heat treatment and a second oxide semiconductor film that can become the first crystal structure by heat treatment. By laminating and forming an oxide semiconductor film that can have a crystal structure of Therefore, the oxide semiconductor film, which is the second crystal structure, is used as a seed, and the first crystal structure is heat-treated. The oxide semiconductor film that can be used as a crystal grows, and the oxide semiconductor film that is the first crystal structure is formed. Is done.</p><p num="0012">The heat treatment is performed at 150 ° C. or higher and 650 ° C. or lower, preferably 200 ° C. or higher and 500 ° C. or lower. ..</p><p num="0013">Also, instead of heat treatment for crystallization, acid is applied by sputtering while heating. A compound semiconductor film can be formed.</p><p num="0014">Based on the above, for example, in an oxide semiconductor laminate in which an oxide semiconductor film is laminated, at least By providing a layer having a second oxide semiconductor film, the oxide semiconductor laminate is heated. By doing this, an oxide semiconductor film with high crystallinity can be obtained.</p><p num="0015">The film thickness of the second oxide semiconductor film is 1 atomic layer or more and 10 nm or less, preferably 2 nm or more. The upper 5 nm or less.</p><p num="0016">In the above configuration, the oxide semiconductor film is a non-single crystal, and the entire oxide semiconductor film is in an amorphous state. Crystals having at least c-axis orientation in the oxide semiconductor film instead of (amorphous state) Have.</p><p num="0017">One aspect of the present invention is a method for manufacturing a semiconductor device having a transistor, and the first aspect is on an insulating surface. After forming the oxide semiconductor film of 1, then forming the second oxide semiconductor film, the first heating process is performed. The oxide semiconductor film having the first crystal structure and the oxide semiconductor having the second crystal structure Form a film. Next, on the oxide semiconductor film having the second crystal structure, the third oxide semiconducting After forming the body film, a second heat treatment is performed to form an oxide semiconductor film having a third crystal structure. An oxide semiconductor film having a first crystal structure, an oxide semiconductor film having a second crystal structure, And a laminate of oxide semiconductor films having a third crystal structure is used as the channel region of the transistor. It is characterized in that it is formed.</p><p num="0018">The oxide semiconductor film having the first crystal structure and the oxide half having the third crystal structure are described above. The crystal structure of the conductor film is YbFe₂O₄Type structure, Yb₂Fe₃O₇Mold structure and non-wurtrite type The crystal structure of the oxide semiconductor film which is any one of the structures and has the second crystal structure is c. It is a Ruth ore type structure.</p><p num="0019">The temperature of the first heat treatment and the second heat treatment is 150 degrees or more and 650 degrees or less, preferably 2 It is 00 degrees or more and 500 degrees or less. For this reason, mother glass, which is a large-area substrate, is used as the substrate. Can be used.</p><p num="0020">The oxide semiconductor film having the first crystal structure to the oxide semiconductor film having the third crystal structure is It is a non-single crystal, and the entire oxide semiconductor film is not in an amorphous state (amorphous state). It has a c-axis oriented crystal region. That is, it has an amorphous region and a crystal region with c-axis orientation.</p><p num="0021">Since the oxide semiconductor film having the second crystal structure has a wurtzite type crystal structure, the first Compared with an oxide semiconductor film having a crystal structure and an oxide semiconductor film having a third crystal structure , Easy to crystallize by heat treatment and high crystallinity. Also, an acid having a second crystal structure The compound semiconductor film has a hexagonal bond in the plane on the ab plane. Also, six Layers with square bonds are laminated and bonded in the film thickness direction (c-axis direction), and are c-axis oriented. There is. Therefore, an oxide semiconductor film having a second crystal structure having a wurtzite type crystal structure The first oxide semiconductor film and the third oxide semiconductor film are crystal-grown by heating. The crystal axis of the oxide semiconductor film having a second crystal structure having a wurtzite type crystal structure. The oxide semiconductor film having the first crystal structure and the third crystal structure are formed so as to be substantially the same as. It is possible to form an oxide semiconductor film having. Oxide semiconductor film having a first crystal structure , And the oxide semiconductor film having the third crystal structure is an oxide semiconductor having the second crystal structure. Like the film, it has a hexagonal bond in the plane on the ab plane. Also hexagon Layers with the above bonds are laminated and bonded in the film thickness direction (c-axis direction), and are c-axis oriented. ..</p><p num="0022">Further, a gate insulating film is formed on the oxide semiconductor laminate, and a gate electric voltage is formed on the gate insulating film. A transistor can be manufactured by forming a pole. As a result, with the gate insulating film Since the oxide semiconductor laminate has high crystallinity and high uniformity at the interface between the two, the electrical characteristics are low. It is possible to obtain a transistor that is constant and highly reliable.</p><p num="0023">Further, a gate insulating film is formed on the gate electrode, and the oxide semiconductor laminate is formed on the gate insulating film. By forming the above, a transistor can be manufactured. As a result, with the gate insulating film At the interface, the oxide semiconductor laminate has high crystallinity and high uniformity, so that it has excellent electrical characteristics. A stable and highly reliable transistor can be obtained.</p><p num="0024">Also, an oxide having a hexagonal bond on the ab plane and a crystal region oriented on the c-axis. By using a laminate of semiconductor films in the channel region of the transistor, the transistor is illuminated. Transistor thresholds before and after firing, or before and after the bias-heat stress (BT) test It is possible to manufacture a transistor with stable electrical characteristics with a small amount of change in voltage. it can.</p>

<p num="0025">According to one aspect of the present invention, the boundary between the oxide semiconductor film and the gate insulating film in contact with the oxide semiconductor film. A semiconductor device having a transistor having a good surface condition can be manufactured. Also stable It is possible to manufacture a semiconductor device having electrical characteristics. Also like mother glass A highly reliable semiconductor device can be mass-produced by using a large substrate.</p>

0026<figref num="1">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="2">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="3">The figure explaining the crystal structure which concerns on embodiment of this invention.</figref><figref num="4">The figure explaining the crystal structure which concerns on embodiment of this invention.</figref><figref num="5">HAADF-STEM image illustrating the crystal structure according to the embodiment.</figref><figref num="6">HAADF-STEM image illustrating the crystal structure according to the embodiment.</figref><figref num="7">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="8">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="9">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="10">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="11">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="12">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="13">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="14">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="15">It is a top view and sectional view explaining the semiconductor device which is one aspect of this invention.</figref><figref num="16">It is sectional drawing explaining the manufacturing method of the semiconductor device which is one aspect of this invention.</figref><figref num="17">It is sectional drawing explaining the semiconductor device which is one aspect of this invention .</figref><figref num="18">It is a block diagram and a circuit diagram which show one aspect of this invention.</figref><figref num="19">It is sectional drawing which shows one aspect of this invention.</figref><figref num="20">It is a figure which shows one aspect of an electronic device.</figref>

0027Embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is described below. Various forms and details without departing from the spirit and scope of the present invention. It is easily understood by those skilled in the art that it can be changed to. Therefore, the present invention is carried out as shown below. It is not construed as being limited to the description in the form of. The structure of the present invention described below. In the process, the same reference numerals are used for the same parts or parts having similar functions between different drawings. It will be used throughout, and the description of its repetition will be omitted.

0028In addition, in each figure described in this specification, the size of each composition, the thickness of a film, or a region is clarified. May be exaggerated for clarity. Therefore, it is not necessarily limited to that scale. ..

0029In addition, terms such as 1, 2, and 3 used in this specification are used to avoid confusion of components. It is attached to, and is not limited in number. Therefore, for example, "first" is changed to "" It can be explained by replacing it with "second" or "third" as appropriate.

0030(Embodiment 1) In the present embodiment, a transistor using an oxide semiconductor film on the insulating surface as a channel and a transistor thereof. The method of producing the above will be described with reference to FIGS. 1 and 2. Figure 1 (B) shows the configuration of the semiconductor device. It is a cross-sectional view for explaining the structure of a transistor which is one form, and is one of FIG. 1 (A) which is a top view. Corresponds to the cross-sectional view of the dotted line AB. In addition, in FIG. 1 (A), the substrate 101 and oxide insulation The film 102, the gate insulating film 107, and the insulating film 109 are omitted. Figure 2 shows Figure 1 (B). It is sectional drawing explaining the manufacturing process of the transistor shown in FIG.

0031The transistor shown in FIG. 1 (B) has an oxide insulating film 102 formed on the substrate 101 and an acid. The oxide semiconductor laminate 105 formed on the compound insulating film 102 and the oxide semiconductor laminate 10 A pair of electrodes 106 that function as source and drain electrodes formed on 5 and oxidation A game formed on the material insulating film 102, the oxide semiconductor laminate 105, and the pair of electrodes 106. G. Overlapping with the oxide semiconductor laminate 105 via the insulating film 107 and the gate insulating film 107. It has an electrode 108. Insulation that covers the gate insulating film 107 and the gate electrode 108. It may have a membrane 109.

0032The oxide semiconductor laminate 105 is oxidized having a first crystal structure in contact with the oxide insulating film 102. A second object in contact with the semiconductor film 105a and the oxide semiconductor film 105a having the first crystal structure. It is characterized in that an oxide semiconductor film 105b having a crystal structure is laminated.

0033Further, the oxide semiconductor film 105b having the second crystal structure is used as a seed crystal, and the first crystal structure is used. The oxide semiconductor film 105a having the above is characterized by crystal growth.

0034The oxide semiconductor film 105b having a second crystal structure is a trigonal crystal and / or a hexagonal crystal. To.

0035That is, the oxide semiconductor film having the second crystal structure and the first crystal structure are both trigonal and trigonal. / Or since it is a hexagonal crystal, a hexagonal lattice image can be confirmed from the c-axis direction.

0036The oxide semiconductor film 105a having the first crystal structure and the oxide having the second crystal structure Each of the semiconductor films 105b is a non-single crystal, and the entire oxide semiconductor film is in an amorphous state ( It has a c-axis oriented crystal region instead of (amorphous state).

0037Next, the method of manufacturing the transistor shown in FIG. 1 (B) will be described with reference to FIG.

0038As shown in FIG. 2 (A), after forming the oxide insulating film 102 on the substrate 101, oxide insulation is performed. A first oxide semiconductor film 103a is formed on the film 102, and the first oxide semiconductor film 103a is formed. A second oxide semiconductor film 103b is formed on the surface.

0039The substrate 101 must have at least enough heat resistance to withstand the subsequent heat treatment. It will be important. When using a glass substrate as the substrate 101, use one with a distortion point of 730 degrees or more. It is preferable to have. For the glass substrate, for example, aluminosilicate glass, aluminosilicate Glass materials such as silicate glass and barium borosilicate glass are used. In addition, B₂O₃It is preferable to use a glass substrate containing a larger amount of BaO. For mass production, the basis Board 101 is the 8th generation (2160mm x 2460mm), 9th generation (2400mm x 280) 0mm or 2450mm x 3050mm), 10th generation (2950mm x 3400m) It is preferable to use a mother glass such as m). Mother glass has a high processing temperature and is processed If you use mother glass for mass production, it will shrink significantly if the time is long. It is desirable that the heat treatment is 600 degrees or less, preferably 450 degrees or less.

0040Instead of the above glass substrate, ceramic substrate, quartz substrate, sapphire substrate, etc. A substrate made of an edge body can be used. In addition, crystallized glass or the like can be used. .. Furthermore, the surface of a semiconductor substrate such as a silicon wafer or the surface of a conductive substrate made of a metal material. An insulating film formed on the surface may also be used.

0041When a glass substrate containing impurities such as alkali metal is used as the substrate 101, A nitride insulating film is used between the substrate 101 and the oxide insulating film 102 to prevent the intrusion of potassium metal. A silicon nitride film, an aluminum nitride film, or the like may be formed. Nitride insulating film is CVD It can be formed by a method, a sputtering method, or the like. Lithium, sodium, potassium, etc. Alkali metal is an impurity of the oxide semiconductor film formed later, so the content is reduced. Is preferable.

0042The oxide insulating film 102 is formed by using an oxide insulating film that releases a part of oxygen by heating. .. As an oxide insulating film that releases a part of oxygen by heating, it is better than oxygen that satisfies the stoichiometric ratio. It is preferable to use an oxide insulating film containing a large amount of oxygen. Part of oxygen is released by heating The oxide insulating film to be formed is the first oxide semiconductor film 103a and the second oxide semiconductor by heating. Oxygen can be diffused into the membrane 103b. The oxide insulating film 102 is typically oxidized. Silicon, Silicon Nitride, Silicon Nitride, Aluminum Oxide, Aluminium Oxide It can be formed of um, gallium oxide, hafnium oxide, yttrium oxide, or the like.

0043An oxide insulating film containing more oxygen than oxygen that satisfies the stoichiometric ratio is a part of oxygen when heated. Releases. The amount of oxygen released at this time is TDS (Thermal Desorptio). n Spectrocopy: Acid converted to oxygen atom in analysis The amount of elementary release is 1.0 × 10¹⁸atoms / cm³Above, preferably 1.0 × 10²⁰a toms / cm³Above, more preferably 3.0 × 10²⁰atoms / cm³That's all ..

0044Here, about the method of measuring the amount of oxygen released when converted to oxygen atoms by TDS analysis. , Will be described below.

0045The amount of gas released during TDS analysis is proportional to the integral value of the spectrum. Therefore, oxidation The amount of gas released by the integral value of the spectrum of the material insulating film and the ratio of the standard sample to the reference value. Can be calculated. The reference value of a standard sample is the spectrum of a sample containing a predetermined atom. It is the ratio of the density of atoms to the integral value of.

0046For example, TDS analysis results of a silicon wafer containing hydrogen of a predetermined density, which is a standard sample, and From the TDS analysis results of the oxide insulating film, the amount of oxygen molecules released from the oxide insulating film (N (O)₂)) Can be calculated by Equation 1. Here, it is detected by the mass number 32 obtained by TDS analysis. It is assumed that all of the spectra are derived from oxygen molecules. CH as having a mass number of 32₃OH is However, it is not considered here as it is unlikely to exist. Also, with isotopes of oxygen atoms Oxygen molecules containing an oxygen atom with a mass number of 17 and an oxygen atom with a mass number of 18 are also natural. It is not considered because the abundance ratio in the world is extremely small.

0047N (O₂) = N (H)₂) / S (H)₂) × S (O₂) × α (number 1)

0048N (H₂) Is the value obtained by converting the hydrogen molecule desorbed from the standard sample by the density. S (H₂) Is , It is the integral value of the spectrum when the standard sample is TDS analyzed. Here, the standard of the standard sample Set the value to N (H)₂) / S (H)₂). S (O₂) Said that the oxide insulating film was analyzed by TDS. It is the integral value of the spectrum. α is responsible for affecting spectral intensity in TDS analysis It is a number. For details of Equation 1, refer to Japanese Patent Application Laid-Open No. 6-275697. In addition, it should be noted. The amount of oxygen released from the oxide insulating film is the temperature-temperature desorption analyzer EMD-W manufactured by Electronic Science Co., Ltd. Using A1000S / W, 1 × 10 as standard sample¹⁶atoms / cm³Hydrogen atom Measure using a silicon wafer containing.

0049Also, in TDS analysis, some of the oxygen is detected as oxygen atoms. Oxygen molecule and oxygen source The ratio of offspring can be calculated from the ionization rate of oxygen molecules. The above α is the oxygen content. Since it includes the ionization rate of the child, the amount of oxygen atom released can be determined by evaluating the amount of oxygen molecule released. Even so, it can be estimated.

0050In addition, N (O₂) Is the amount of oxygen molecules released. In the oxide insulating film, converted to oxygen atoms The amount of oxygen released at this time is twice the amount of oxygen molecules released.

0051The oxide insulating film 102 is 50 nm or more, preferably 200 nm or more and 500 nm or less. .. By thickening the oxide insulating film 102, the amount of oxygen released from the oxide insulating film 102 is increased. The boundary between the oxide insulating film 102 and the oxide semiconductor film formed later. It is possible to reduce defects on the surface.

0052The oxide insulating film 102 is formed by a sputtering method, a CVD method, or the like. By heating The oxide insulating film that releases a part of oxygen is easy to form by using the sputtering method. Therefore, it is preferable.

0053When forming an oxide insulating film in which a part of oxygen is released by heating by the sputtering method , The amount of oxygen in the film-forming gas is preferably high, and oxygen, or a mixed gas of oxygen and a rare gas, etc. Can be used. Typically, the oxygen concentration in the film-forming gas is 6% or more and 100% or less. Is preferable.

0054The first oxide semiconductor film 103a is trigonal and / or hexagonal by heating and is the first. It is formed using an oxide semiconductor film that can have a crystal structure.

