Wiring board, semiconductor device, and its manufacturing method

The present invention relates to a wiring substrate formed by using a droplet ejection method typified by an inkjet method, a semiconductor device having a semiconductor element, and a method for manufacturing the same.

Conventionally, a so-called active matrix drive type display panel composed of semiconductor elements represented by a thin film transistor (hereinafter, also referred to as TFT) or a MOS transistor, or a semiconductor integrated circuit has been subjected to a light exposure process using a photomask (hereinafter, also referred to as TFT). , Shown as a photolithography process), manufactured by patterning various thin films.

In the photolithography step, a resist is applied to the entire surface of the substrate, prebaked, and then irradiated with ultraviolet rays or the like through a photomask to form a resist pattern by development. After that, using the resist pattern as a mask pattern, a thin film (a film formed of a semiconductor material, an insulator material, or a conductor material) existing other than a film pattern or a portion to be a wiring is etched and removed to obtain a film pattern. And wiring is formed.

Further, in order to reduce the loss of the raw material required for film formation, Patent Document 1 describes a technique for forming a film on a semiconductor wafer using a device capable of continuously ejecting a resist from a nozzle in a linear shape having a small diameter. ..<patcit num="1"><text>Japanese Unexamined Patent Publication No. 2000-188251</text></patcit>

<p> However, in the wiring and film pattern forming process using the conventional photolithography process, most of the wiring, film pattern and resist materials are wasted, and the number of steps for forming the wiring and mask pattern is large. There is a problem that the throughput is reduced.</p><p> Further, in the exposure apparatus used in the photolithography process, it is difficult to expose a large-area substrate at one time. Therefore, in the method of manufacturing a semiconductor device using a large-area substrate, there is a problem that a plurality of exposure times are required and inconsistency with adjacent patterns occurs, resulting in a decrease in yield.</p><p> Further, in order to form a fine semiconductor element having a small occupied area by the droplet ejection method, it is necessary to eject a raw material solution having a small droplet diameter. For this purpose, the diameter of the discharge port may be reduced, but in this case, the composition of the raw material solution adheres to the tip of the discharge port, dries, and solidifies, causing clogging and the like, and a certain amount of the raw material solution. Is difficult to continuously and stably discharge. As a result, there is a problem that the throughput and yield of the semiconductor device formed by the semiconductor element are lowered.</p><p> The present invention has been made in view of such a situation, and an object of the present invention is to provide a method for forming wiring on a large-area substrate with a small number of steps, and a wiring substrate formed by the method.</p><p> Another object of the present invention is to provide a semiconductor device capable of reducing costs and improving throughput by reducing the number of steps and raw materials, and having a semiconductor element having a fine structure, and a method for manufacturing the same.</p>