0055The first oxide semiconductor film 103a is In-Sn-Ga-, which is an oxide of a quaternary metal. Zn-O film, In-Ga-Zn-O film, which is an oxide of ternary metal, In-Sn-Zn- O film, In-Al-Zn-O film, Sn-Ga-Zn-O film, Al-Ga-Zn-O film, S n-Al-Zn-O film, In-Zn-O film, which is an oxide of binary metal, Sn-Zn-O A film, an Al-Zn-O film, an In-Ga-O film, or the like can be used. In addition, the above oxide SiO for semiconductors₂May include. Here, for example, the In-Ga-Zn-O film is an in-Ga-Zn-O film. It is an oxide film having gallium (In), gallium (Ga), and zinc (Zn).

0056The first oxide semiconductor film 103a is trigonal and / or hexagonal and non-tetragonal by heating. Wurtzite type, YbFe₂O₄Type structure, Yb₂Fe₃O₇Mold structure and its modified structure It is formed using an oxide semiconductor film that can have one of the crystal structures.

0057As an example of an oxide semiconductor film having a first crystal structure, In-G, which is an oxide of a ternary metal. The a-Zn-O membrane has trigonal and / or hexagonal non-wurtzite crystals. Also, three yuan YbFe is used for the In-Ga-Zn-O film, which is an oxide of the based metal.₂O₄InG which is a type structure aZnO₄Or Yb₂Fe₃O₇In₂Ga₂ZnO₇Etc., and its deformation Can take a mold structure (M. Nakamura, N. Kimizuka, and T. Mohri, "The Phase Relations in the In₂O₃-Ga₂ZnO₄-ZnO System at 1350 degrees ", J. Soli d State Chem., 1991, Vol.93, p.298-315). It should be noted that , YbFe₂O₄The mold structure is AB, where the layer containing Yb is the A layer and the layer containing Fe is the B layer. It has a repeating structure of B | ABB | ABB |, and its modified structure is, for example, ABBB. The repeating structure of | ABBB | can be mentioned. Also, Yb₂Fe₃O₇The mold structure is It has a repeating structure of ABB | AB | ABB | AB |, and its modified structure is, for example, List the repeating structures of ABBB | ABB | ABBB | ABB | ABBB | ABB | Can be done.

0058As the first oxide semiconductor film 103a, 1 × 10 is added to the metal oxide.¹⁷/cm³After Top 5x10¹⁹/cm³It may contain less than nitrogen.

0059The metal oxide that can be formed as the first oxide semiconductor film 103a is Eneru. The ghee gap is 2 eV or more, preferably 2.5 eV or more, more preferably 3 eV or more. To. In this way, by using an oxide semiconductor with a wide energy gap, a transistor Off current can be reduced.

0060The second oxide semiconductor film 103b is an oxide semiconductor film that can become a second crystal structure by heating. Is formed using. Oxide semiconductor films that can have a second crystal structure are trigonal and / or hexagonal. Compared to an oxide semiconductor film that can be the first crystal structure of crystals, it is easier to crystallize by heat treatment. It is also highly crystalline.

0061As the second oxide semiconductor film 103b, zinc oxide, an oxynitride semiconductor, or the like can be used. Wear. The oxynitride semiconductor is a metal oxide listed in the first oxide semiconductor film 103a, 5 × Ten¹⁹/cm³It can be formed by adding nitrogen of 7 atomic% or more.

0062The second oxide semiconductor film 103b is used for crystal growth of the first oxide semiconductor film 103a. Since it is used as a seed, the thickness may be set to the thickness at which crystals grow, and typically one atomic layer or more is 10n. It may be m or less, preferably 2 nm or more and 5 nm or less. Thickness of Second Oxide Semiconductor Film 103b The throughput in the film formation treatment and the heat treatment can be increased by reducing the thickness.

0063The first oxide semiconductor film 103a and the second oxide semiconductor film 103b are sputtered, respectively. It can be formed by a ring method, a coating method, a printing method, a pulse laser vapor deposition method, or the like. spa The first oxide semiconductor film 103a and the second oxide semiconductor film 103b are formed by the tattering method. When forming a film, use either an AC sputtering device, a DC sputtering device, or an RF sputtering device. Use one of the sputtering equipment.

0064The second oxide semiconductor film 103b is formed of an oxynitride semiconductor by a sputtering method. In this case, after forming the first oxide semiconductor film 103a, it is introduced into the sputtering apparatus. An oxynitride semiconductor can be formed by switching the type of nitrogen, that is, by introducing nitrogen. .. That is, the first oxide semiconductor film 103a and the second oxide semiconductor film 103b are continuously formed. It can be produced and has excellent mass productivity.

0065Next, the first heat treatment is performed. The first heat treatment temperature is preferably 150 degrees or more and 650 degrees or less. It is 200 degrees or more and 500 degrees or less. In addition, the heating time of the first heat treatment is 1 minute or more 2 4 hours or less. After gradually raising the temperature of the first heat treatment, it is set to a constant temperature. May be good. By setting the temperature rise rate from 500 degrees or more to 0.5 degrees / h or more and 3 degrees / h or less As the second oxide semiconductor film 103b gradually grows into crystals, the crystallinity can be further improved. it can.

0066In the first heat treatment, a noble gas (typically argon) atmosphere, an oxygen atmosphere, and a nitrogen atmosphere Surrounding air, dry air atmosphere, or mixed atmosphere of noble gas (typically argon) and oxygen, Alternatively, it is preferable to use a mixed atmosphere of rare gas and nitrogen. Specifically, hydrogen, etc. A high-purity gas atmosphere in which impurities have been removed to a few ppm or a few ppb. Is preferable.

0067The heat treatment device used for the first heat treatment is not particularly limited, and heat from a heating element such as a resistance heating element is used. A device for heating the object to be processed by conduction or heat radiation may be provided. For example, electricity Furnace, GRTA (Gas Rapid Thermal Anneal) equipment, LRTA RTA (Rapid) for (Lamp Rapid Thermal Anneal) equipment, etc. Thermal Anneal) equipment can be used. The LRTA device is a haloge Lamps, metal halide lamps, xenon arc lamps, carbon arc lamps, high pressure By radiation of light (electromagnetic waves) emitted from lamps such as sodium lamps and high-pressure mercury lamps A device that heats an object to be processed. The GRTA device is a device that performs heat treatment using high-temperature gas. It is a place.

0068By the first heat treatment, the surface of the second oxide semiconductor film 103b to the first oxide semiconductor film Crystal growth begins toward 103a. The second oxide semiconductor film 103b is easily crystallized. Therefore, all of the second oxide semiconductor film 103b crystallizes, and the oxide half having the second crystal structure It becomes a conductor film 104b. Further, from the surface of the second oxide semiconductor film 103b to the first oxide half Since the crystal grows toward the conductor film 103a, it becomes a c-axis oriented crystal region. That is, the second The oxide semiconductor film 104b having a crystal structure has a hexagonal shape on the upper plane on the ab plane. There is an eggplant bond. In addition, layers with hexagonal bonds are laminated in the film thickness direction (c-axis direction). They are combined and c-axis oriented.

0069By subsequently performing the first heat treatment, the oxide semiconductor film 104b having the second crystal structure is formed. As a seed, the crystal growth of the first oxide semiconductor film 103a is an oxide having a second crystal structure. It proceeds from the interface with the semiconductor film 104b toward the oxide insulating film 102. Has a second crystal structure Since the oxide semiconductor film 104b is oriented in the c-axis direction, it has a second crystal structure. By using the oxide semiconductor film 104b as a seed, the oxide semiconductor film 10 having a second crystal structure is used. The first oxide semiconductor film 103a is crystal-grown so as to be substantially the same as the crystal axis of 4b. be able to. That is, the first oxide semiconductor film 103a is crystal-grown while being c-axis oriented. It is possible. That is, the oxide semiconductor film 104a having the first crystal structure is ab. Hexagonal connections are made on the upper plane of the plane. Also, a layer with hexagonal bonds Are laminated and bonded in the film thickness direction (c-axis direction), and are c-axis oriented. By the above process Therefore, an oxide semiconductor film 104a having a first crystal structure oriented with a c-axis can be formed. (See Figure 2 (B)).

0070By the first heat treatment, crystals are formed in the direction perpendicular to the surface of the second oxide semiconductor film 103b. When grown, it has an oxide semiconductor film 104a having a first crystal structure and a second crystal structure. The c-axis of the oxide semiconductor film 104b is approximately vertical to the surface.

0071Further, by the first heat treatment, the first oxide semiconductor film 103a and the second oxide semiconducting material are obtained. As the hydrogen contained in the body membrane 103b is released (that is, dehydrogenated and dehydrated), the acid Part of the oxygen contained in the compound insulating film 102 is the first oxide semiconductor film 103a and the second acid. Of the compound semiconductor film 103b and the first oxide semiconductor film 103a in the oxide insulating film 102 Diffuses near the interface. By this step, the first oxide semiconductor film 103a and the second oxidation Oxygen defects contained in the semiconductor film 103b can be reduced, and the oxide insulating film can be reduced. Oxide by diffusing oxygen in the vicinity of the first oxide semiconductor film 103a in 102 By reducing defects at the interface between the insulating film 102 and the first oxide semiconductor film 103a. Wear. As a result, the oxide semiconduct with the first crystal structure with reduced hydrogen concentration and oxygen defects It is possible to form a body film 104a and an oxide semiconductor film 104b having a second crystal structure. To.

0072The first oxide semiconductor film 103a and the second oxide semiconductor film by the sputtering method. When forming 103b, the leak rate in the processing chamber of the sputtering equipment is set to 1 × 10.^-10Pa m³By setting it to / sec or less, the first oxidation during film formation by the sputtering method Alkali metals, hydrogen, etc. in the semiconductor film 103a and the second oxide semiconductor film 103b It is possible to reduce the mixing of impurities. Also, as an exhaust system, an adsorption type vacuum pump (for example, By using a cryopump, etc.), the backflow of impurities such as alkali metals and hydrogen from the exhaust system Can be reduced.

0073Further, when the first oxide semiconductor film 103a and the second oxide semiconductor film 103b are formed. , Gas introduced into the processing chamber of the sputtering equipment, such as nitrogen gas, oxygen gas, and algo The film may be formed by introducing the gas in a heated state. As a result, the first oxide half To reduce the hydrogen content in the conductor film 103a and the second oxide semiconductor film 103b. Can be done.

0074Further, the first oxide semiconductor film 103a and the second oxide semiconductor film are obtained by the sputtering method. Included on or inside the sputtering equipment, target, before filming 103b Preheating may be performed to remove water or hydrogen. As a result, the first acid Reduce the hydrogen content in the compound semiconductor film 103a and the second oxide semiconductor film 103b Can be

0075From the above steps, the oxide semiconductor film 104a having the first crystal structure and the second crystal structure can be obtained. The oxide semiconductor film 104b can be formed. In addition, hydrogen is contained in the oxide semiconductor. If it is included, a part of it becomes a donor and an electron as a carrier is generated. Also, Similarly, oxygen defects in oxide semiconductors also become donors and generate electrons as carriers. .. Therefore, the oxide semiconductor film 104a having the first crystal structure has the second crystal structure. By reducing the hydrogen concentration and oxygen defects in the oxide semiconductor film 104b, the catalyst in the oxide semiconductor can be reduced. The rear concentration can be reduced, and the threshold voltage minor of the transistor to be manufactured later The shift can be reduced.

0076&lt;Hexagonal crystal structure&gt; Here, the hexagonal crystal structure will be described below.

0077First, the c-axis oriented second crystal structure will be described with reference to FIG. C-axis oriented second Regarding the crystal structure, the structure on the ab plane seen from the c-axis direction is shown in Fig. 3 (A), and the c-axis direction is shown. The vertical structure is shown in Fig. 3 (B).

0078Examples of the crystal having the second crystal structure include zinc oxide, indium nitride, and gallium nitride. And so on. In addition, the nitrogen-containing oxide semiconductor, that is, the oxynitride semiconductor, is also c-axis oriented. It may be a film having a crystal structure.

0079Specifically, nitrogen is 5 × 10¹⁹/cm³Above, preferably 1 × 10²⁰/cm³Above 2 The In-Ga-Zn-O film containing less than 0 atomic% is a film having a second crystal structure oriented in the c-axis. In-O crystal plane (crystal plane containing indium and oxygen) and In-O crystal plane (indium) A layer having one layer of Ga and Zn is provided between the crystal plane containing oxygen and oxygen.

0080Next, the first crystal structure of the hexagonal system oriented with the c-axis will be described.

0081For example, nitrogen 1x10¹⁷/cm³Above 5 × 10¹⁹/cm³In-Ga-Z including less than The nO film is a film having a c-axis oriented hexagonal first crystal structure. C-axis oriented hexagon The In-Ga-Zn-O film having the first crystal structure of the crystal system has an In-O crystal plane on the ab plane. (Crystal plane containing indium and oxygen), between In-O crystal plane and In-O crystal plane Includes two layers with Ga and Zn. Two layers with Ga and Zn In, Ga and Zn need only be in one layer or both layers, and their positions are limited. I can't.

0082The second crystal structure and the first crystal structure are both hexagonal and are original in the ab plane. The child is located in a hexagon. Then, the first crystal structure of the hexagonal system is in contact with the second crystal structure, and six The first crystal structure of the square system matches the second crystal structure.

0083A second c-axis oriented hexagonal system with the same lattice constant on top of the c-axis oriented first crystal structure Figure 4 shows how the crystal structures of the above are matched. C-axis oriented hexagonal second crystal structure 200 0 is shown in FIG. 4 (A), and the c-axis oriented first crystal structure 2001 is shown in FIG. 4 (B). Also , The second crystal structure 2000 of the hexagonal system is in contact with the first crystal structure 2001, and the second crystal structure of the hexagonal system A schematic diagram in which the crystal structure 2001 of 1 matches the crystal structure 2000 of the second crystal is shown in FIG. 4 (C). Shown in.

0084In this way, the first crystal structure 2001 of the hexagonal system is in contact with the second crystal structure 2000, and the hexagonal crystal Crystallinity by matching the first crystal structure 2001 of the system with the second crystal structure 2000 As a seed crystal layer, a layer containing a second crystal structure 2000 oriented with a c-axis, which has a high value and is easy to crystallize. By forming the oxide semiconductor film in contact with the seed crystal layer, the oxide semiconductor film is formed. When the second crystal structure 2000 contained in the seed crystal layer facilitates the crystallization of the oxide semiconductor film It has the effect.

0085&lt;Seed crystal layer&gt; Next, the seed crystal layer will be described. The seed crystal layer contains a second crystal structure oriented on the c-axis. in particular For the seed crystal layer, a material having higher crystallinity than the oxide semiconductor film and easily crystallizing is used.

0086The c-axis oriented second crystal structure that can be used for the seed crystal layer will be described below.

0087Examples of compounds that have a c-axis oriented second crystal structure and can be used in the seed crystal layer are examples. For example, zinc oxide, indium nitride, gallium nitride and the like can be mentioned as examples. Also, 5x10 nitrogen¹⁹/cm³Above, preferably 1 × 10²⁰/cm³Includes more than 7 atomic% Oxide semiconductors may also be films containing a second crystal structure oriented on the c-axis.

0088When an oxide semiconductor containing nitrogen is used for the seed crystal layer, the nitrogen concentration is 5 × 10.¹⁹/cm³that's all , Preferably 1x10²⁰/cm³It is intentionally included so that it is more than 7 atomic%. Nitrogen Oxide semiconductor films intentionally containing elements in this range are oxidized without intentionally containing nitrogen. The energy gap is smaller than that of a physical semiconductor film, and carriers can easily flow.

0089HAADF (high-angle annula) with a second crystal structure oriented on the c-axis. r dark field)-Diffraction image in which bright spots appear alternately in the actual observation image of STEM May be observed.

0090Actual observation image of HAADF-STEM obtained by calculation based on the second crystal structure oriented on the c-axis Is shown in Fig. 5 (A).

0091In addition, HAADF- of an In-Ga-Zn-O film formed using a film-forming gas containing only nitrogen. The actual observation image of STEM is shown in Fig. 5 (B).

0092The actual observation images of HAADF-STEM shown in Fig. 5 (A) or Fig. 5 (B) have two cycles. It can be confirmed that it has a c-axis oriented second crystal structure having a sex layer structure.

0093The nitrogen-containing In-Ga-Zn-O film is a quartz glass substrate using a sputtering method. A film was formed on top with a thickness of 300 nm. As a target In: Ga: Zn = 1: 1: 1 [a Tom ratio] is used, the distance between the board and the target is 60 mm, and 0.5 using a DC power supply. A film was formed at a pressure of 0.4 Pa with a power of kw. In addition, the substrate temperature during film formation is set to 400 degrees. The sputtering gas was nitrogen only, and was flowed through the film forming chamber at a flow rate of 40 sccm.

0094&lt;Oxide semiconductor film&gt; Next, the oxide semiconductor film will be described. The oxide semiconductor film is a non-single crystal and is a half oxide. The entire conductor film is not in an amorphous state (amorphous state), but at least a c-axis oriented hexagonal crystal It contains the first crystal structure of the system and contains crystals that are anisotropically grown from the seed crystal layer. Half oxide Since the entire conductor film is not in an amorphous state (amorphous state), the electrical characteristics are unstable and amorphous. Formation is suppressed.

0095Regarding the first crystal structure having c-axis oriented anisotropy that can be used for oxide semiconductor films I will explain.

0096The first hexagonal crystal structure is YbFe.₂O₄Type structure, Yb₂Fe₃O₇Mold structure and And its modified structure can be mentioned as an example. For example, I, which is an oxide of a ternary metal n-Ga-Zn-O has a hexagonal first crystal structure and is used for oxide semiconductor films. Can be done. The In-Ga-Zn-O film that can be used for the oxide semiconductor film is nitrogen. 1x10¹⁷/cm³Above 5 × 10¹⁹/cm³The following may be included.

0097In-Ga-Zn-O, which is an oxide of a ternary metal, contains YbFe.₂O₄In GaZnO₄Or Yb₂Fe₃O₇In₂Ga₂ZnO₇Etc., and that strange M. Nakamura, N. Kimizuka, a nd T. Mohri, "The Phase Relations in th e In₂O₃-Ga₂ZnO₄-ZnO System at 1350 degrees ", J. Solid State Chem., 1991, Vol.93, p.298-315 It is described in.

0098In addition, oxide semiconductor films include In-Sn-Ga-Zn-O films, which are oxides of quaternary metals. In-Ga-Zn-O film, In-Sn-Zn-O film, In-A, which are oxides of ternary metals l-Zn-O film, Sn-Ga-Zn-O film, Al-Ga-Zn-O film, Sn-Al-Zn -O film, In-Zn-O film, which is an oxide of binary metal, Sn-Zn-O film, Al-Zn -O film, In-Ga-O film, etc. can be used. The oxide semiconductor film is silicon. May include. Here, for example, the In-Ga-Zn-O film is indium (In), It is an oxide film containing gallium (Ga) and zinc (Zn).

0099Crystals of the oxide semiconductor film grow from the seed crystal layer with anisotropy. As a result, Haitai (B) The semiconductor film having a structure can be configured so that the highly crystalline region is in contact with the insulating surface. It has a heterostructure with a good interface state with less interface state due to unbonded hands. Can provide a semiconductor film to be used.

0100HAADF (high-angle a) of the first crystal structure of the hexagonal system oriented with the c-axis. nnular dark field)-One in three light and dark in the actual observation image of STEM Diffraction images may be observed.

0101HAADF-STEM calculated based on the first crystal structure of the c-axis oriented hexagonal system The actual observation image of is shown in Fig. 6 (A).

0102In addition, the actual observation image of HAADF-STEM of the In-Ga-Zn-O film is shown in Fig. 6 (B).

0103The actual observation images of HAADF-STEM shown in Fig. 6 (A) or Fig. 6 (B) are all three. The first crystal of a c-axis oriented hexagonal system with a single light and darkness and a 9-periodic layer structure. It can be confirmed that it has a structure.

0104The In-Ga-Zn-O film is 300 on a quartz glass substrate using the sputtering method. A film was formed with a thickness of nm. In: Ga: Zn = 1: 1: 1 [atom ratio] as a target The distance between the board and the target is 60 mm, and the power is 0.5 kW using a DC power supply. Then, a film was formed at a pressure of 0.4 Pa. In addition, the substrate temperature during film formation is set to 400 degrees, and spattering is performed. The ang gas was oxygen only, and was flowed through the film forming chamber at a flow rate of 40 sccm.

0105Next, after forming a mask on the oxide semiconductor film 104b having a second crystal structure, the mask is formed. Oxide semiconductor film 104a having a first crystal structure and having a second crystal structure using a screw The oxide semiconductor film 104b is selectively etched to provide an oxide semiconduct having a first crystal structure. A body film 105a and an oxide semiconductor film 105b having a second crystal structure are formed. In addition, the first Oxide semiconductor film 105a having the crystal structure of, Oxide semiconductor film having the second crystal structure 1 05b is collectively referred to as an oxide semiconductor laminate 105. After this, the mask is removed.

0106Oxide semiconductor film 104a having a first crystal structure, oxide semiconductor having a second crystal structure The mask for etching the film 104b is a photolithography process, inkjet. A method, a printing method, or the like can be used as appropriate. Further, an oxide semiconductor film having a first crystal structure 104a, etching of the oxide semiconductor film 104b having a second crystal structure is wet. Thatching or dry etching can be used as appropriate.

0107Next, a pair of electrodes 106 in contact with the oxide semiconductor laminate 105 are formed. Next, the oxide is extinguished Gate insulating film 107 on edge film 102, oxide semiconductor laminate 105, and pair of electrodes 106 To form. Next, the gate electrode 108 is formed on the gate insulating film 107. Also, the gate The insulating film 109 may be formed on the insulating film 107 and the gate electrode 108 (see FIG. 2 (C)). .. ).

0108The pair of electrodes 106 function as a source electrode and a drain electrode.

0109The pair of electrodes 106 are aluminum, chromium, copper, tantalum, titanium, molybdenum, tongue. A metal element selected from gustene, or an alloy containing the above-mentioned metal element as a component, or the above-mentioned It can be formed by using an alloy or the like in which metal elements are combined. Also, manganese, mug Metallic elements selected from one or more of nesium, zirconium, beryllium You may use it. Further, the pair of electrodes 106 may have a single-layer structure or a laminated structure having two or more layers. Good. For example, a single-layer structure of an aluminum film containing silicon, a titanium film on an aluminum film Two-layer structure in which the titanium nitride film is laminated, a two-layer structure in which the titanium film is laminated on the titanium nitride film, on the titanium nitride film Two-layer structure in which a tungsten film is laminated, two layers in which a tungsten film is laminated on a tantalum nitride film Structure, titanium film, aluminum film laminated on the titanium film, and titanium film on it There is a three-layer structure that forms. Also, aluminum, titanium, tantalum, tongueste A film of elements selected from molybdenum, chromium, neodymium, scandium, or multiple sets A combined alloy film or nitride film may be used. One of the materials of the pair of electrodes 106 When copper is used as one, it is in contact with the oxide semiconductor laminate 105 and is made of copper magnesium aluminum. Lamination in which a nium alloy layer is provided and a copper layer is provided in contact with the copper-magnesium-aluminum alloy layer. Should be used.

0110Further, the pair of electrodes 106 are indium tin oxide and indium acid containing tungsten oxide. Indium zinc oxide containing compound, tungsten oxide, indium oxidation containing titanium oxide Add indium tin oxide containing titanium oxide, indium zinc oxide, and silicon oxide. It is also possible to apply a conductive material having translucency such as indium tin oxide. Also, It is also possible to form a laminated structure of the above-mentioned conductive material having translucency and the above-mentioned metal element.

0111The pair of electrodes 106 are formed by a printing method or an inkjet method. Or, spatter After forming a conductive film by a tarling method, a CVD method, a vapor deposition method, etc., a mask is formed on the conductive film. It is formed by etching a conductive film. The mask formed on the conductive film is a printing method, inkjet A method or a photolithography method can be used as appropriate.

0112After forming a conductive film on the oxide semiconductor film 104b having a second crystal structure, multi-gradation An uneven mask is formed by a photomask, and the mask is used to form a first crystal structure. Oxide semiconductor film 104a having a second crystal structure, an oxide semiconductor film 104b having a second crystal structure, After etching the conductive film, the uneven mask is separated by ashing, and the separation is performed. By selectively etching the conductive film with the mask, the oxide semiconductor laminate 105 and And a pair of electrodes 106 can be formed. Depending on the process, the number of photomasks and the number of photomasks The number of lithographic steps can be reduced.

0113The gate insulating film 107 includes a silicon oxide film, a silicon oxide nitride film, a silicon nitride film, and an acid nitride. Silicon chemical film, aluminum oxide film, aluminum nitride film, or gallium oxide film It can be formed in a single layer or in layers. The gate insulating film 107 is an oxide semiconducting material. The portion in contact with the body laminate 105 preferably contains oxygen, and particularly preferably the oxide insulating film. Like 102, it is formed by an oxide insulating film that releases oxygen by heating. Silicon oxide film By using, oxygen can be diffused in the oxide semiconductor laminate 105, and the characteristics are good. Can be.

0114Also, as the gate insulating film 107, hafnium silicate (HfSiO)_x) Membrane, nitrogen added Added hafnium silicate (HfSi)_xO_yN_z) Membrane, hafnium with nitrogen added Aluminate (HfAl)_xO_yN_z) Membrane, hafnium oxide film, yttrium oxide film, etc. Gate leakage can be reduced by using a high-k material film. Furthermore, high-k Material film, silicon oxide film, silicon nitride film, silicon nitride film, silicon nitride film , Aluminum oxide film, aluminum nitride film, and gallium oxide film. It can be a laminated structure with. The thickness of the gate insulating film 107 is 1 nm or more and 300 nm. Hereinafter, it is more preferable that the thickness is 5 nm or more and 50 nm or less.

0115The gate insulating film 107 is formed by a sputtering method, a CVD method, or the like.

0116Before forming the gate insulating film 107, oxygen was applied to the surface of the oxide semiconductor laminate 105. Table of oxide semiconductor laminate 105 exposed to plasma of oxidizing gas such as ozone and nitrous oxide The surface may be oxidized to reduce oxygen defects.

0117The gate electrode 108 includes aluminum, chromium, copper, tantalum, titanium, molybdenum, and tongue. Metal elements selected from Gusten, alloys containing the above-mentioned metal elements as components, and the above-mentioned metal elements It can be formed by using an alloy or the like in which the above are combined. Also, manganese, magnesium , Zirconium, beryllium, or any metal element selected from one or more Good. Further, the gate electrode 108 may have a single-layer structure or a laminated structure having two or more layers. Example For example, a single-layer structure of an aluminum film containing silicon, and a titanium film laminated on the aluminum film. Two-layer structure, two-layer structure in which a titanium film is laminated on a titanium nitride film, tongues on a titanium nitride film Two-layer structure in which a ten film is laminated, a two-layer structure in which a tungsten film is laminated on a tantalum nitride film, A tongue film and an aluminum film are laminated on the titanium film, and a titanium film is further formed on the tongue film. There is a three-layer structure. Also, aluminum, titanium, tantalum, tungsten, and moly A film of elements selected from butene, chromium, neodymium, scandium, or a combination of multiple elements. An alloy film or a nitride film may be used.

0118Further, the gate electrode 108 is an indium acid containing indium tin oxide and tungsten oxide. Indium zinc oxide containing compound, tungsten oxide, indium oxidation containing titanium oxide Add indium tin oxide containing titanium oxide, indium zinc oxide, and silicon oxide. It is also possible to apply a conductive material having translucency such as indium tin oxide. Also, It is also possible to form a laminated structure of the above-mentioned conductive material having translucency and the above-mentioned metal element.

0119Further, as a material layer in contact with the gate insulating film between the gate electrode 108 and the gate insulating film, Nitrogen-containing In-Ga-Zn-O film, nitrogen-containing In-Sn-O film, and nitrogen-containing In -Ga-O film, In-Zn-O film containing nitrogen, Sn-O film containing nitrogen, and nitrogen It is preferable to provide an In-O film or a metal nitride film (InN, ZnN, etc.). These membranes Has a work function of 5 eV, preferably 5.5 eV or higher, and the electrical characteristics of the transistor It is possible to make a positive voltage and realize a so-called normally-off switching element. To. For example, when using an In-Ga-Zn-O film containing nitrogen, at least an oxide semiconductor Uses an In-Ga-Zn-O film with a higher nitrogen concentration than the laminate 105, specifically 7 atomic% or more. There is.

0120The gate electrode 108 is formed by a printing method or an inkjet method. Or, spatter After forming a conductive film by a tarling method, a CVD method, a vapor deposition method, etc., a mask is formed on the conductive film. It is formed by etching a conductive film. The mask formed on the conductive film is a printing method, inkjet A method or a photolithography method can be used as appropriate.

0121The insulating film 109 can be formed by appropriately using the insulating films listed in the gate insulating film 107. To. Further, when a silicon nitride film obtained by a sputtering method is formed as the insulating film 109, , It is possible to prevent the ingress of moisture and alkali metals from the outside, and oxide semiconductor lamination The content of impurities in the body 105 can be reduced.

0122After the gate insulating film 107 or the insulating film 109 is formed, it contains almost all hydrogen and water. No atmosphere (nitrogen atmosphere, oxygen atmosphere, dry air atmosphere (for example, dew point for moisture) Heat treatment (temperature range 150 degrees or more) with -40 degrees or less, preferably dew point -60 degrees or less) 650 degrees or less, preferably 200 degrees or more and 500 degrees or less) may be performed.

0123Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transistor having an oxide semiconductor laminate having a hexagonal crystal structure in the channel Can be made.

0124The oxide semiconductor laminate shown in the present embodiment is formed in a region near the interface with the gate insulating film. A transistor with stable electrical characteristics and high reliability due to its high crystallinity and high uniformity. Obtainable. In addition, it has a hexagonal bond on the ab plane and is c-axis oriented. Oxide semiconductor laminates with crystals and / or hexagonal crystals are used in the channel region of the transistor. When used in the region, before and after light irradiation of the transistor, or bias-heat stress (BT) Even before and after the test, the amount of change in the threshold voltage of the transistor is small, and the electrical characteristics are stable. A transistor having a property can be manufactured.

0125(Embodiment 2) In this embodiment, the structure and manufacturing method of the transistor different from those in the first embodiment are shown in the figure. This will be described with reference to 7 and FIG. In the present embodiment, the oxide insulating film and the oxide semiconductor laminate It is different from the first embodiment in that a pair of electrodes is provided between the two electrodes. In addition, FIG. 7 which is a top view ( The cross-sectional view of the alternate long and short dash CD in A) corresponds to FIG. 7 (B). In FIG. 7 (A), the substrate 10 1. The oxide insulating film 102, the gate insulating film 117, and the insulating film 119 are omitted. Figure 8 Is a cross-sectional view illustrating the manufacturing process of the transistor shown in FIG. 7 (B).

0126The transistor shown in FIG. 7 (B) has an oxide insulating film 102 formed on the substrate 101 and an acid. A pair of electrodes that function as a source electrode and a drain electrode formed on the compound insulating film 102. 116, an oxide insulating film 102, and a pair of electric wires that function as source and drain electrodes. An oxide semiconductor laminate 115 covering the pole 116, an oxide insulating film 102, and a pair of electrodes 116. , And the gate insulating film 117 formed on the oxide semiconductor laminate 115 and the gate insulating film 1 It has a gate electrode 118 that overlaps with the oxide semiconductor laminate 115 via 17. Also, The gate insulating film 117 and the insulating film 119 covering the gate electrode 118 may be provided. Furthermore, Even if the opening of the insulating film 119 has a pair of wires 120 in contact with the pair of electrodes 116 Good.

0127The oxide semiconductor laminate 115 is in contact with the oxide insulating film 102 and the pair of electrodes 116. An oxide semiconductor film 115a having a crystal structure and an oxide semiconductor film 1 having a first crystal structure An oxide semiconductor film 115b having a second crystal structure in contact with 15a is laminated. It is characterized by.

0128Further, the oxide semiconductor film 115b having the second crystal structure is used as a seed crystal, and the first crystal structure is used. The oxide semiconductor film 115a having the above is characterized by crystal growth.

0129Similar to the first embodiment, the oxide semiconductor film having the second crystal structure and the first crystal structure is Since both are trigonal and / or hexagonal, a hexagonal lattice image can be confirmed from the c-axis direction. ..

0130The oxide semiconductor film 115a having a first crystal structure and the oxide having a second crystal structure Each of the semiconductor films 115b is a non-single crystal, and the entire oxide semiconductor film is in an amorphous state ( It has crystals with c-axis orientation instead of (amorphous state).

0131Next, the method of manufacturing the transistor shown in FIG. 7B will be described with reference to FIG.

0132As shown in FIG. 8 (A), the oxide insulating film 102 is formed on the substrate 101 as in the first embodiment. Form. Next, a pair of electrodes 116 are formed on the oxide insulating film 102. Next, a pair of electricity On the pole 116 and the oxide insulating film 102, the first oxide semiconductor film 113a and the second oxide The semiconductor film 113b is formed.