<p> In the present invention, a composition formed of metal particles and an organic resin provided on a substrate is irradiated with laser light, and a part of the metal particles is fired to form a conductive layer typified by wiring, electrodes and the like. The gist is to form a substrate to have.</p><p> Another gist of the present invention is to form a semiconductor device having the fired conductive layer as wiring or electrodes.</p><p> In the composition, metal particles are dispersed or dissolved in one or more organic resins selected from organic resins that function as binders, solvents, dispersants, and dressings. Therefore, by irradiating the composition with laser light, a part of the organic resin evaporates, and the metal particles are fired and adhered to each other to form a conductive layer. At this time, the composition remains on one side surface or both side surfaces of the conductive layer.</p><p> Further, by appropriately controlling the width of the beam spot of the laser beam, a conductive layer having an arbitrary width can be formed. Therefore, by irradiating a laser beam having a beam spot width narrower than the width of the composition using a laser beam direct drawing device or the like, a conductive layer having a narrower width (typically, 10 μm or less, preferably 0.3). It is possible to form ~ 1 μm, more preferably 0.5 ~ 0.8 μm). By using such a conductive layer for the gate electrode, it is possible to form a semiconductor device having a short channel structure, and it is possible to manufacture a semiconductor device having a high-speed operation and a high-density integrated device. Is.</p><p> Further, in the composition remaining on one side surface or both side surfaces of the conductive layer, metal particles are dispersed in an organic resin functioning as a solvent. Therefore, it exhibits conductivity or insulation depending on the density of metal particles. That is, when the density of the metal particles is high and the contact area between the particles is high, the composition provided on the side of the conductive layer exhibits conductivity. On the other hand, when the density of the metal particles is low and the metal particles are surrounded by an organic resin, the composition remaining on one side surface or both side surfaces of the conductive layer exhibits insulating properties. Therefore, when the composition remaining on one side surface or both side surfaces of the conductive layer exhibits insulating properties, only the conductive layer formed by irradiation with laser light functions as a wiring or an electrode. Therefore, even in a conductive layer having a large aspect ratio (vertical length&gt; horizontal length), it is possible to form a stable conductive layer that does not easily fall over. Further, it is possible to increase the coverage (coverage) of the insulating layer and the semiconductor layer to be formed later, and it is possible to form a highly reliable semiconductor element.</p><p> The present invention includes the following configurations.</p><p> One of the present invention has a wiring formed on a substrate, the wiring is a conductive layer in which the first metal particles are fired, and the second metal particles are dispersed on the side surface of the wiring. An organic resin layer is provided, and the first metal particles and the second metal particles are wiring substrates composed of the same metal element. The metal element at this time may be composed of a plurality of metal elements.</p><p> Further, a conductive layer, an insulating layer or a semiconductor layer in contact with the wiring and the organic resin layer may be formed. The organic resin layer is provided only on both side surfaces or one side surface of the wiring. At this time, the wiring is linear.</p><p> In addition, the proportion of metal elements in the wiring is larger than the proportion of metal elements in the organic resin layer.</p><p> Further, the ratio of the organic resin in the wiring is smaller than the ratio of the organic resin in the organic resin layer.</p><p> The cross section of the wiring is a substantially right-angled quadrangle or a substantially trapezoidal shape. In the case of a trapezoidal shape, the width of the wiring in contact with the substrate may be narrower than the width of the wiring surface. Further, the width of the wiring in contact with the substrate may be wider than the width of the wiring surface.</p><p> The width of the wiring is 0.3 μm or more and 1 μm or less, preferably 0.5 μm or more and 0.8 μm or less.</p><p> Further, one of the present inventions is to eject a composition formed of metal particles and an organic resin onto a substrate to form a pattern, and irradiate a part of the pattern with laser light to irradiate a part of the pattern with a laser beam to contain the metal particles contained in the pattern. This is a method for manufacturing a wiring board, which comprises firing a part of the above to form a wiring.</p><p> Further, in one of the present inventions, a composition formed of metal particles and an organic resin was discharged onto a substrate to form a pattern, and a part of the pattern was irradiated with laser light, and the laser light was irradiated. It is a method of manufacturing a wiring board characterized by improving the conductivity of a region.</p><p>The laser beam is preferably scanned in a direction parallel to the long axis of the pattern. The laser light is a continuously oscillating laser light or a pulse oscillating laser light.</p><p> Further, one of the present invention is a semiconductor device composed of a semiconductor element having the wiring as a gate electrode. Examples of the semiconductor element include TFT, field effect transistor (FET), MOS transistor, bipolar transistor, organic semiconductor transistor, MIM element, storage element, diode, photoelectric conversion element, capacitive element, resistance element and the like. Examples of the TFT include a forward stagger type TFT, a reverse stagger type TFT (channel etch type TFT or a channel protection type TFT), a bottom gate TFT, and a top gate TFT coplanar type TFT.</p><p> Further, one of the present inventions is to eject a composition formed of metal particles and an organic resin onto a substrate to form a pattern, and irradiate a part of the pattern with laser light to irradiate a part of the pattern with metal particles contained in the pattern. This is a method for manufacturing a semiconductor device, which comprises firing a part of the above to form a gate electrode, and then forming a thin film on a region of the gate electrode and a mask pattern that has not been irradiated with laser light.</p><p> Further, in the present invention, examples of the semiconductor device include an integrated circuit composed of semiconductor elements, a display device, a wireless tag, an IC tag, and the like. Typical display devices include liquid crystal display devices, light emitting display devices, DMDs (Digital Micromirror Devices), PDPs (Plasma Display Panels), and FEDs (Field Emission Display). , Display devices such as electrophoretic display devices (electronic paper).</p><p> In the present invention, the display device refers to a device using a display element, that is, an image display device. In addition, there is a connector on the display panel, for example, a module with a flexible printed circuit (FPC) or TAB (Tape Automated Bonding) tape or TCP (Tape Carrier Package) attached, and a printed wiring board at the end of the TAB tape or TCP. The display device shall include all modules provided or modules in which an IC (integrated circuit) or CPU is directly mounted on the display element by the COG (Chip On Glass) method.</p>