0133The pair of electrodes 116 are made of the same material and manufacturing method as the pair of electrodes 106 shown in the first embodiment. It can be formed by using it as appropriate.

0134The first oxide semiconductor film 113a and the second oxide semiconductor film 113b are shown in the first embodiment. Materials and operations similar to those of the first oxide semiconductor film 103a and the second oxide semiconductor film 103b It can be formed by appropriately using a manufacturing method.

0135Next, the first heat treatment is performed in the same manner as in the first embodiment. By the first heat treatment, the second acid Crystal growth starts from the surface of the compound semiconductor film 113b toward the first oxide semiconductor film 113a. Therefore, the second oxide semiconductor film 113b is different from the oxide semiconductor film 114b having a second crystal structure. Become. Further, the oxide semiconductor film 114b having the second crystal structure has crystals oriented in the c-axis. To do.

0136By subsequently performing the first heat treatment, the oxide semiconductor film 114b having the second crystal structure is formed. As a seed, the crystal growth of the first oxide semiconductor film 113a is an oxide having a second crystal structure. Proceeding from the interface with the semiconductor film 114b toward the oxide insulating film 102, it has a first crystal structure. The oxide semiconductor film 114a is formed. In addition, an oxide semiconductor having a first crystal structure Membrane 114a has crystals oriented in the c-axis. (See Figure 8 (B).).

0137From the above steps, the oxide semiconductor film 114a having the first crystal structure and the second crystal structure are obtained. The oxide semiconductor film 114b can be formed.

0138Next, after forming a mask on the oxide semiconductor film 114b having a second crystal structure, the mask is formed. Oxide semiconductor film 114a having a first crystal structure and having a second crystal structure using a screw The oxide semiconductor film 114b is selectively etched to provide an oxide semiconduct having a first crystal structure. A body film 115a and an oxide semiconductor film 115b having a second crystal structure are formed. In addition, the first Oxide semiconductor film 115a having the crystal structure of, Oxide semiconductor film having the second crystal structure 1 15b is collectively referred to as an oxide semiconductor laminate 115. After this, the mask is removed.

0139Next, the game is placed on the oxide insulating film 102, the pair of electrodes 116, and the oxide semiconductor laminate 115. The insulating film 117 is formed. Next, the gate electrode 118 is formed on the gate insulating film 117. ..

0140After that, the insulating film 119 is formed on the gate insulating film 117 and the gate electrode 118. next, After forming a mask on the insulating film 119, the gate insulating film 117 and a part of the insulating film 119 are partially formed. It is hatched to form an opening. Next, it connects to the pair of electrodes 116 through the opening. Wiring 120 may be formed (see Figure 8 (C)).

0141The gate insulating film 117 is made of the same material and manufacturing method as the gate insulating film 107 shown in the first embodiment. It can be formed using the method as appropriate.

0142The gate electrode 118 has the same material and manufacturing method as the gate electrode 108 shown in the first embodiment. It can be formed by using it as appropriate.

0143The insulating film 119 appropriately uses the same material and manufacturing method as the insulating film 109 shown in the first embodiment. Can be formed.

0144The wiring 120 may be formed by appropriately using the same material and manufacturing method as the pair of electrodes 116. it can.

0145Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transition having an oxide semiconductor laminate with hexagonal crystals in the channel region Can be produced.

0146The oxide semiconductor laminate shown in the present embodiment is formed in a region near the interface with the gate insulating film. A transistor with stable electrical characteristics and high reliability due to its high crystallinity and high uniformity. Obtainable. In addition, it has a hexagonal bond on the ab plane and is c-axis oriented. Oxide semiconductor laminates with crystals and / or hexagonal crystals are used in the channel region of the transistor. By using it in the region, light irradiation to the transistor, or bias-heat stress (BT) test Even before and after, the amount of change in the threshold voltage of the transistor is small, and stable electrical characteristics are achieved. A transistor having a transistor can be manufactured.

0147In addition, this embodiment can be appropriately combined with other embodiments.

0148(Embodiment 3) In the present embodiment, a transistor using an oxide semiconductor film as a channel and a method for manufacturing the same are used. This will be described with reference to FIGS. 9 and 10. FIG. 9B shows a form of the configuration of the semiconductor device. It is a cross-sectional view for explaining the structure of a certain transistor, and the one-dot dashed line A in FIG. -Corresponds to the cross-sectional view of B. In addition, in FIG. 9A, the substrate 101 and the oxide insulating film 102 , Gate insulating film 107, and insulating film 109 are omitted. FIG. 10 is shown in FIG. 9 (B). It is sectional drawing explaining the manufacturing process of a transistor.

0149The transistor shown in FIG. 9B is an oxide insulating film 102 formed on the substrate 101 and an acid. The oxide semiconductor laminate 105 formed on the compound insulating film 102 and the oxide semiconductor laminate 10 A pair of electrodes 106 that function as source and drain electrodes formed on 5 and oxidation A game formed on the material insulating film 102, the oxide semiconductor laminate 105, and the pair of electrodes 106. G. Overlapping with the oxide semiconductor laminate 105 via the insulating film 107 and the gate insulating film 107. It has an electrode 108. Insulation that covers the gate insulating film 107 and the gate electrode 108. It may have a membrane 109.

0150The oxide semiconductor laminate 105 is oxidized having a first crystal structure in contact with the oxide insulating film 102. A second object in contact with the semiconductor film 105a and the oxide semiconductor film 105a having the first crystal structure. An oxide semiconductor film 105b having a crystal structure and an oxide semiconductor film 1 having a second crystal structure Oxide semiconductor film 105c having a third crystal structure in contact with 05b and the gate insulating film 107 It is characterized in that and is laminated.

0151That is, it has a first crystal structure above and below the oxide semiconductor film 105b having a second crystal structure. It has an oxide semiconductor film 105a and an oxide semiconductor film 105c having a third crystal structure.

0152Further, the oxide semiconductor film 105b having the second crystal structure is used as a seed crystal, and the first crystal structure is used. The oxide semiconductor film 105a having a third crystal structure and the oxide semiconductor film 105c having a third crystal structure Each is characterized by crystal growth.

0153Oxide semiconductor film 105a having a first crystal structure, oxide semiconductor having a third crystal structure The crystal structure of the film 105c is trigonal and / or hexagonal, and YbFe₂O₄Type structure, Yb₂Fe₃O₇It is either a type structure or a non-wurtzite type structure. Non-wurtzite type structure Is a trigonal and / or hexagonal non-wurtzite crystal structure.

0154The crystal structure of the oxide semiconductor film 105b having the second crystal structure is a trigonal crystal and / or It has a wurtzite structure, which is one of the hexagonal crystals.

0155That is, an oxide semiconductor film having a first crystal structure or an oxide semiconductor having a third crystal structure. Since both films are trigonal and / or hexagonal, a hexagonal lattice image can be confirmed from the c-axis direction. it can.

0156The oxide semiconductor film 105a having the first crystal structure and the oxide having the second crystal structure The semiconductor film 105b and the oxide semiconductor film 105c having a third crystal structure are non-single-bonded, respectively. It is a crystal and the entire oxide semiconductor film is not in an amorphous state (amorphous state), but has a c-axis arrangement. It has a facing crystal region. That is, it has an amorphous region and a crystal region oriented in the c-axis.

0157Next, the method of manufacturing the transistor shown in FIG. 9B will be described with reference to FIG.

0158As shown in FIG. 10A, the oxide insulating film 102 is formed on the substrate 101 as in the first embodiment. After forming the first oxide semiconductor film 103a on the oxide insulating film 102, the first oxide semiconductor film 103a is formed. A second oxide semiconductor film 103b is formed on the oxide semiconductor film 103a.

0159The oxide insulating film 102 is formed by using an oxide insulating film that releases a part of oxygen by heating. .. As an oxide insulating film that releases a part of oxygen by heating, it is better than oxygen that satisfies the stoichiometric ratio. It is preferable to use an oxide insulating film containing a large amount of oxygen. Part of oxygen is released by heating The oxide insulating film to be formed is the first oxide semiconductor film 103a and the second oxide semiconductor by heating. Oxygen can be diffused into the membrane 103b. The oxide insulating film 102 is typically oxidized. Silicon, Silicon Nitride, Silicon Nitride, Aluminum Oxide, Aluminium Oxide It can be formed of um, gallium oxide, hafnium oxide, yttrium oxide, or the like.

0160The oxide insulating film 102 is 50 nm or more, preferably 200 nm or more and 500 nm or less. .. By thickening the oxide insulating film 102, the amount of oxygen released from the oxide insulating film 102 is increased. At the interface with the oxide insulating film 102 and the oxide semiconductor film formed later. It is possible to reduce defects in the area.

0161The oxide insulating film 102 is formed by a sputtering method, a CVD method, or the like. By heating The oxide insulating film that releases a part of oxygen is easy to form by using the sputtering method. Therefore, it is preferable.

0162When forming an oxide insulating film in which a part of oxygen is released by heating by the sputtering method , The amount of oxygen in the film-forming gas is preferably high, and oxygen, or a mixed gas of oxygen and a rare gas, etc. Can be used. Typically, the oxygen concentration in the film-forming gas is 6% or more and 100% or less. Is preferable.

0163The first oxide semiconductor film 103a is trigonal and / or hexagonal and non-tetragonal by heating. Wurtzite type, YbFe₂O₄Type structure, Yb₂Fe₃O₇Mold structure and its modified structure It is formed using an oxide semiconductor film that can have one of the crystal structures.

0164As an example of an oxide semiconductor film having a first crystal structure, In-G, which is an oxide of a ternary metal. The a-Zn-O membrane has trigonal and / or hexagonal non-wurtzite crystals. Also, three yuan YbFe is used for the In-Ga-Zn-O film, which is an oxide of the based metal.₂O₄InG which is a type structure aZnO₄Or Yb₂Fe₃O₇In₂Ga₂ZnO₇Etc., and its deformation Can take a mold structure (M. Nakamura, N. Kimizuka, and T. Mohri, "The Phase Relations in the In₂O₃-Ga₂ZnO₄-ZnO System at 1350 degrees ", J. Soli d State Chem., 1991, Vol.93, p.298-315).

0165The first oxide semiconductor film 103a is In-Sn-Ga-, which is an oxide of a quaternary metal. Zn-O film, In-Ga-Zn-O film, which is an oxide of ternary metal, In-Sn-Zn- O film, In-Al-Zn-O film, Sn-Ga-Zn-O film, Al-Ga-Zn-O film, S n-Al-Zn-O film, In-Zn-O film, which is an oxide of binary metal, Sn-Zn-O A film, an Al-Zn-O film, an In-Ga-O film, or the like can be used. In addition, the above oxide SiO for semiconductors₂May include. Here, for example, the In-Ga-Zn-O film is an in-Ga-Zn-O film. It is an oxide film having gallium (In), gallium (Ga), and zinc (Zn). In addition, the first As the oxide semiconductor film 103a of the above metal oxide, 1 × 10¹⁷/cm³Above 5 × 10¹⁹/cm³It may contain less than nitrogen.

0166The metal oxide that can be formed on the first oxide semiconductor film 103a is energy. The gap is 2 eV or more, preferably 2.5 eV or more, more preferably 3 eV or more. In this way, by using an oxide semiconductor with a wide energy gap, the transistor can be used. The current can be reduced.

0167The second oxide semiconductor film 103b is an oxide that can become a wurtzite-type crystal structure by heating. It is formed using a semiconductor film. The oxide semiconductor film that can have a wurtzite-type crystal structure is a trigonal crystal. And / or crystals by heat treatment compared to oxide semiconductor films that can have a hexagonal crystal structure It is easy to change and has high crystallinity.

0168As the second oxide semiconductor film 103b, zinc oxide, an oxynitride semiconductor, or the like can be used. Wear. The oxynitride semiconductor is a metal oxide listed in the first oxide semiconductor film 103a, 5 × Ten¹⁹/cm³Above, preferably 1 × 10²⁰/cm³Add more than 7 atomic% nitrogen Can be formed.

0169The second oxide semiconductor film 103b is formed from the first oxide semiconductor film 103a and later. Crystal growth is performed because the third oxide semiconductor film 103c is used as a seed for crystal growth. The thickness may be as high as possible, typically 1 atomic layer or more and 10 nm or less, preferably 2 nm or more and 5n. It may be m or less. Film formation treatment and heating by reducing the thickness of the second oxide semiconductor film 103b Throughput in processing can be increased.

0170The first oxide semiconductor film 103a and the second oxide semiconductor film 103b are sputtered, respectively. It can be formed by a ring method, a coating method, a printing method, a pulse laser vapor deposition method, or the like. spa The first oxide semiconductor film 103a and the second oxide semiconductor film 103b are formed by the tattering method. When forming a film, use either an AC sputtering device, a DC sputtering device, or an RF sputtering device. Use one of the sputtering equipment.

0171The second oxide semiconductor film 103b is formed of an oxynitride semiconductor by a sputtering method. In this case, after forming the first oxide semiconductor film 103a, it is introduced into the sputtering apparatus. An oxynitride semiconductor can be formed by switching the type of nitrogen, that is, by introducing nitrogen. .. That is, the first oxide semiconductor film 103a and the second oxide semiconductor film 103b are continuously formed. It can be produced and has excellent mass productivity.

0172Next, the first heat treatment is performed in the same manner as in the first embodiment.

0173By the first heat treatment, the surface of the second oxide semiconductor film 103b to the first oxide semiconductor film Crystal growth begins toward 103a. The second oxide semiconductor film 103b is easily crystallized. Therefore, the second oxide semiconductor film 103b is entirely crystallized and has a wurtzite-type crystal structure. The oxide semiconductor film 104b having the crystal structure of 2 is obtained. In addition, the second oxide semiconductor film 10 Crystal growth from the surface of 3b toward the first oxide semiconductor film 103a was c-axis oriented. It becomes a crystal region. That is, the oxide semiconductor film 104b having the second crystal structure is on the ab plane. It has a hexagonal connection on the plane. In addition, the film thickness of the layer having hexagonal bonds They are laminated and connected in the direction (c-axis direction) and are c-axis oriented.

0174By continuing the first heat treatment, the oxide semiconductor film 104b having the second crystal structure is seeded. As a result, the crystal growth of the first oxide semiconductor film 103a is an oxide half having a second crystal structure. It proceeds from the interface with the conductor film 104b toward the oxide insulating film 102. Has a second crystal structure Since the oxide semiconductor film 104b is c-axis oriented, it is oxidized having the second crystal structure. By using the material semiconductor film 104b as a seed, the oxide semiconductor film 104b having a second crystal structure The first oxide semiconductor film 103a can be crystal-grown so as to be substantially the same as the crystal axis of. it can. That is, the first oxide semiconductor film 103a is crystal-grown while being c-axis oriented. Is possible. That is, the oxide semiconductor film 104a having the first crystal structure is on the ab plane. It has a hexagonal connection on the plane of the eggplant. In addition, the layer with hexagonal bonds has a film thickness. It is laminated and connected in the direction (c-axis direction), and is c-axis oriented. By the above process, c-axis An oxide semiconductor film 104a having an oriented first crystal structure can be formed (Fig. 1). See 0 (B). ).

0175By the first heat treatment, crystals are formed in the direction perpendicular to the surface of the second oxide semiconductor film 103b. When grown, it has an oxide semiconductor film 104a having a first crystal structure and a second crystal structure. The c-axis of the oxide semiconductor film 104b is substantially vertical to the surface.

0176Further, by the first heat treatment, the first oxide semiconductor film 103a and the second oxide semiconducting material are obtained. As the hydrogen contained in the body membrane 103b is released (that is, dehydrogenated and dehydrated), the acid Part of the oxygen contained in the compound insulating film 102 is the first oxide semiconductor film 103a and the second acid. Of the compound semiconductor film 103b and the first oxide semiconductor film 103a in the oxide insulating film 102 Diffuses near the interface. By this step, the first oxide semiconductor film 103a and the second oxidation Oxygen defects contained in the semiconductor film 103b can be reduced, and the oxide insulating film can be reduced. Oxide by diffusing oxygen in the vicinity of the first oxide semiconductor film 103a in 102 By reducing defects at the interface between the insulating film 102 and the first oxide semiconductor film 103a. Wear. As a result, the oxide semiconduct with the first crystal structure with reduced hydrogen concentration and oxygen defects It is possible to form a body film 104a and an oxide semiconductor film 104b having a second crystal structure. To.