<p> As in the present invention, by directly irradiating a part of the composition formed of the metal particles and the organic resin with a laser beam and firing the metal particles, a conductive layer having a fine width is used without using a photomask. Can be formed. Further, the width of the laser beam is narrow, and by irradiating a part of the composition with the laser beam, the film pattern formed by the droplet ejection method can be finely processed, and a semiconductor element having a fine structure can be formed. .. Furthermore, since it is possible to form a semiconductor element having a short channel length by using the conductive layer as a gate electrode, it is possible to manufacture a semiconductor device in which semiconductor elements capable of high-speed operation are integrated at high density. Is possible.</p><p> Further, it is possible to form a conductive layer by firing the metal particles contained in the composition dropped by the droplet ejection method without heat treatment using a furnace or the like. Therefore, it is possible to manufacture a wiring board and a semiconductor device using a plastic substrate having low heat resistance or a substrate having flexibility. Therefore, it is possible to manufacture a lightweight and thin semiconductor device, a liquid crystal television having the semiconductor device, and an EL television.</p><p> Further, when forming the film pattern, by using the droplet ejection method, the relative position between the nozzle, which is the ejection port of the droplet containing the material of the film, and the substrate can be changed to an arbitrary location. Droplets can be ejected to. Further, the thickness and thickness of the film pattern to be formed can be adjusted by the relative relationship between the nozzle diameter, the discharge amount of the droplet, and the moving speed between the nozzle and the substrate on which the discharged material is formed. Therefore, the film pattern can be accurately ejected and formed at a desired location even on a large-area substrate having a side of more than 1 to 2 m. In addition, since inconsistency with adjacent film patterns does not occur, the yield can be improved. As a result, it is possible to manufacture a semiconductor device with a high yield with a small number of steps.</p><p> Further, a liquid crystal television and an EL television having a semiconductor device formed by the above manufacturing process can be manufactured at low cost and with high throughput and yield.</p>

Hereinafter, the best mode for carrying out the invention will be described with reference to the drawings. However, those skilled in the art can easily understand that the present invention can be carried out in many different modes, and that the forms and details thereof can be variously changed without departing from the spirit and scope of the present invention. Will be done. Therefore, the present invention is not construed as being limited to the description of the present embodiment. Further, common parts in each drawing are designated by the same reference numerals, and detailed description thereof will be omitted.

(Embodiment 1) In the present embodiment, a process of irradiating a laser beam (hereinafter, also referred to as a laser beam) to form a narrow wiring will be described with reference to FIGS. 1 to 3.

FIG. 2 is a top view of the substrate 101 in which the pixels are arranged in a matrix. On the substrate 101, a second conductive layer 113 that functions as a gate wiring for a semiconductor element to be formed later and a first conductive layer 105 that functions as a gate electrode connected to the second conductive layer 113 are shown by solid lines. The broken line indicates the source wiring, semiconductor region, source electrode, drain electrode, pixel electrode, and the like of the semiconductor element to be formed later.

FIG. 1 is a perspective view of a cross section of AB in FIG. 2 as viewed from the front. As shown in FIG. 1 (A), the material of the first pattern is ejected onto the substrate 101 by the droplet ejection method and dried to form the first pattern 102. Here, the droplet ejection method refers to a method of ejecting droplets of the prepared composition from fine holes to form a pattern having a predetermined shape.

As the substrate 101, a glass substrate, a quartz substrate, a ceramic substrate such as alumina, a plastic substrate, a silicon wafer, a metal plate, or the like can be used. When a glass substrate is used as the substrate 101, a large area substrate such as 320 mm × 400 mm, 370 mm × 470 mm, 550 mm × 650 mm, 600 mm × 720 mm, 680 mm × 880 mm, 1000 mm × 1200 mm, 1100 mm × 1250 mm, 1150 mm × 1300 mm is used. be able to.

Typical examples of plastic substrates are PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PES (polyethersulfone), polypropylene, polypropylene sulfide, polycarbonate, polyetherimide, polyphenylene sulfide, polyphenylene oxide, polysulfone, or polyphthalate. Examples thereof include a plastic substrate made of amide, a substrate made of an organic material in which inorganic particles having a diameter of several nm are dispersed, and the like. Further, the surface of the substrate does not have to be flat, and may have irregularities or curved surfaces.

As the material to be discharged from the discharge port as the material of the first pattern, a composition in which a conductor (metal particles) is dissolved or dispersed in an organic resin is used. Metal particles include metals such as Ag, Au, Cu, Ni, Pt, Pd, Ir, Rh, W, Al, Ta, Mo, Cd, Zn, Fe, Ti, Si, Ge, Zr, Ba, and silver halides. Fine particles of silver or dispersible nanoparticles can be used. Alternatively, an oxide conductive material such as ITO (indium tin oxide alloy) used as a transparent conductive film, ITO having silicon oxide, organic indium, organic tin, and zinc oxide (ZnO) can be used. Further, the conductive layer made of these materials can be laminated to form the first pattern 102. Further, as the organic resin, one or more selected from organic resins functioning as binders, solvents, dispersants, and coating agents for metal particles can be used. Typical examples include polyimide, acrylic, novolak resin, melamine resin, phenol resin, epoxy resin, silicon resin, furan resin, diallyl phthalate resin, and known organic resins.

The viscosity of the composition is preferably 5 to 20 mPa · s or less, in order to prevent drying from occurring and to allow the metal particles to be smoothly discharged from the discharge port. The surface tension is preferably 40 mN / m. The viscosity of the composition may be appropriately adjusted according to the solvent used and the intended use. As an example, the viscosity of a composition in which ITO, ITO having silicon oxide, organic indium, and organic tin are dissolved or dispersed in an organic resin is 5 to 20 mPa · s, and the viscosity of a composition in which silver is dissolved or dispersed in an organic resin. Is 5 to 20 mPa · s, and the viscosity of the composition obtained by dissolving or dispersing gold in an organic resin is 10 to 20 mPa · s.

The conductor content of the composition is preferably 30 to 70 wt%, preferably 40 to 60 wt%. Since the solvent of the composition is dried to form the first pattern, the conductor content of the first pattern is higher than the conductor content of the composition.

The diameter of the metal particles depends on the diameter of each nozzle, the desired pattern shape, etc., but it is preferably as small as possible, preferably 0.1 μm or less, in order to prevent nozzle clogging and to produce a high-definition pattern. Is preferable. The metal particles are formed by a known method such as an electrolysis method, an atomizing method or a wet reduction method, and the particle size thereof is generally about 0.5 nm to 10 μm. However, when formed by the in-gas evaporation method, the nanoparticles protected by the dispersant are as fine as about 7 nm. Further, when the surface of each particle is covered with a coating agent, the nanoparticles do not aggregate in the solvent, are stably dispersed at room temperature, and exhibit almost the same behavior as a liquid.

The step of discharging the composition may be performed under reduced pressure. This is because the organic resin of the composition volatilizes before the composition is discharged and landed on the object to be processed, and the energy density of the laser beam can be weakened in the step of firing the metal particles. is there.

Next, the laser beam 103 is irradiated to the first pattern 102 using the laser beam direct drawing apparatus. Here, the laser beam is moved in the direction indicated by the arrow 104. By this step, the organic resin in the composition in the region irradiated with the laser beam is volatilized and removed. Further, the fusion of the metal particles proceeds by the energy of the laser beam, and the first conductive layer 105 as shown in FIG. 1 (B) is formed.

Since the laser beam is applied to the first pattern to volatilize and remove the organic resin in the first pattern, the conductor content of the first conductive layer 105 is higher than the conductor content of the first pattern. ..

When the metal particles are composed of a plurality of metal elements, the first conductive layer has a composition similar to that of the metal particles. When the energy of the irradiated laser beam is high, the first conductive layer can be an alloy having a composition different from that of the metal particles. However, even in this case, the metal element contained in the first conductive layer is the same as that of the metal particles.

The region not irradiated with the laser beam 103 remains as the first pattern. The first pattern remaining on both side surfaces of the first conductive layer is referred to as the first organic resin layer 106. Here, the first organic resin layer 106 is provided on both side surfaces of the first conductive layer, but the present invention is not limited to this, and the first organic resin layer 106 is provided only on one side surface of the first conductive layer. It may be provided. The first organic resin layer has conductivity or insulation depending on the dispersion ratio of the metal particles. The atmosphere at the time of irradiation of the laser beam is an oxygen atmosphere, a nitrogen atmosphere or air. However, it is preferable to carry out the operation in an oxygen atmosphere in which the organic resin in which the metal particles are dissolved or dispersed is easily removed.

Here, the laser beam direct drawing apparatus will be described with reference to FIG. As shown in the figure, the laser beam drawing apparatus 1001 includes a personal computer (hereinafter referred to as a PC) 1002 that executes various controls when irradiating a laser beam, a laser oscillator 1003 that outputs a laser beam, and a laser oscillator. Power supply 1004 of 1003, optical system (ND filter) 1005 for attenuating the laser beam, acousto-optic modulator (AOM) 1006 for modulating the intensity of the laser beam, and enlargement or reduction of the cross section of the laser beam. An optical system 1007 consisting of a lens for switching, a mirror for changing the optical path, a substrate moving mechanism 1009 having an X stage and a Y stage, and a D / A for digital-analog conversion of control data output from a PC. It is equipped with a conversion unit 1010, a driver 1011 that controls the acousto-optic modulator 1006 according to the analog voltage output from the D / A conversion unit, and a driver 1012 that outputs a drive signal for driving the board moving mechanism 1009. ing.

As the laser oscillator 1003, a laser oscillator capable of oscillating ultraviolet light, visible light, or infrared light can be used. Laser oscillators include excimer laser oscillators such as KrF, ArF, XeCl, and Xe, gas laser oscillators such as He, He-Cd, Ar, He-Ne, and HF, and YAG and YVO.₄, YLF, YAlO₃A solid-state laser oscillator using a crystal doped with Cr, Nd, Er, Ho, Ce, Co, Ti or Tm, or a semiconductor laser oscillator such as GaN, GaAs, GaAlAs, InGaAsP can be used. In the solid-state laser oscillator, it is preferable to apply the second harmonic to the fifth harmonic of the fundamental wave.