0177Next, as shown in FIG. 10 (C), on the oxide semiconductor film 104b having the second crystal structure. A third oxide semiconductor film 103c is formed. The third oxide semiconductor film 103c is a first acid. It can be formed by using the same material and manufacturing method as the compound semiconductor film 103a. Third The thickness of the oxide semiconductor film 103c is determined by the practitioner depending on the device to be manufactured. Just do it. For example, the first oxide semiconductor film 103a, the second oxide semiconductor film 103b, and the like. The total thickness of the third oxide semiconductor film 103c shall be 10 nm or more and 200 nm or less.

0178The first oxide semiconductor film 103a to the third oxide semiconductor film by the sputtering method. Leakage rate in the processing chamber of the sputtering equipment when depositing any one or more of 103c 1x10^-10Pa m³By setting it to / sec or less, during film formation by the sputtering method Arca in the first oxide semiconductor film 103a to the third oxide semiconductor film 103c It is possible to reduce the mixing of impurities such as metal and hydrogen. In addition, the suction type true as an exhaust system By using an empty pump (for example, a cryopump), alkali metal and hydrogen can be used from the exhaust system. It is possible to reduce the backflow of impurities such as.

0179In addition, any one or more of the first oxide semiconductor film 103a to the third oxide semiconductor film 103c. Gas introduced into the processing chamber of the sputtering equipment when forming the film, such as nitrogen gas or acid A raw gas, an argon gas, or the like may be introduced in a heated state to form a film. As a result , One or more of the first oxide semiconductor film 103a to the third oxide semiconductor film 103c The hydrogen content contained can be reduced.

0180Further, by the sputtering method, the first oxide semiconductor film 103a to the third oxide semiconductor film Before depositing any one or more of 103c, the sputtering device, the surface of the target, or May be preheated to remove water or hydrogen contained therein. This As a result, any one of the first oxide semiconductor film 103a to the third oxide semiconductor film 103c The hydrogen content contained in the above can be reduced.

0181Next, a second heat treatment is performed. The temperature of the second heat treatment is 150 degrees or more and 650 degrees or less, which is good. Furthermore, it should be 200 degrees or more and 500 degrees or less. In addition, the heating time of the second heat treatment is 1 minute or more. 24 hours or less.

0182In the second heat treatment, the atmosphere can be the same as that of the first heat treatment. Further, as the heating device, the same heating device as in the first heat treatment can be appropriately used.

0183By performing the second heat treatment, an acid having a second crystal structure having a wurtzite type crystal structure Crystal growth begins from the compound semiconductor film 104b toward the third oxide semiconductor film 103c. No. Since the oxide semiconductor film 104b having the crystal structure of 2 is c-axis oriented, it has a second crystal structure. By using the oxide semiconductor film 104b having a structure as a seed, the third oxide semiconductor film 103c can be obtained. , Oxide semiconductor film 10 having a second crystal structure, similar to the first oxide semiconductor film 103a. The third oxide semiconductor film 103c is crystal-grown so as to be substantially the same as the crystal axis of 4b. Can be done. That is, the third oxide semiconductor film 103c is crystal-grown while being c-axis oriented. It is possible. That is, the oxide semiconductor film 104c having the third crystal structure has an ab plane. It has a hexagonal connection in the plane of. In addition, the layer with hexagonal bonds is a film. They are laminated and connected in the thick direction (c-axis direction) and are c-axis oriented. By the above process An oxide semiconductor film 104c having a c-axis oriented third crystal structure can be formed. Further, since the crystal grows using the oxide semiconductor film 104b having the second crystal structure as a seed, the second crystal grows. Crystal growth of the oxide semiconductor film 103c of 3 is promoted, and an oxide semiconduct having a third crystal structure The surface of the body membrane 104c has high crystallinity and high uniformity (see FIG. 10 (D)).

0184By the second heat treatment, is it the surface of the oxide semiconductor film 104b having the second crystal structure? When the crystal grows in the vertical direction, the c-axis of the oxide semiconductor film 104c having the third crystal structure becomes The surface of the oxide semiconductor film 104b having the second crystal structure is substantially vertical.

0185Further, by the second heat treatment, the third oxide semiconductor film 10 is obtained in the same manner as in the first heat treatment. The hydrogen contained in 3c is released (that is, dehydrogenated and dehydrated). As a result, hydrogen concentration It is possible to form an oxide semiconductor film 104c having a third crystal structure with a reduced degree. ..

0186From the above steps, an oxide half having a first crystal structure having a trigonal and / or hexagonal structure. Conductor film 104a, oxide semiconductor film 104b having a second crystal structure, and a third crystal structure The oxide semiconductor film 104c having the above can be formed. Oxidation with a first crystal structure Material semiconductor film 104a, oxide semiconductor film 104b having a second crystal structure, and a third crystal It is possible to reduce the hydrogen concentration and oxygen defects contained in the oxide semiconductor film 104c having a structure. it can. When hydrogen is contained in an oxide semiconductor, a part of it becomes a donor and becomes a carrier. A certain electron is generated. Oxygen defects in oxide semiconductors also serve as donors. An electron that is a carrier is generated. Therefore, an oxide semiconductor film having a first crystal structure It has 104a, an oxide semiconductor film 104b having a second crystal structure, and a third crystal structure. By reducing the hydrogen concentration and oxygen defects in the oxide semiconductor film 104c, the catalyst in the oxide semiconductor can be reduced. The rear concentration can be reduced, and the threshold voltage minor of the transistor to be manufactured later The shift can be reduced. For these reasons, an oxide semiconductor having a first crystal structure It has a film 104a, an oxide semiconductor film 104b having a second crystal structure, and a third crystal structure. It is produced later by reducing the hydrogen concentration and the amount of oxygen defects in the oxide semiconductor film 104c. It is possible to reduce the negative shift of the threshold voltage of the transistor.

0187Next, as in the first embodiment, a mass is placed on the oxide semiconductor film 104c having a third crystal structure. After forming the oxide semiconductor film 104a, which has a first crystal structure using the mask, An oxide semiconductor film 104b having a second crystal structure and an oxide half having a third crystal structure. Oxide semiconductor film 10 having a first crystal structure by selectively etching the conductor film 104c 5a, an oxide semiconductor film 105b having a second crystal structure, and an acid having a third crystal structure A compound semiconductor film 105c is formed. The oxide semiconductor film 105 having the first crystal structure a, an oxide semiconductor film 105b having a second crystal structure, and oxidation having a third crystal structure The material semiconductor film 105c is collectively referred to as an oxide semiconductor laminate 105. After this, remove the mask Leave.

0188Next, a pair of electrodes 106 in contact with the oxide semiconductor laminate 105 are formed. Next, the oxide is extinguished Gate insulating film 107 on edge film 102, oxide semiconductor laminate 105, and pair of electrodes 106 To form. Next, the gate electrode 108 is formed on the gate insulating film 107. Also, the gate The insulating film 109 may be formed on the insulating film 107 and the gate electrode 108 (see FIG. 10 (E)). Teru. ).

0189The pair of electrodes 106 are made of the same material and manufacturing method as the pair of electrodes 106 shown in the first embodiment. It can be formed by using it as appropriate.

0190After forming a conductive film on the oxide semiconductor film 104c having a third crystal structure, multi-gradation An uneven mask is formed by a photomask, and the mask is used to form a first crystal structure. Oxide semiconductor film 104a having a second crystal structure, and oxide semiconductor film 104b having a second crystal structure. After etching the oxide semiconductor film 104c having a third crystal structure and the conductive film, The uneven mask is separated by ashing, and the conductive film is selectively selected by the separated mask. To form the oxide semiconductor laminate 105 and the pair of electrodes 106 by etching the oxide semiconductor. Can be done. This process reduces the number of photomasks and the number of photolithography processes. be able to.

0191The gate insulating film 107 is made of the same material and manufacturing method as the gate insulating film 107 shown in the first embodiment. It can be formed using the method as appropriate.

0192Before forming the gate insulating film 107, oxygen was applied to the surface of the oxide semiconductor laminate 105. Table of oxide semiconductor laminate 105 exposed to plasma of oxidizing gas such as ozone and nitrous oxide The surface may be oxidized to reduce oxygen defects.

0193The gate electrode 108 uses the same material and manufacturing method as the gate electrode 108 shown in the first embodiment. It can be formed by using it as appropriate.

0194After the gate insulating film 107 or the insulating film 109 is formed, it contains almost all hydrogen and water. No atmosphere (nitrogen atmosphere, oxygen atmosphere, dry air atmosphere (for example, dew point for moisture) Heat treatment (temperature range 150 degrees or more) with -40 degrees or less, preferably dew point -60 degrees or less) 650 degrees or less, preferably 200 degrees or more and 500 degrees or less) may be performed.

0195Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transition having an oxide semiconductor laminate having a hexagonal crystal region in the channel Can be produced.

0196The oxide semiconductor laminate shown in the present embodiment is formed in a region near the interface with the gate insulating film. A transistor with stable electrical characteristics and high reliability due to its high crystallinity and high uniformity. Obtainable. In addition, it has a hexagonal bond on the ab plane and is c-axis oriented. An oxide semiconductor laminate having a crystal region of a crystal and / or a hexagonal structure is used as a transistor channel. By using it in the region, before and after light irradiation of the transistor, or bias-heat stress (B) T) Stable electricity with little change in transistor threshold voltage before and after the test A transistor having specific characteristics can be manufactured.

0197The oxynitride semiconductor has a smaller energy gap than the oxide semiconductor and is a carrier. Easy to shed. Therefore, in the transistor, an oxide semiconductor film having a third crystal structure By reducing the film thickness of 105c, the oxide semiconductor film 105b having a second crystal structure can be obtained. It is an embedded channel transistor that serves as a channel. As a result, the gate insulating film 107 and And is not affected by the interface of the oxide semiconductor film 105c having a third crystal structure, and has good electrical characteristics. A transistor having a property can be manufactured.

0198(Embodiment 4) In the present embodiment, the structure and manufacturing method of the transistor different from those in the third embodiment are shown in the figure. This will be described with reference to 11 and FIG. In the present embodiment, the oxide insulating film and the oxide semiconductor product It differs from the third embodiment in that a pair of electrodes is provided between the layers. It should be noted that it is a top view. The cross-sectional view of the alternate long and short dash CD in 11 (A) corresponds to FIG. 11 (B). In Fig. 11 (A) , Substrate 101, oxide insulating film 102, gate insulating film 117, and insulating film 119 are omitted. There is. FIG. 12 is a cross-sectional view illustrating the manufacturing process of the transistor shown in FIG. 11 (B).

0199The transistor shown in FIG. 11B includes an oxide insulating film 102 formed on the substrate 101 and A pair of electricity that functions as a source electrode and a drain electrode formed on the oxide insulating film 102. A pole 116, an oxide insulating film 102, and a pair of functions as a source electrode and a drain electrode. An oxide semiconductor laminate 115 covering the electrodes 116, an oxide insulating film 102, and a pair of electrodes 11 6 and the gate insulating film 117 formed on the oxide semiconductor laminate 115 and the gate insulating film It has a gate electrode 118 that overlaps with the oxide semiconductor laminate 115 via 117. Also , The gate insulating film 117 and the insulating film 119 covering the gate electrode 118 may be provided. Furthermore , With a pair of wires 120 in contact with the pair of electrodes 116 at the opening of the insulating film 119. May be good.

0200The oxide semiconductor laminate 115 is in contact with the oxide insulating film 102 and the pair of electrodes 116. An oxide semiconductor film 115a having a crystal structure and an oxide semiconductor film 1 having a first crystal structure It has an oxide semiconductor film 115b having a second crystal structure in contact with 15a and a second crystal structure. Acid having a third crystal structure in contact with the oxide semiconductor film 115b and the gate insulating film 117 It is characterized in that the compound semiconductor film 115c is laminated.

0201That is, it has a first crystal structure above and below the oxide semiconductor film 115b having a second crystal structure. It has an oxide semiconductor film 115a and an oxide semiconductor film 115c having a third crystal structure.

0202Further, the oxide semiconductor film 115b having the second crystal structure is used as a seed crystal, and the first crystal structure is used. The oxide semiconductor film 115a having a third crystal structure and the oxide semiconductor film 115c having a third crystal structure Each is characterized by crystal growth.

0203Oxide semiconductor film 115a having a first crystal structure, oxide semiconductor having a third crystal structure The crystal structure of the membrane 115c is trigonal and / or hexagonal and non-wurtzite, YbFe.₂O₄Type structure, Yb₂Fe₃O₇It is either a mold structure or a modified structure thereof. In addition, it should be noted. The non-wurtzite type structure is a trigonal and / or hexagonal non-wurtzite type crystal structure.

0204The crystal structure of the oxide semiconductor film 115b having the second crystal structure is a trigonal crystal and / or It is a wurtzite type structure that is one of the hexagonal crystals.

0205Similar to the third embodiment, the oxide semiconductor film 115a to the third crystal having the first crystal structure Since the oxide semiconductor film 115c having a structure is both trigonal and / or hexagonal, the c-axis A hexagonal grid image can be confirmed from the direction.

0206The oxide semiconductor film 115a having a first crystal structure and the oxide having a second crystal structure The semiconductor film 115b and the oxide semiconductor film 115c having a third crystal structure are non-single-bonded, respectively. It is a crystal and the entire oxide semiconductor film is not in an amorphous state (amorphous state), but has a c-axis arrangement. It has a facing crystal region. That is, it has an amorphous region and a crystal region oriented in the c-axis.

0207Next, the method of manufacturing the transistor shown in FIG. 11B will be described with reference to FIG.

0208As shown in FIG. 12A, the oxide insulating film 102 is formed on the substrate 101 as in the first embodiment. To form. Next, a pair of electrodes 116 are formed on the oxide insulating film 102. Then a pair On the electrode 116 and the oxide insulating film 102, the first oxide semiconductor film 113a and the second oxidation A semiconductor film 113b is formed.

0209The pair of electrodes 116 are made of the same material and manufacturing method as the pair of electrodes 106 shown in the first embodiment. It can be formed by using it as appropriate.

0210The first oxide semiconductor film 113a and the second oxide semiconductor film 113b are shown in the first embodiment. Materials and operations similar to those of the first oxide semiconductor film 103a and the second oxide semiconductor film 103b It can be formed by appropriately using a manufacturing method.

0211Next, the first heat treatment is performed in the same manner as in the first embodiment. By the first heat treatment, the second acid Crystal growth starts from the surface of the compound semiconductor film 113b toward the first oxide semiconductor film 113a. Therefore, the second oxide semiconductor film 113b has a second crystal structure having a wurtzite type crystal structure. It becomes the oxide semiconductor film 114b to have. Further, an oxide semiconductor film having a second crystal structure 1 14b has crystals oriented in the c-axis.

0212By subsequently performing the first heat treatment, the oxide semiconductor film 114b having the second crystal structure is formed. As a seed, the crystal growth of the first oxide semiconductor film 113a is an oxide having a second crystal structure. Proceeding from the interface with the semiconductor film 114b toward the oxide insulating film 102, it has a first crystal structure. The oxide semiconductor film 114a is formed. In addition, an oxide semiconductor having a first crystal structure Membrane 114a has a c-axis oriented crystal region.

0213Next, the third oxide semiconductor film 113 is placed on the oxide semiconductor film 114b having the second crystal structure. The third oxide semiconductor film 113c, which forms c (see FIG. 12 (B)), is in the third embodiment. It shall be formed by appropriately using the same material and manufacturing method as the third oxide semiconductor film 103c shown. Can be done.

0214Next, the second heat treatment is performed in the same manner as in the third embodiment. By performing the second heat treatment, c Is it the interface with the oxide semiconductor film 114b having a second crystal structure having a Ruth ore type crystal structure? Crystal growth begins toward the third oxide semiconductor film 113c, and the third oxide semiconductor film 11 3c is an oxide semiconductor film 114c having a third crystal structure. Also, the third crystal structure The oxide semiconductor film 114c having the above has a crystal region oriented with a c-axis. (See Fig. 12 (C) Teru. ).

0215From the above steps, an oxide half having a first crystal structure having a trigonal and / or hexagonal structure. Conductor film 114a, oxide semiconductor film 114b having a second crystal structure, and a third crystal structure The oxide semiconductor film 114c having the above can be formed.

0216Next, after forming a mask on the oxide semiconductor film 114c having a third crystal structure, the mask is formed. Oxide semiconductor film 114a having a first crystal structure and having a second crystal structure using a screw Selective oxide semiconductor film 114b and oxide semiconductor film 114c having a third crystal structure The oxide semiconductor film 115a having the first crystal structure and the second crystal structure are etched into. The oxide semiconductor film 115b having the oxide semiconductor film 115b and the oxide semiconductor film 115c having the third crystal structure Form. The oxide semiconductor film 115a having the first crystal structure and the second crystal structure are provided. The oxide semiconductor film 115b and the oxide semiconductor film 115c having a third crystal structure are included. It is referred to as an oxide semiconductor laminate 115. After this, the mask is removed.

0217Next, the game is placed on the oxide insulating film 102, the pair of electrodes 116, and the oxide semiconductor laminate 115. The insulating film 117 is formed. Next, the gate electrode 118 is formed on the gate insulating film 117. ..

0218After that, the insulating film 119 is formed on the gate insulating film 117 and the gate electrode 118. next, After forming a mask on the insulating film 119, the gate insulating film 117 and a part of the insulating film 119 are partially formed. It is hatched to form an opening. Next, it connects to the pair of electrodes 116 through the opening. Wiring 120 may be formed (see Figure 12 (D)).

0219The gate insulating film 117 is made of the same material and manufacturing method as the gate insulating film 107 shown in the first embodiment. It can be formed using the method as appropriate.

0220The gate electrode 118 has the same material and manufacturing method as the gate electrode 108 shown in the first embodiment. It can be formed by using it as appropriate.

0221The insulating film 119 appropriately uses the same material and manufacturing method as the insulating film 109 shown in the first embodiment. Can be formed.

0222The wiring 120 may be formed by appropriately using the same material and manufacturing method as the pair of electrodes 116. it can.

0223Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transistor having an oxide semiconductor laminate having a hexagonal crystal region in the channel region Gista can be made.

0224The oxide semiconductor laminate shown in the present embodiment is formed in a region near the interface with the gate insulating film. A transistor with stable electrical characteristics and high reliability due to its high crystallinity and high uniformity. Obtainable. In addition, it has a hexagonal bond on the ab plane and is c-axis oriented. An oxide semiconductor laminate having a crystal region of a crystal and / or a hexagonal structure is used as a transistor channel. By using it in the region, before and after light irradiation of the transistor, or bias-heat stress (B) T) Stable electricity with little change in transistor threshold voltage before and after the test A transistor having specific characteristics can be manufactured.

0225In addition, this embodiment can be appropriately combined with other embodiments.

0226(Embodiment 5) In the present embodiment, a transistor structure and fabrication different from those of the first to fourth embodiments The method will be described with reference to FIGS. 13 and 14. In the present embodiment, the oxide insulating film and The point that the gate electrode is provided between the gate insulating film is different from the first to fourth embodiments. Become. That is, in the first to fourth embodiments, a top gate type transistor is used. However, in the present embodiment, a bottom gate type transistor will be described. It should be noted that The cross-sectional view of the alternate long and short dash EF in FIG. 13 (A), which is a top view, corresponds to FIG. 13 (B). Figure 1 In 3 (A), the substrate 101, the oxide insulating film 102, the gate insulating film 127, and the insulating film 129 is omitted. FIG. 14 illustrates the manufacturing process of the transistor shown in FIG. 13 (B). It is a cross-sectional view.

0227The transistor shown in FIG. 13 (B) has an oxide insulating film 102 formed on the substrate 101 and The gate electrode 128 formed on the oxide insulating film 102, and the oxide insulating film 102 and the gate. A gate insulating film 127 covering the electrode 128 and a gate electrode 128 via the gate insulating film 127. When superimposed on, the oxide semiconductor laminate 125 and the source electricity in contact with the oxide semiconductor laminate 125 It has a pair of electrodes 126 that function as pole and drain electrodes. Also, the gate insulating film 1 27, an insulating film 129 covering the oxide semiconductor laminate 125 and the pair of electrodes 126 may be provided. I.

0228The oxide semiconductor laminate 125 is oxidized having a first crystal structure in contact with the gate insulating film 127. A second object in contact with the semiconductor film 125b and the oxide semiconductor film 125b having the first crystal structure. It is characterized in that an oxide semiconductor film 125c having a crystal structure is laminated.

0229Further, the oxide semiconductor film 125b having the first crystal structure is used as a seed crystal, and the second crystal structure is used. The oxide semiconductor film 125c having the above is characterized by crystal growth.

0230The oxide semiconductor film 125b having the first crystal structure is one of a trigonal crystal and / or a hexagonal crystal. It has a wurtzite type crystal structure.

0231The oxide semiconductor film 125c having the second crystal structure is a trigonal crystal and / or a hexagonal crystal, and Y bFe₂O₄Type structure, Yb₂Fe₃O₇Crystals of either type structure or non-wurtzite type structure Has a structure.

0232The oxide semiconductor film having the first crystal structure and the oxide semiconductor film having the second crystal structure are Since both are trigonal and / or hexagonal, a hexagonal lattice image can be confirmed from the c-axis direction. ..

0233Oxide semiconductor film 125b having a first crystal structure, oxide semiconductor having a second crystal structure Each of the films 125c is a non-single crystal, and the entire oxide semiconductor film is in an amorphous state (Amol). It has a c-axis oriented crystal region rather than a fuss state). That is, the amorphous region and the c-axis orientation It has a crystalline region.

0234Here, the oxide semiconductor laminate 125 is used as an oxide semiconductor film having a first crystal structure. It has a two-layer structure consisting of 125b and an oxide semiconductor film 125c having a second crystal structure. As shown in the third and fourth embodiments of the application, an oxide semiconductor laminate having a three-layer structure may be used. ..

0235Next, the method of manufacturing the transistor shown in FIG. 13 (B) will be described with reference to FIG.

0236As shown in FIG. 14 (A), the oxide insulating film 102 is formed on the substrate 101 as in the first embodiment. To form. Next, the gate electrode 128 is formed on the oxide insulating film 102. Next, the oxide is extinguished A gate insulating film 127 is formed on the edge film 102 and the gate electrode 128. Next, the gate is cut off A first oxide semiconductor film 123b is formed on the edge film 127.

0237The gate electrode 128 and the gate insulating film 127 are the gate electrodes 1 shown in the first embodiment, respectively. It can be formed by appropriately using the same materials and manufacturing methods as 08 and the gate insulating film 107. To.

0238The first oxide semiconductor film 123b is the same as the second oxide semiconductor film 103b shown in the first embodiment. It can be formed by appropriately using the same material and production method.

0239Next, the first heat treatment is performed in the same manner as in the first embodiment. By the first heat treatment, the first acid Crystal growth begins from the surface of the compound semiconductor film 123b toward the gate insulating film 127, and the first The oxide semiconductor film 124b has a crystal structure. Also, an oxide having a first crystal structure The semiconductor film 124b has a crystal region oriented with a c-axis.

0240Next, the second oxide semiconductor film 123 is placed on the oxide semiconductor film 124b having the first crystal structure. Form c (see Figure 14 (B)). The second oxide semiconductor film 123c is the third embodiment. It is formed by appropriately using the same material and manufacturing method as the third oxide semiconductor film 103c shown in 1. Can be done.

0241Next, the second heat treatment is performed in the same manner as in the third embodiment. By the heat treatment, the first crystal From the interface with the oxide semiconductor film 124b having a structure toward the second oxide semiconductor film 123c Crystal growth begins, and the second oxide semiconductor film 123c is an oxide having a second crystal structure. It becomes a semiconductor film 124c. Further, the oxide semiconductor film 124c having the second crystal structure is c. It has an axially oriented crystal region (see FIG. 14 (C)).

0242From the above steps, the oxide semiconductor film 124b having the first crystal structure and the second crystal structure The oxide semiconductor film 124c having the above can be formed.

0243Next, after forming a mask on the oxide semiconductor film 124c having the second crystal structure, the mask is formed. It has an oxide semiconductor film 124b having a first crystal structure and a second crystal structure using a screw. Oxide that has a first crystal structure by selectively etching the oxide semiconductor film 124c A semiconductor film 125b and an oxide semiconductor film 125c having a second crystal structure are formed. Na Oxide semiconductor film 125b having a first crystal structure, and oxidation having a second crystal structure The material semiconductor film 125c is collectively referred to as an oxide semiconductor laminate 125. After this, remove the mask Leave.

0244Next, a pair of electrodes 126 are formed as in the first embodiment.

0245Next, insulation is performed on the gate insulating film 127, the pair of electrodes 126, and the oxide semiconductor laminate 125. Membrane 129 may be formed (see Figure 14 (D)).

0246The insulating film 129 appropriately uses the same material and manufacturing method as the insulating film 109 shown in the first embodiment. Can be formed.

0247Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transistor having an oxide semiconductor laminate having a hexagonal crystal region in the channel region Gista can be made.

0248In the present embodiment, the channel etching type transistor has been used for the description. It can be applied to channel protection type transistors.

0249The oxide semiconductor laminate has high crystallinity and uniformity in the region near the interface with the gate insulating film. Therefore, a transistor having stable electrical characteristics and high reliability can be obtained. Also, trigonal and / or hexagonal crystals that have hexagonal bonds on the ab plane and are c-axis oriented. By using an oxide semiconductor laminate having a crystal structure in the channel region of the transistor, Before and after light irradiation of the transistor, or before and after the bias-heat stress (BT) test , Transistor with small change in threshold voltage and stable electrical characteristics Stars can be made.

0250The oxynitride semiconductor has a smaller energy gap than the oxide semiconductor and is a carrier. Easy to shed. Therefore, an oxide semiconduct having a first crystal structure in contact with the gate insulating film 127 Transis having good electrical characteristics by forming the body film 125b with an oxynitride semiconductor film. Can be produced.

0251In addition, this embodiment can be appropriately combined with other embodiments.

0252(Embodiment 6) In the present embodiment, a transistor structure and fabrication different from those of the first to fifth embodiments The method will be described with reference to FIGS. 15 and 16. In this embodiment, the bottom gate type Transistor. In addition, a pair of electrodes is provided between the gate insulating film and the oxide semiconductor laminate. It is different from the fifth embodiment in that it is provided. It should be noted that the alternate long and short dash line in FIG. The cross-sectional view of GH corresponds to FIG. 15 (B). In FIG. 15 (A), the substrate 101 and the oxide The insulating film 102, the gate insulating film 137, and the insulating film 139 are omitted. Figure 16 shows Figure 1. It is sectional drawing explaining the manufacturing process of the transistor shown in 5 (B).

0253The transistor shown in FIG. 15 (B) has an oxide insulating film 102 formed on the substrate 101 and The gate electrode 138 formed on the oxide insulating film 102, and the oxide insulating film 102 and the gate. A gate insulating film 137 that covers the electrode 138, and one that functions as a source electrode and a drain electrode. Oxide semiconductor laminate in contact with a pair of electrodes 136, a gate insulating film 137, and a pair of electrodes 136 Has a body of 135. In addition, a gate insulating film 137, an oxide semiconductor laminate 135, and a pair. It may have an insulating film 139 covering the electrode 136.

0254The oxide semiconductor laminate 135 is oxidized having a first crystal structure in contact with the gate insulating film 137. A second object in contact with the semiconductor film 135b and the oxide semiconductor film 135b having the first crystal structure. It is characterized in that an oxide semiconductor film 135c having a crystal structure is laminated.

0255Further, the oxide semiconductor film 135b having the first crystal structure is used as a seed crystal, and the second crystal structure is used. The oxide semiconductor film 135c having the above is characterized by crystal growth.

0256The oxide semiconductor film 135b having the first crystal structure is one of a trigonal crystal and / or a hexagonal crystal. It has a wurtzite type crystal structure.

0257The oxide semiconductor film 135c having the second crystal structure is a trigonal crystal and / or a hexagonal crystal, and Y bFe₂O₄Type structure, Yb₂Fe₃O₇Crystals of either type structure or non-wurtzite type structure Has a structure.

0258The oxide semiconductor film having the first crystal structure and the oxide semiconductor film having the second crystal structure are Since both are trigonal and / or hexagonal, a hexagonal lattice image can be confirmed from the c-axis direction. ..

0259Oxide semiconductor film 135b having a first crystal structure, oxide semiconductor having a second crystal structure Each of the films 135c is a non-single crystal, and the entire oxide semiconductor film is in an amorphous state (Amol). It has a c-axis oriented crystal region rather than a fuss state). That is, the amorphous region and the c-axis orientation It has a crystalline region.

0260Here, the oxide semiconductor laminate 135 is used as an oxide semiconductor film having a first crystal structure. It has a two-layer structure consisting of 135b and an oxide semiconductor film 135c having a second crystal structure. As shown in the third and fourth embodiments of the application, an oxide semiconductor laminate having a three-layer structure may be used. ..

0261Next, the method of manufacturing the transistor shown in FIG. 15 (B) will be described with reference to FIG.

0262As shown in FIG. 16 (A), the oxide insulating film 102 is formed on the substrate 101 as in the first embodiment. To form. Next, the gate electrode 138 is formed on the oxide insulating film 102. Next, oxide A gate insulating film 137 is formed on the insulating film 102 and the gate electrode 138. Then the gate A pair of electrodes 136 are formed on the insulating film 137. Next, the gate insulating film 137 and a pair of electric wires The first oxide semiconductor film 133b is formed on the pole 136.

0263The gate electrode 138, the gate insulating film 137, and the first oxide semiconductor film 133b are respectively. , The gate electrode 108, the gate insulating film 107, and the second oxide semiconductor shown in the third embodiment. It can be formed by appropriately using the same material and manufacturing method as the film 103b.

0264Next, the first heat treatment is performed in the same manner as in the first embodiment. By the first heat treatment, the first acid Crystal growth begins from the surface of the compound semiconductor film 133b toward the gate insulating film 137, and the first The oxide semiconductor film 133b becomes an oxide semiconductor film 134b having a first crystal structure. Also The oxide semiconductor film 134b having the first crystal structure has a c-axis oriented crystal region.

0265Next, the second oxide semiconductor film 133 is placed on the oxide semiconductor film 134b having the first crystal structure. Form c (see Figure 16 (B)). The second oxide semiconductor film 133c is the third embodiment. It is formed by appropriately using the same material and manufacturing method as the third oxide semiconductor film 103c shown in 1. Can be done.

0266Next, the second heat treatment is performed in the same manner as in the third embodiment. By the heat treatment, the first crystal From the interface with the oxide semiconductor film 134b having a structure toward the second oxide semiconductor film 133c Crystal growth begins, and the second oxide semiconductor film 133c is an oxide having a second crystal structure. It becomes a semiconductor film 134c. Further, the oxide semiconductor film 134c having the second crystal structure is c. It has an axially oriented crystal region (see FIG. 16 (C)).

0267From the above steps, the oxide semiconductor film 134b having the first crystal structure and the second crystal structure The oxide semiconductor film 134c having the above can be formed.

0268Next, after forming a mask on the oxide semiconductor film 134c having the second crystal structure, the mask is formed. It has an oxide semiconductor film 134b having a first crystal structure and a second crystal structure using a screw. Oxide with a first crystal structure by selectively etching the oxide semiconductor film 134c A semiconductor film 135b and an oxide semiconductor film 135c having a second crystal structure are formed. Na Oxide semiconductor film 135b having a first crystal structure, and oxidation having a second crystal structure The material semiconductor film 135c is collectively referred to as an oxide semiconductor laminate 135. After this, remove the mask Leave.

0269Next, insulation is performed on the oxide insulating film 102, the pair of electrodes 136, and the oxide semiconductor laminate 135. Membrane 139 may be formed (see FIG. 16 (D)).

0270As the insulating film 139, the same material and manufacturing method as the insulating film 109 shown in the third embodiment are appropriately used. Can be formed.

0271Through the above steps, a hexagonal bond on the ab plane and a c-axis oriented trigonal crystal and / Or a transition having an oxide semiconductor laminate with hexagonal crystals in the channel region Can be produced.

0272In the present embodiment, the channel etching type transistor has been used for the description. It can be applied to channel protection type transistors.

0273The oxide semiconductor laminate has high crystallinity and uniformity in the region near the interface with the gate insulating film. Therefore, a transistor having stable electrical characteristics and high reliability can be obtained. Also, trigonal and / or hexagonal crystals that have hexagonal bonds on the ab plane and are c-axis oriented. Using an oxide semiconductor laminate having a crystal region of structure for the channel region of a transistor So, before and after irradiating the transistor with light, or before and after the bias-heat stress (BT) test. However, the amount of change in the threshold voltage of the transistor is small, and the transistor has stable electrical characteristics. An engineer can be made.

0274In addition, this embodiment can be appropriately combined with other embodiments.

0275(Embodiment 7) In the present embodiment, in the first to sixth embodiments, the plurality of gate electrodes are provided. The transistor will be described. Here, the theory is made using the transistor shown in the fifth embodiment. As will be described, it can be appropriately applied to the first to fourth embodiments and the sixth embodiment. To.