Next, a laser beam irradiation method using a laser beam direct drawing device will be described. When the board 1008 is mounted on the board moving mechanism 1009, the PC 1002 detects the position of the marker attached to the board by a camera (not shown). Next, the PC1002 generates movement data for moving the substrate movement mechanism 1009 based on the detected marker position data and the drawing pattern data input in advance. After that, the PC1002 controls the output light amount of the acousto-optic modulator 1006 via the driver 1011, so that the laser beam output from the laser oscillator 1003 is attenuated by the optical system 1005, and then the acousto-optic modulator 1006 The amount of light is controlled so that the amount of light becomes a predetermined amount. On the other hand, the laser beam output from the acousto-optic modulator 1006 changes the optical path and beam shape by the optical system 1007, is focused by a lens, and then irradiates the composition (first pattern) on the substrate with the beam. Then, the metal particles in the composition are fired. At this time, the substrate moving mechanism 1009 is moved and controlled in the X and Y directions according to the movement data generated by the PC 1002. As a result, the laser beam is irradiated to a predetermined place, and the metal particles in the composition are fired.

Here, the laser beam is moved in the XY axis direction to irradiate the laser beam. In this case, it is preferable to use a polygon mirror or a galvano mirror for the optical system 1007.

Here, a composition containing Ag (hereinafter referred to as Ag paste) is selectively discharged, a part of the Ag paste is irradiated with a laser beam as shown above, and Ag particles are appropriately fired to form a film. A first conductive layer 105 having a thickness of 600 to 800 nm is formed. Here, the region irradiated with the laser beam becomes the first conductive layer. Therefore, when the laser beam is scanned once, the width of the first conductive layer is approximately the width of the beam spot. Therefore, in order to form the first conductive layer having a finer width, it is preferable to irradiate a laser beam having a lower wavelength. In this embodiment, laser light having a wavelength of either ultraviolet light or infrared light is used. As a result, the width of the beam spot can be narrowed. Further, the first conductive layer 105 functions as a gate electrode. Therefore, it is possible to form a semiconductor element having a short channel structure by irradiating the laser beam 103 having a narrow beam spot width with the first pattern 102. The width of the first conductive layer at this time is preferably 0.3 to 1 μm, preferably 0.5 to 0.8 μm. As a result, a semiconductor device having a short channel structure can be formed. Further, on both side surfaces of the first conductive layer 105, an organic resin layer 106 in which metal particles are dispersed is formed.

In the present embodiment, an example of irradiating the first pattern with laser light to form a conductive layer has been shown, but a semiconductor layer or an insulating layer can be appropriately formed instead of the conductive layer. .. In this case, a semiconductor material or an insulating material may be appropriately used for the first pattern.

Next, as shown in FIG. 1C, the first pattern 102 is irradiated with the laser beam 111 so as to overlap a part of the first conductive layer 105. Here, the laser beam 111 is moved in the direction of the arrow 112. Here, in order to form the gate wiring, it is preferable to irradiate the laser beam 111 having a beam width wider than that of the laser beam 103. As a result, as shown in FIG. 1 (D), the second conductive layer 113 is formed. The second conductive layer 113 is a conductive layer in which metal particles are fired, and a second organic resin layer 114 in which the metal particles are dispersed is formed on both side surfaces thereof. The second organic resin layer may be provided only on one side surface of the second conductive layer.

The top view of the substrate at this time is shown in FIG. A first organic resin layer 106 in which metal particles are dispersed is formed on both side surfaces of the first conductive layer 105 that functions as a gate electrode. Further, a second organic resin layer 114 in which metal particles are dispersed is formed on both side surfaces of the second conductive layer 113 that functions as a gate wiring. Further, the first conductive layer 105 and the second conductive layer 113 are connected to each other.

Here, the cross-sectional shape of the first conductive layer 105 will be described with reference to FIG.

FIG. 3A is an enlarged view of a cross section of the first conductive layer 105 perpendicular to the scanning direction of the laser beam (arrow 104 in FIG. 1A). An organic resin layer 106a in which metal particles are dispersed is formed on both side surfaces of the first conductive layer 105a. The cross-sectional shape of the first conductive layer 105a is a substantially right-angled quadrangle. That is, in the first conductive layer, the width of the upper surface and the width of the surface in contact with the substrate are substantially the same.

FIG. 3 (B) is an enlarged view of a cross section similar to that of FIG. 3 (A). An organic resin layer 106b in which metal particles are dispersed is formed on both side surfaces of the first conductive layer 105b. The cross-sectional shape of the first conductive layer 105b is approximately trapezoidal, and the width of the surface of the first conductive layer in contact with the substrate is narrower than the width of the upper surface of the first conductive layer. This shape is obtained when the energy intensity of the laser beam has a Gaussian shape and the energy distribution of the laser beam is convex with respect to the substrate.