0276As in the fifth embodiment, as shown in FIG. 17, the oxide insulating film 102 is formed on the substrate 101. Then, on the oxide insulating film 102, the first gate electrode 148a and the first gate insulating film 147a To form. Next, on the first gate insulating film 147a, an oxide half having a first crystal structure Oxidation in which a conductor film 125b and an oxide semiconductor film 125c having a second crystal structure are laminated. Forming a semiconductor laminate 125, a pair of electrodes 126, and a second gate insulating film 147b. ..

0277Next, the area on the second gate insulating film 147b that overlaps with the oxide semiconductor laminate 125. A second gate electrode 148b is formed in the region. Next, the second gate insulating film 147b and the second An insulating film 129 may be formed as a protective film on the gate electrode 148b of the above.

0278The first gate electrode 148a and the second gate electrode 148b are the gates shown in the first embodiment. It can be formed in the same manner as the electrode 108.

0279The first gate insulating film 147a and the second gate insulating film 147b are the same as those shown in the first embodiment. It can be formed in the same manner as the insulating film 107.

0280The first gate electrode 148a and the second gate electrode 148b may be connected. this In this case, the first gate electrode 148a and the second gate electrode 148b have the same potential. The channel region is on the first gate electrode 148a side of the oxide semiconductor laminate 125, and the second game. Since it is formed on the electrode 148b side, it enhances the on-current and field effect mobility of the transistor. Can be

0281Alternatively, the first gate electrode 148a and the second gate electrode 148b are not connected and are different. An electric potential may be applied. In this case, the threshold voltage of the transistor can be controlled. To.

0282In the present embodiment, the pair of electrodes 126 are connected to the oxide semiconductor laminate 125 and the second game. Although it was formed between the insulating films 147b, the first gate insulating film 147a and the oxide semiconductor laminate It may be formed between the bodies 125.

0283Through the above steps, a transistor having a plurality of gate electrodes can be manufactured.

0284(Embodiment 8) In the present embodiment, at least a part of the drive circuit and a transistor arranged in the pixel portion are arranged on the same substrate. A mode for producing a display device having a gista will be described below.

0285The transistor arranged in the pixel portion is formed according to the first to seventh embodiments. Well Further, the transistors shown in the first to seventh embodiments are n-channel transistors. Therefore, among the drive circuits, the drive circuit that can be composed of n-channel transistors A part is formed on the same substrate as the transistor of the pixel portion.

0286FIG. 18 (A) shows one form of a block diagram of the active matrix type display device. Display device On the substrate 5300, the pixel unit 5301, the first scanning line drive circuit 5302, and the second scanning line It has a drive circuit 5303 and a signal line drive circuit 5304. Pixel unit 5301 has a plurality of signals The lines are arranged so as to extend from the signal line drive circuit 5304, and a plurality of scan lines are arranged in the first scan line drive times. It is arranged so as to extend from the road 5302 and the second scanning line drive circuit 5303. Scanning In the intersection region of the line and the signal line, pixels having a display element are arranged in a matrix. There is. The display device board 5300 is FPC (Flexible Printed C). Timing control circuit (both controller and control IC) via connection part such as ircuit) Is connected to).

0287In FIG. 18 (A), the first scanning line drive circuit 5302, the second scanning line drive circuit 5303, and the signal The line drive circuit 5304 is formed on the same substrate 5300 as the pixel unit 5301. so that Since the number of parts such as a drive circuit provided externally is reduced, the cost can be reduced. Well In addition, if a drive circuit is provided outside the board 5300, it becomes necessary to extend the wiring, and it becomes necessary to extend the wiring between the wiring. The number of connections increases. When the drive circuit is provided on the same board 5300, the number of connections between the wires is reduced. It is possible to improve the reliability or the yield.

0288Further, FIG. 18B shows one form of the circuit configuration of the pixel portion. Here, the VA liquid crystal display The pixel structure of the panel is shown.

0289In this pixel structure, one pixel has a plurality of pixel electrodes, and each pixel electrode has a transition. Is connected. Each transistor is configured to be driven by a different gate signal ing. That is, in a multi-domain designed pixel, it is applied to each pixel electrode. It has a configuration in which signals are controlled independently.

0290The gate wiring 602 of transistor 628 and the gate wiring 603 of transistor 629 , Separated so that different gate signals can be given. On the other hand, as a data line The functioning source or drain electrode 616 is transistor 628 and transistor 62. Commonly used in 9. Transistor 628 and transistor 629 are the first embodiment. The transistor of the seventh embodiment can be appropriately used.

0291The shapes of the first pixel electrode and the second pixel electrode are different and are separated by a slit. To. A second pixel electrode is formed so as to surround the outside of the first pixel electrode spreading in a V shape. .. The timing of the voltage applied to the first pixel electrode and the second pixel electrode is set by transistor 628. And the orientation of the liquid crystal is controlled by making it different by the transistor 629. Transi The star 628 is connected to the gate wiring 602, and the transistor 629 is connected to the gate wiring 603. doing. By giving different gate signals, the gate wiring 602 and the gate wiring 603 can be used. The operation timings of the Langista 628 and the transistor 629 can be different.

0292Further, a capacitive wiring 690 is provided, the gate insulating film is made of a dielectric material, and the first pixel electrode or the first pixel electrode or the first A capacitance electrode that is electrically connected to the pixel electrode of 2 and a holding capacitance are formed.

0293The first liquid crystal element 651 is formed by overlapping the first pixel electrode, the liquid crystal layer, and the counter electrode. It has been. Further, by overlapping the second pixel electrode, the liquid crystal layer, and the counter electrode, the second liquid crystal element Child 652 is formed. In addition, the first liquid crystal element 651 and the second liquid crystal element 65 per pixel. It is a multi-domain structure with 2.

0294The pixel configuration shown in FIG. 18B is not limited to this. For example, as shown in Fig. 18 (B). New switches, resistance elements, capacitive elements, transistors, sensors, or logic circuits in the pixels You may add any.

0295Further, in the present embodiment, the form of the VA type liquid crystal display panel is shown, but the form is not particularly limited. It can be applied to various types of liquid crystal display devices. For example, how to improve viewing angle characteristics As a method, a horizontal electric field method (IPS method) in which a horizontal electric field is applied to the liquid crystal layer with respect to the main surface of the substrate. Also called).

0296For example, as an IPS liquid crystal display panel, a liquid crystal showing a blue phase that does not use an alignment film is used. It is preferable to have. The blue phase is one of the liquid crystal phases and raises the temperature of the cholesteric liquid crystal. It is a phase that is expressed just before the transition from the cholesteric phase to the isotropic phase. Blue phase is narrow Since it is expressed only in the temperature range, a liquid crystal mixed with a chiral agent to improve the temperature range. The composition is used for the liquid crystal layer of the liquid crystal element. A liquid containing a liquid crystal showing a blue phase and a chiral agent The crystal composition has a short response rate of 1 msec or less and is optically isotropic, so no orientation treatment is required. And the viewing angle dependence is small.

0297In addition, in order to improve the moving image characteristics of the liquid crystal display device, multiple LEDs (light emission) are used as the backlight. A surface light source is configured by using a diode) light source or a plurality of EL light sources, and a surface light source is configured. Drive technology that independently drives each light source to be lit intermittently within one frame period (for example, field) (Sequential method, etc.) is also available. Three or more types of LEDs may be used as the surface light source. , A white light emitting LED may be used. Three or more types of light sources that exhibit different colors as surface light sources (For example, when using R (red), G (green), B (blue)), do not use color filters. Both can be displayed in color. Also, when using a white light emitting LED as the surface light source, the color is empty. -Provide a filter to display in color. Since multiple LEDs can be controlled independently, the liquid crystal layer It is also possible to synchronize the LED light emission timing according to the switching timing of the optical modulation of it can. Since the LED can be partially turned off, the black display area that occupies one screen in particular In the case of a video display with a large proportion of, the effect of reducing power consumption can be achieved.

0298Further, FIG. 18C shows one form of the circuit configuration of the pixel portion. Here, an organic EL element is used. The pixel structure of the display panel is shown.

0299An organic EL element is an electron and a hole from a pair of electrodes by applying a voltage to the light emitting element. Are injected into the membrane containing each luminescent organic compound, and an electric current flows. And those monsters The recombination of the rear (electrons and holes) causes the luminescent organic compound to form an excited state. Then, it emits light when its excited state returns to the ground state. From such a mechanism, like this A light emitting element is called a current excitation type light emitting element.

0300FIG. 18C shows a pixel configuration to which digital time gradation drive can be applied as a form of a semiconductor device. It is a figure which shows one form.

0301The configuration of pixels to which digital time gradation drive can be applied and the operation of pixels will be described. here Uses an oxide semiconductor film in the channel region to use n-channel transistors in one pixel. The form to be used is shown.

0302Pixel 6400 is a switching transistor 6401, a driving transistor 6402, It has a light emitting element 6404 and a capacitance element 6403. Switching transistor 64 In 01, the gate electrode is connected to the scanning line 6406, and the first electrode (source electrode and drain electrode) One of the poles is connected to the signal line 6405 and the second electrode (the other of the source and drain electrodes) ) Is connected to the gate electrode of the drive transistor 6402. Drive transistor 6 In 402, the gate electrode is connected to the power supply line 6407 via the capacitive element 6403, and the first electrode Is connected to the power supply line 6407, and the second electrode is in contact with the first electrode (pixel electrode) of the light emitting element 6404. It is being continued. The second electrode of the light emitting element 6404 corresponds to the common electrode 6408. Common electrode 6 The 408 is electrically connected to a common potential line formed on the same substrate.

0303A low power potential is set for the second electrode (common electrode 6408) of the light emitting element 6404. To. The low power supply potential is a low power supply based on the high power supply potential set in the power supply line 6407. Potential &lt;The potential that satisfies the high power supply potential, and for example, GND, 0V, etc. are set as the low power supply potential. It may be fixed. The potential difference between the high power supply potential and the low power supply potential is applied to the light emitting element 6404. Then, a current is passed through the light emitting element 6404 to cause the light emitting element 6404 to emit light, so that the power supply potential is high. So that the potential difference between and the low power supply potential is greater than or equal to the forward threshold voltage of the light emitting element 6404. Set each potential.

0304The capacitive element 6403 is omitted by substituting the gate capacitance of the driving transistor 6402. It is also possible. For the gate capacitance of the drive transistor 6402, see the channel region. A capacitance may be formed between the gate electrode and the gate electrode.

0305Here, in the case of the voltage input voltage drive method, the gate electrode of the drive transistor 6402 Will be in two states: the drive transistor 6402 is fully on and off. Input a video signal like this. That is, the drive transistor 6402 is operated in the linear region. To. Since the drive transistor 6402 operates in the linear region, it is the voltage of the power supply line 6407. A very high voltage is applied to the gate electrode of the driving transistor 6402. In addition, signal line 640 Apply a voltage equal to or higher than (power supply line voltage + Vth of drive transistor 6402) to 5.

0306Also, when analog gradation drive is performed instead of digital time gradation drive, the signal input is different. By making it possible, the same pixel configuration as in FIG. 18C can be used.

0307When performing analog gradation drive, a light emitting element 64 is attached to the gate electrode of the drive transistor 6402. Apply the forward voltage of 04 + the voltage of Vth or more of the driving transistor 6402. Light emitting element The forward voltage of 6404 refers to the voltage at which the desired brightness is obtained, and at least forward. Includes threshold voltage. It should be noted that the drive transistor 6402 operates in the saturation region. By inputting a video signal, a current can be passed through the light emitting element 6404. Drive tiger In order to operate the engineer 6402 in the saturation region, the potential of the power supply line 6407 is the drive transformer. Make it higher than the gate potential of Gista 6402. Light emission by making the video signal analog An analog gradation drive can be performed by passing a current corresponding to the video signal through the element 6404.

0308The pixel configuration shown in FIG. 18C is not limited to this. For example, as shown in Fig. 18 (C) New switches, resistance elements, capacitive elements, sensors, transistors, logic circuits, etc. May be added.

0309Next, the configuration of the light emitting element will be described with reference to the cross-sectional structure of the pixels shown in FIG. here Is an example of the n-channel type transistor for driving a light emitting element, and has a pixel cross-sectional structure. explain about. Used in the semiconductor devices of FIGS. 19 (A), 19 (B), and 19 (C). The light emitting element driving transistors 7011, 7021, and 7001 are described in the first embodiment. It can be manufactured in the same manner as the transistor shown in the seventh embodiment.

0310One of the first electrode or at least one of the second electrodes of the light emitting element uses a conductive film that transmits visible light. And take out the light emission from the light emitting element. As a structure focusing on the direction of extracting light emission , The light emitting element of the substrate is formed without going through the substrate on which the light emitting element and the transistor are formed. The light emission is taken out from the formed side through the upper surface injection structure and the substrate on which the light emitting element is formed. A bottom injection structure that emits light on the side where the optical element is not formed, and a light emitting element on the substrate are formed. There is a double-sided injection structure that extracts light emission on the other side of the substrate and on the other side of the substrate via the substrate. And the figure The pixel configuration shown in 18 (C) can be applied to a light emitting device having any emission structure.

0311A light emitting element having a bottom injection structure will be described with reference to FIG. 19 (A). Light emission of bottom injection structure The element emits light in the direction indicated by the arrow in FIG. 19 (A).

0312In FIG. 19A, the light emitting element driving transistor 7011 is shown in the first embodiment. A form in which a channel type transistor is used is shown, but the present invention is not particularly limited.

0313In FIG. 19 (A), the source electrode or drain power of the light emitting element driving transistor 7011 is shown. On the translucent first electrode 7017, which is electrically connected to the pole, the EL layer 7014, the second Electrodes 7015 are stacked in order.

0314The first electrode 7017 uses a conductive film that transmits visible light. As a conductive film that transmits visible light For example, indium oxide containing tungsten oxide, indium containing tungsten oxide. Zinc oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide Things, indium tin oxide (hereinafter referred to as ITO), indium zinc oxide, silicon oxide There is indium tin oxide to which is added. Also, the degree to which light is transmitted (preferably 5n) A metal thin film of m to 30 nm) can also be used. For example, a with a film thickness of 20 nm The luminium film can be used by laminating it on another light-transmitting conductive film.

0315The second electrode 7015 is preferably made of a material that efficiently reflects the light emitted by the EL layer 7014. Na This is because the light extraction efficiency can be improved. The second electrode 7015 has a laminated structure. May be. For example, a conductive film that transmits visible light is used on the side in contact with the EL layer 7014, and others A film 7016 that blocks light can also be laminated on the side. As a film that blocks light, A metal film or the like that efficiently reflects the light emitted by the EL layer is preferable, but for example, a black pigment is added. Resin or the like can also be used.

0316One of the first electrode 7017 and the second electrode 7015 functions as an anode, and the other is negative. Acts as a pole. For the electrode that functions as an anode, a substance with a large work function is preferable, and it is negative. A substance having a small work function is preferable for the electrode that functions as a pole.

0317Materials with a large work function include, for example, ZrN, Ti, W, Ni, Pt, Cr, etc., and I. TO, In-Zn-O, etc. can be used. As a material with a small work function, Li Alkali metals such as Cs and Alkali earth metals such as Mg, Ca and Sr, and these In addition to alloys containing (Mg: Ag, Al: Li, etc.), rare earth metals such as Yb and Er are used. be able to.

0318When comparing the power consumption, the first electrode 7017 functions as a cathode and the second electrode is used. By using 7015 as the anode, the voltage rise of the drive circuit can be suppressed and the power consumption can be reduced. Therefore, it is preferable.

0319The EL layer 7014 may include at least a light emitting layer, and even if it is composed of a single layer, there are a plurality of EL layers 7014. Layers may be laminated. As a configuration composed of a plurality of layers, holes are formed from the anode side. In the form of a laminated structure of an injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. Can be mentioned. It is not necessary to provide all of these layers in the EL layer 7014. It can also be provided in duplicate. In addition to the charge generation layer as an intermediate layer, it is also an electron relay layer. Other configurations can be added as appropriate.

0320Further, the light emitting element 7012 includes a partition wall 7019 that covers an end portion of the first electrode 7017. Septum 7019 is an organic resin film such as polyimide, acrylic, polyamide, epoxy, etc. An edge film or an organic polysiloxane film can be applied. Especially, the song where the side of the partition wall 7019 is continuous It is preferable to use a photosensitive resin material to form an inclined surface that is formed with a certain ratio. Good. When a photosensitive resin material is used for the partition wall 7019, the step of forming a resist mask Can be omitted. Further, the partition wall can be formed of an inorganic insulating film. Inorganic insulating film Can be used for the partition wall to reduce the amount of water contained in the partition wall.