FIG. 3 (C) is an enlarged view of a cross section similar to that of FIG. 3 (A). An organic resin layer 106c in which metal particles are dispersed is formed on both side surfaces of the first conductive layer 105c. The cross-sectional shape of the first conductive layer 105c is approximately trapezoidal, and the width of the surface of the first conductive layer in contact with the substrate is wider than the width of the upper surface of the first conductive layer. When the thermal conductivity of the substrate 101 is high, the energy of the irradiated laser beam is conducted in the lateral direction (direction along the substrate surface), and the width of the conductive layer on the substrate 101 side becomes wide, resulting in such a shape. ..

In FIG. 3, the first conductive layers 105a to 105c have a conductive layer formed up to the surface of the substrate, but the structure is not limited to this, and metal particles are formed between the first conductive layer and the substrate 101. An organic resin layer in which is dispersed may be provided.

Next, in FIG. 3A, the state of the calcined metal particles and the dispersed metal particles will be described with reference to FIG. 31. In the first conductive layer 105a irradiated with the laser beam, large metal particles 151 obtained by firing a plurality of metal particles are aggregated. Therefore, the proportion of the organic resin in the first conductive layer is small. On the other hand, in the organic resin layer 106a in which the metal particles are dispersed, a large number of metal particles 153 are dispersed in the organic resin 152. Therefore, the proportion of the organic resin in the organic resin layer is higher than the proportion of the organic resin in the first conductive layer.

By the above steps, it is possible to form a wiring having a film pattern having a fine width.

(Embodiment 2) In this embodiment, a method for manufacturing a semiconductor device will be described with reference to FIG. In the present embodiment, a channel-etched TFT of a bottom gate TFT will be used as the semiconductor element.

As shown in FIG. 4A, the first pattern 202 is formed on the substrate 201 by the droplet ejection method. As the material of the first pattern 202, the material of the first pattern 102 shown in the first embodiment can be appropriately used.

In the present embodiment, the first pattern 202 selectively ejects an Ag paste in which silver particles of several nm are dispersed.

Next, a laser beam direct drawing apparatus is used to irradiate a part of the first pattern 202 with the laser beam 203 to form the first conductive layer 211 as shown in FIG. 4 (B). At this time, the region not irradiated with the laser beam 203 remains as the Ag paste. Hereinafter, the region remaining as the Ag paste is referred to as an organic resin layer 212 in which metal particles are dispersed. The first conductive layer 211 is formed by irregularly overlapping fine particles, which are conductors, in three dimensions. That is, it is composed of three-dimensional aggregate particles. Therefore, the surface has fine irregularities. Further, depending on the heating temperature and heating time of the Ag paste, the fine particles are melted to form an aggregate of the fine particles. Since the size of the aggregate at this time increases with the heating temperature and heating time of the Ag paste, the conductive layer has a large difference in surface height. The region where the fine particles are melted may have a polycrystalline structure. The width of the first conductive layer 211 depends on the laser beam diameter. Therefore, by irradiating the first pattern with a laser beam having a small beam diameter, a first conductive layer having a narrow width can be formed. Since the first conductive layer functions as a later gate electrode, a TFT having a short channel structure can be formed.

At this time, the multi-gate electrode can be formed by irradiating the first pattern with a plurality of laser beams so as not to overlap. Therefore, a TFT having a multi-gate structure can be formed later. At this time, it is preferable to irradiate the plurality of laser beams so that they are parallel to each other.

Next, as shown in FIG. 4C, a first insulating layer 221, a first semiconductor film, which functions as a gate insulating film on the first conductive layer 211 and the organic resin layer 212 in which metal particles are dispersed. 222, a second conductive film 223 is formed. Here, it is preferable to form the film after the first insulating layer 221 at a temperature lower than the temperature at which the organic resin contained in the composition used as the material of the first pattern 202 reacts. When the film after the first insulating layer 221 is formed at a temperature higher than the reaction temperature of the organic resin, the organic resin reacts and releases gas. Due to this gas, film peeling occurs, and the yield of the semiconductor element and the semiconductor device having the semiconductor element decreases. Therefore, it is possible to improve the yield by forming a film at a temperature lower than the reaction temperature of the organic resin.

The first insulating layer 221 is formed of a single layer or a laminated structure of an insulating film containing silicon nitride, silicon oxide, or other silicon by using a thin film forming method such as a plasma CVD method or a sputtering method. Further, it is preferable that the first insulating layer has a laminated structure of a silicon nitride film (silicon oxide film), a silicon oxide film, and a silicon nitride film (silicon oxide film) from the side in contact with the gate electrode. In this structure, since the gate electrode is in contact with the silicon nitride film, deterioration due to oxidation can be prevented.