0321The color filter layer 7033 is provided between the light emitting element 7012 and the substrate 7010. (See Figure 19 (A)). By applying a configuration that emits white light to the light emitting element 7012 , The light emitted by the light emitting element 7012 passes through the color filter layer 7033, and the insulating film 7032, It is injected through the gate insulating film 7031, the oxide insulating film 7030, and the substrate 7010. To.

0322Multiple types of color filter layers 7033 may be formed, for example, a red color for each pixel. A filter layer, a blue color filter layer, a green color filter layer, etc. can be provided. To. The color filter layer 7033 can be used in a droplet ejection method such as an inkjet method, a printing method, or the like. Or it was to form respectively an etching method using photolithography technique.

0323In addition, the color filter layer 7033 is covered with the overcoat layer 7034, and further protective insulation is provided. Cover with membrane 7035. In FIG. 19 (A), the overcoat layer 7034 has a thin film thickness. As shown in the above, the overcoat layer 7034 uses a resin material such as acrylic resin and is colored. -Has the function of flattening the unevenness caused by the filter layer 7033.

0324In addition, the insulating film 7032, the color filter layer 7033, the overcoat layer 7034, and the retainer The contact hole formed in the protective insulating film 7035 and reaching the drain electrode is the partition wall 7. Place it at a position that overlaps with 019.

0325Next, a light emitting element having a double-sided injection structure will be described with reference to FIG. 19 (B). Double-sided injection structure The light emitting element of No. 1 emits light in the direction indicated by the arrow in FIG. 19 (B).

0326In FIG. 19B, the light emitting element driving transistor 7021 is shown in the first embodiment. A form in which a channel type transistor is used is shown, but the present invention is not particularly limited.

0327In FIG. 19B, the source electrode or drain power of the light emitting element driving transistor 7021 is shown. On the translucent first electrode 7027, which is electrically connected to the pole, EL layer 7024, second Electrodes 7025 are stacked in order.

0328The first electrode 7027 and the second electrode 7025 use a conductive film that transmits visible light. Visible As the conductive film that transmits light, it can be used for the first electrode 7017 in FIG. 19 (A). The material can be applied. Therefore, the detailed explanation is based on the explanation of the first electrode 7017. To.

0329Either the first electrode 7027 or the second electrode 7025 functions as an anode. The other functions as a cathode. A substance with a large work function is preferable for the electrode that functions as an anode. Furthermore, a substance having a small work function is preferable for the electrode that functions as a cathode.

0330The EL layer 7024 may be composed of a single layer or may have a plurality of layers laminated. EL As the layer 7024, the structure and material that can be used for the EL layer 7014 shown in FIG. 19 (A). Fees can be applied. Therefore, for the detailed explanation, the explanation of the EL layer 7014 is used.

0331Further, the light emitting element 7022 includes a partition wall 7029 that covers the end portion of the first electrode 7027. Septum 7029 applies configurations and materials that can be used for bulkhead 7019 in FIG. 19 (A). Can be Therefore, the detailed explanation is based on the explanation of the partition wall 7019.

0332Further, in the case of the element structure shown in FIG. 19 (B), the light emitted from the light emitting element 7022 is an arrow. As shown by the mark, it is injected to both the second electrode 7025 side and the first electrode 7027 side, and the first electricity is generated. One of the lights emitted to the pole 7027 side is the insulating film 7042, the gate insulating film 7041, and the oxide. It is injected through the insulating film 7040 and the substrate 7020.

0333Further, in the structure of FIG. 19B, when performing full-color display, for example, the light emitting element 70 As 22, a green light emitting element is used, one adjacent light emitting element is used as a red light emitting element, and the other is used as a red light emitting element. The light emitting element is a blue light emitting element. In addition, not only 3 types of light emitting elements but also white elements are added 4 A light emitting display device capable of full-color display with various types of light emitting elements may be manufactured.

0334Next, a light emitting element having a top injection structure will be described with reference to FIG. 19 (C). Top injection structure The light emitting element of No. 1 emits light in the direction indicated by the arrow in FIG. 19 (C).

0335In FIG. 19C, the light emitting element driving transistor 7001 is shown in the first embodiment. A form in which a channel type transistor is used is shown, but the present invention is not particularly limited.

0336In FIG. 19C, the source electrode or drain power of the light emitting element driving transistor 7001 is shown. EL layer 7004, second electrode 7005 on the first electrode 7003 electrically connected to the pole Are stacked in order.

0337The first electrode 7003 is preferably made of a material that efficiently reflects the light emitted by the EL layer 7004. Na This is because the light extraction efficiency can be improved. The first electrode 7003 has a laminated structure. May be. For example, a conductive film that transmits visible light is used on the side in contact with the EL layer 7004, and others It is also possible to use a laminated film that blocks light. The EL layer is a film that blocks light. A metal film or the like that efficiently reflects the emitted light is preferable, but for example, a resin or the like to which a black pigment is added is used. It can also be used.

0338The second electrode 7005 uses a conductive film that transmits visible light. As a conductive film that transmits visible light Can be applied with materials that can be used for the first electrode 7017 in FIG. 19 (A). To. Therefore, the detailed description is based on the description of the first electrode 7017.

0339Either the first electrode 7003 or the second electrode 7005 functions as an anode. The other functions as a cathode. A substance with a large work function is preferable for the electrode that functions as an anode. Furthermore, a substance having a small work function is preferable for the electrode that functions as a cathode.

0340The EL layer 7004 may be composed of a single layer or may have a plurality of layers laminated. EL As the layer 7004, the structure and material that can be used for the EL layer 7014 shown in FIG. 19 (A). Fees can be applied. Therefore, for the detailed explanation, the explanation of the EL layer 7014 is used.

0341Further, the light emitting element 7002 includes a partition wall 7009 that covers an end portion of the first electrode 7003. Septum 7009 applies configurations and materials that can be used for bulkhead 7019 in FIG. 19 (A). Can be Therefore, the detailed explanation is based on the explanation of the partition wall 7019.

0342Further, in FIG. 19C, the source electrode of the light emitting element driving transistor 7001 or Drain electrodes are provided on the gate insulating film 7051, the protective insulating film 7052, and the insulating film 7055. It is electrically connected to the first electrode 7003 through a contact hole. Flattening insulation Membrane 7053 is made of polyimide, acrylic, benzocyclobutene, polyamide, epoxy, etc. A resin material can be used. In addition to the above resin materials, low dielectric constant materials (low-k materials) Material), siloxane resin, etc. can be used. Insulation formed from these materials The flattening insulating film 7053 may be formed by laminating a plurality of films. Flattening insulating film 70 The forming method of 53 is not particularly limited, and depending on the material, a sputtering method, an SOG method, or a spinco is used. Tote, dip, spray coating, droplet ejection method (inkjet method, screen printing, off) Set printing, etc.) can be used.

0343Further, in the structure of FIG. 19C, when performing full-color display, for example, the light emitting element 70 As 02, a green light emitting element is used, one adjacent light emitting element is used as a red light emitting element, and the other is used. The light emitting element is a blue light emitting element. In addition, not only 3 types of light emitting elements but also white elements are added 4 A light emitting display device capable of full-color display with various types of light emitting elements may be manufactured.

0344Further, in the structure of FIG. 19C, the plurality of light emitting elements to be arranged are all white light emitting elements. In addition, a sealing substrate having a color filter or the like is arranged above the light emitting element 7002. , A light emitting display device capable of full-color display may be manufactured. Shows a single color such as white Full-color display is performed by forming materials and combining color filters and color conversion layers. I can.

0345Of course, monochromatic light emission may be displayed. For example, forming a lighting device using white light emission Alternatively, a monochromatic light emitting device may be used to form an area color type light emitting device.

0346Further, if necessary, an optical film such as a polarizing film such as a circular polarizing plate may be provided.

0347A transistor that controls the drive of the light emitting element (transistor for driving the light emitting element) and a light emitting element An example in which the child is electrically connected is shown, but the transistor for driving the light emitting element and the light emitting element are shown. A current control transistor may be connected between them.

0348The semiconductor device shown in the present embodiment is not limited to the configuration shown in FIG. Various modifications based on the technical idea of the present invention are possible.

0349(Embodiment 9) The semiconductor device disclosed in this specification shall be applied to various electronic devices (including gaming machines). Can be done. Electronic devices include, for example, television devices (televisions or televisions). Receivers), monitors for computers, digital cameras, digital video cameras Cameras such as LA, digital photo frames, mobile phones (also called mobile phones and mobile phone devices) ), Portable game machines, personal digital assistants, audio playback devices, large game machines such as pachinko machines, etc. Can be mentioned. A description of the embodiment of the electronic device including the display device described in the above embodiment. I will reveal.

0350FIG. 20A shows a portable information terminal, which includes a main body 3001, a housing 3002, and a display unit 300. It is composed of 3a, 3003b, etc. Display 3003b has a touch input function Touch the keyboard button 3004 displayed on the display 3003b. By doing so, you can operate the screen and enter characters. Of course, touch the display unit 3003a It may be configured as a panel having an input function. It is shown in Embodiment 1 to Embodiment 7. Using a transistor as a switching element, the liquid crystal panel and organic light emission shown in Embodiment 8 By making a panel and applying it to the display units 3003a and 3003b, a portable information end Can be the end.

0351The portable information terminal shown in Fig. 20 (A) has various information (still images, moving images, text images, etc.). ) Display function, calendar, date or time display function on the display unit, table on the display unit A function to operate or edit the indicated information, processing by various software (programs) It can have a function to control, and the like. In addition, external connection terminals (on the back and sides of the housing) It may be configured to include an earphone terminal, a USB terminal, etc.), a recording medium insertion unit, and the like.

0352In addition, the portable information terminal shown in FIG. 20 (A) may be configured to be able to send and receive information wirelessly. Good. Purchase and download desired book data, etc. from the e-book server wirelessly It is also possible to configure it.

0353The portable information terminal shown in FIG. 20 (A) has two display units 3003a and 3003b. One of them can be removed, and the figure when it is removed is shown in FIG. 20 (B). table The display unit 3003a is also a panel with a touch input function, further reducing the weight when carrying it. It is convenient because you can hold the housing 3002 with one hand and operate it with the other hand. Is.

0354Furthermore, the housing 3002 shown in Fig. 20 (B) is provided with an antenna, microphone function, and wireless function. It may be used as a mobile phone.

0355FIG. 20C shows a form of a mobile phone. Mobile phone 500 shown in Fig. 20 (C) In addition to the display unit 5001 built into the housing, 5 is a display panel attached to the hinge 5002. It is equipped with flannel 5003, operation buttons 5004, speaker, microphone, etc.

0356In the mobile phone 5005 shown in FIG. 20 (C), the display panel 5003 slides to display the display unit. It overlaps with the 5001 and also functions as a translucent cover. Display panel Is the surface of the 5003 on the substrate side and the surface opposite to the substrate shown in FIG. 19 (B) of the eighth embodiment? It is a display panel using a light emitting element having a double-sided injection structure that extracts light from the light.

0357Moreover, since the display panel 5003 uses a light emitting element having a double-sided injection structure, the display unit 5001 It is possible to display even when it is overlapped with, and the user displays both, and both displays are visible. You can also do it. The display panel 5003 is translucent, and the other side of the display panel is transparent. It is a visible panel. For example, the map is displayed on the display unit 5001 and the user's location is poi. By displaying the computer on the display panel 5003, it is possible to provide a state that is easy to recognize. Wear.

0358Further, when the mobile phone 5005 is provided with an image sensor and used as a videophone, a plurality of phases are used. Since you can talk with multiple people while displaying your hand, you can also hold a video conference etc. .. For example, the face of one or more opponents is displayed on the display panel 5003, and the display unit 50 By displaying another face on 01, the user can have a conversation while looking at the faces of two or more people. Can be done.

0359Also, touch the touch input button 5006 displayed on the display panel 5003 with your finger. You can enter the information with. Also, operations such as making a phone call or typing an email Slide the display panel 5003 and touch the operation button 5004 with your finger etc. Can be done more.

0360FIG. 20 (D) shows a form of the television device 9600. Television device 9 The 600 has a display unit 9603 incorporated in the housing 9601. By the display unit 9603 It is possible to display an image. Also, here, the stand 9605 with a built-in CPU Shows the configuration that supports the housing 9601. Shown in Embodiment 1 to Embodiment 7 By applying the transistor to the display unit 9603, it becomes a television device 9600. Can be

0361The operation of the television device 9600 is performed by the operation switch provided in the housing 9601 and the separate remote control. It can be done by a control machine. In addition, from the remote control controller to the remote controller A display unit for displaying the information to be output may be provided.

0362The television device 9600 is configured to include a receiver, a modem, and the like. To the receiver It can receive more general TV broadcasts, and can be wired or wireless via a modem. One-way (sender to recipient) or two-way by connecting to a communication network It is also possible to perform information communication (between the sender and the receiver, or between the recipients, etc.).

0363In addition, the television device 9600 has an external connection terminal 9604 and a storage medium playback / recording unit 96. 02, equipped with an external memory slot. External connection terminal 9604 is a USB cable, etc. It can be connected to various cables, and data communication with personal computers etc. is possible. is there. Storage medium playback In the recording unit 9602, a disc-shaped recording medium is inserted and recorded on the recording medium. It is possible to read the stored data and write it to the recording medium. Also, external memory Tables of images and videos stored in the external memory 9606 inserted in the slot It is also possible to project it on the display 9603.

0364As described above, the configurations, methods, etc. shown in the present embodiment are suitable with the configurations, methods, etc. shown in other embodiments. It can be used in any combination.

0365101 board 102 Oxide insulating film 103a Oxide semiconductor film 103b Oxide semiconductor film 103c oxide semiconductor film 104a Oxide semiconductor film 104b Oxide semiconductor film 104c oxide semiconductor film 105 Oxide semiconductor laminate 105a oxide semiconductor film 105b oxide semiconductor film 105c oxide semiconductor film 106 electrodes 107 Gate insulating film 108 Gate electrode 109 Insulation film 113a Oxide semiconductor film 113b Oxide semiconductor film 113c Oxide semiconductor film 114a Oxide semiconductor film 114b oxide semiconductor film 114c oxide semiconductor film 115 Oxide semiconductor laminate 115a oxide semiconductor film 115b oxide semiconductor film 115c oxide semiconductor film 116 Electrodes 117 Gate insulating film 118 Gate electrode 119 Insulation film 120 wiring 123b oxide semiconductor film 123c oxide semiconductor film 124b Oxide semiconductor film 124c Oxide semiconductor film 125 Oxide semiconductor laminate 125b oxide semiconductor film 125c oxide semiconductor film 126 Electrodes 127 Gate insulating film 128 Gate electrode 129 Insulation film 133b Oxide semiconductor film 133c Oxide semiconductor film 134b Oxide semiconductor film 134c Oxide semiconductor film 135 Oxide semiconductor laminate 135b oxide semiconductor film 135c oxide semiconductor film 136 Electrodes 137 Gate insulating film 138 Gate electrode 139 Insulating film 147a Gate insulating film 147b Gate insulating film 148a Gate electrode 148b Gate electrode 602 Gate wiring 603 Gate wiring 616 Source or drain electrode 628 transistor 629 transistor 651 Liquid crystal element 652 Liquid crystal element 690 Capacitive wiring 2000 crystal structure 2001 Crystal structure 3001 body 3002 housing 3003a Display 3003b Display 3004 keyboard buttons 5001 Display 5002 hinge 5003 display panel 5004 Operation buttons 5005 mobile phone 5006 Touch input button 5300 board 5301 Pixel part 5302 Scan line drive circuit 5303 Scan line drive circuit 5304 Signal line drive circuit 6400 pixels 6401 Switching transistor 6402 Drive transistor 6403 Capacitive element 6404 Light emitting element 6405 signal line 6406 scan line 6407 Power line 6408 Common electrode 7001 Transistor for driving light emitting element 7002 light emitting element 7003 electrode 7004 EL layer 7005 electrode 7009 bulkhead 7010 board 7011 Transistor for driving light emitting element 7012 Light emitting element 7014 EL layer 7015 electrode 7016 membrane 7017 electrode 7019 Septum 7020 board 7021 Transistor for driving light emitting element 7022 Luminescent element 7024 EL layer 7025 electrode 7027 electrode 7029 bulkhead 7030 Oxide insulating film 7031 Gate insulating film 7032 insulating film 7033 Color filter layer 7034 Overcoat layer 7035 Protective insulating film 7040 Oxide insulating film 7041 Gate insulating film 7042 Insulation film 7051 Gate insulating film 7052 Protective insulating film 7053 Flattening insulating film 7055 Insulation film 9600 television device 9601 housing 9602 Storage medium playback recording unit 9603 Display 9604 External connection terminal 9605 stand 9606 external memory