The first semiconductor film 222 includes an amorphous semiconductor (AS), a semi-amorphous semiconductor (also referred to as SAS) in which an amorphous state and a crystalline state are mixed, and a crystal having a diameter of 0.5 nm to 20 nm in the amorphous semiconductor. It is formed of a film having either a state selected from a microcrystalline semiconductor in which grains can be observed and a crystalline semiconductor. In particular, a microcrystal state in which crystals of 0.5 nm to 20 nm can be observed is called a so-called microcrystal (μc). In each case, a semiconductor film having a film thickness of 10 to 60 nm, which is mainly composed of silicon, silicon-germanium (SiGe), or the like, can be used.

SAS is a semiconductor that has an intermediate structure between an amorphous structure and a crystal structure (including single crystal and polycrystal) and has a third state that is stable in free energy. It also contains a crystalline region with short-range order and lattice strain. A crystal region of 0.5 to 20 nm can be observed in at least a part of the membrane, and the Raman spectrum is 520 cm when silicon is the main component.^-1It is shifting to the low wavenumber side. In X-ray diffraction, diffraction peaks (111) and (220), which are said to be derived from the silicon crystal lattice, are observed. Also, in order to terminate unbonded hands (dangling bonds), SAS contains 1 atomic% or more of hydrogen or halogen.

SAS can obtain a silicified gas by a glow discharge decomposition method. As a typical silicified gas, SiH₄And also Si₂H₆, SiH₂Cl₂, SiHCl₃, SiCl₄, SiF₄Etc. can be used. The formation of SAS is facilitated by diluting the silicate gas with hydrogen or fluorine, or hydrogen or fluorine with one or more rare gas elements selected from helium, argon, krypton, and neon. be able to. At this time, it is preferable to dilute the siliceous gas so that the dilution ratio is in the range of 10 times to 1000 times. Also Si₂H₆And GeF₄Can be used to form SAS using the method of diluting with helium gas. The reaction formation of the coating film by the glow discharge decomposition method is preferably carried out under reduced pressure, and the pressure may be generally in the range of 0.1 Pa to 133 Pa. The electric power for forming the glow discharge may be a high frequency electric power of 1 MHz to 120 MHz, preferably 13 MHz to 60 MHz. The substrate temperature is preferably 300 degrees or less, and a substrate temperature of 100 to 250 degrees is recommended.

Further, the crystalline semiconductor film can be formed by crystallizing an amorphous semiconductor film or SAS by heating or laser irradiation. Moreover, you may directly form a crystalline semiconductor film. In this case, GeF₄, Or F₂Fluorine-based gas such as SiH₄, Or Si₂H₆A crystalline semiconductor film can be directly formed by using heat or plasma with a silane-based gas such as the above.

The second semiconductor film 223 has conductivity. When forming an n-channel TFT, elements of the 15 genera, typically phosphorus or arsenic, are added. When forming a p-channel TFT, elements of the 13 genera, typically boron, are added. The second semiconductor film is formed by a plasma CVD method in which a gas having elements of groups 13 or 15 such as boron, phosphorus, and arsenic is added to a siliceous gas. Further, after the semiconductor film is formed, a solution having elements of the 13th or 15th group can be applied onto the semiconductor film and irradiated with a laser beam to form a second conductive semiconductor film. As the laser beam, a known pulse-oscillated laser or a laser beam emitted from a continuously-oscillated laser is appropriately used.

Next, the first mask pattern 224 is formed on the second semiconductor film 223. The first mask pattern is preferably formed using a heat-resistant polymer material, and is a polymer having an aromatic ring or a heterocycle as a main chain, having few aliphatic portions, and containing a highly polar heteroatom group. It is preferably formed by ejecting droplets. Typical examples of such polymer substances include polyimide and polybenzimidazole. When polyimide is used, a solution containing polyimide can be discharged from a discharge port onto the second semiconductor film 223 and fired at 200 ° C. for 30 minutes to form the polyimide.

Next, the second semiconductor film 223 is etched using the first mask pattern 224 to form the second semiconductor region 232 shown in FIG. 4 (D). Next, the first semiconductor film 222 is etched with the first mask pattern 224 to form the first semiconductor region 231. After this, the first mask pattern is removed.

The first semiconductor film and the second semiconductor film are Cl.₂, BCl₃, SiCl₄Or CCl₄Chlorine-based gas represented by, CF₄,SCIENCE FICTION₆, NF₃, CHF₃Fluorine-based gas represented by, or O₂Can be etched using.

Next, the second patterns 251, 252 functioning as the source electrode and the drain electrode are formed on the second semiconductor region 232 using the conductive material. Here, the solution Ag paste in which silver particles of several nm are dispersed is selectively discharged. Next, using a laser beam direct drawing device, a part of the second patterns 251, 252 is irradiated with laser light to form the second conductive layers 261, 262 as shown in FIG. 4 (F). .. The second conductive layer is a conductive layer in which metal particles are fired, like the first conductive layer. Organic resin layers in which metal particles are dispersed may be formed on both side surfaces of the second conductive layer.

Next, using the second conductive layers 261 and 262 as masks, the exposed portion of the second semiconductor region 232 is etched and divided to form the source region and the drain regions 254 and 255. At this time, a part of the exposed portion of the first semiconductor region 231 may be etched.

When the first semiconductor region is formed of SAS, in addition to the structure in which the source region and the drain region cover the gate electrode as in the present embodiment, the ends and the gate of the source region and the drain region are used. It can be a so-called self-aligned structure in which the ends of the electrodes are aligned. Further, the structure may be such that the source region and the drain region do not cover the gate electrode and are formed at a certain distance. In the case of this structure, since the off-current can be reduced, the contrast can be improved when the TFT having the configuration is used as the switching element of the display device. Further, a TFT having a so-called multi-gate structure in which the second semiconductor region covers a plurality of gate electrodes may be used. In this case as well, the off-current can be reduced.

Next, it is preferable to form a passivation film on the second conductive layers 261 and 262. The passivation film uses a thin film forming method such as a plasma CVD method or a sputtering method, and uses silicon nitride, silicon oxide, silicon nitride oxide, silicon nitride nitride, aluminum nitride oxide, or aluminum oxide, diamond-like carbon (DLC), and nitrogen-containing carbon. It can be formed using (CN) or other insulating material.

Through the above steps, a channel-etched TFT having a narrow gate electrode width can be manufactured. Since the semiconductor element has a short channel length, it can operate at high speed.

(Embodiment 3) In the present embodiment, a channel-protected TFT will be described with reference to FIG. 5 in a bottom gate TFT as a semiconductor element.

As shown in FIG. 5 (A), the first conductive layer 211 that functions as a gate electrode on the substrate 201 and the organic resin in which metal particles provided on both side surfaces thereof are dispersed by the same process as in the second embodiment. After forming the layer 212, the first insulating layer 221 and the first semiconductor film 222 that function as the gate insulating film are formed. Next, the protective film 301 is formed on the first semiconductor film 222 and in the region superimposing on the first conductive layer 211. As the method and material for forming the protective film 301, the same method and material as those of the first mask pattern 224 shown in the second embodiment can be used.

Next, as shown in FIG. 5 (B), a second semiconductor film (conducting semiconductor film) 302 is formed. The second semiconductor film 302 can be formed by the same material and manufacturing method as the second semiconductor film 223 of the second embodiment. Next, the first mask pattern 224 is formed.

Next, using the first mask pattern, as shown in FIG. 5C, the second semiconductor film is etched to form the second semiconductor region 332. Further, the first semiconductor film is etched to form the first semiconductor region 231. After this, the first mask pattern is removed.

Next, as shown in FIG. 5 (D), the second conductive layer 341 is formed using the conductive material. As the conductive material, one or more selected from Ag, Au, Cu, Ni, Pt, Pd, Ir, Rh, W, Al, Ta, Mo, Cd, Zn, Fe, and Ti can be used. The second conductive layer 341 is formed by a known method such as a CVD method, a sputtering method, a printing method, or a droplet ejection method. Here, the second conductive layer 341 is formed by a sputtering method.

Next, the photosensitive resin 342 is discharged or applied onto the second conductive layer 341, and then dried. As the photosensitive resin, a material that is sensitive to ultraviolet light to infrared light, a negative type photosensitive resin, or a positive type photosensitive resin is used.

As the photosensitive resin, a resin material exhibiting photosensitivity such as epoxy resin, phenol resin, novolak resin, acrylic resin, melamine resin, and urethane resin is used. In addition, photosensitive organic materials such as benzocyclobutene, parylene, flare, and polyimide can be used. Typical positive-type photosensitive resins include novolak resins and phenol resins, and photosensitive resins having a naphthoquinone diazide compound as a photosensitizer. As negative-type photosensitive resins, the above-mentioned resins and the like are used as base resins. Examples thereof include a photosensitive resin having a diphenylsilanediol and an acid generator. In this embodiment, a negative photosensitive resin is used.

Next, the photosensitive resin 342 is irradiated with the laser beam 343 using a laser beam direct drawing device, and then developed. As a result, the second mask patterns 351, 352 are formed as shown in FIG. 5 (E).

Next, as shown in FIG. 5 (F), the second conductive layer 341 is etched with the second mask patterns 351 and 352 as masks to form the source electrode and the drain electrode 361 and 362. Further, the second semiconductor region 332 is etched using the second mask pattern as a mask to form the source region and the drain regions 363 and 364. By this step, the protective film 301 is exposed.

The method of forming the source electrode and the drain electrode is not limited to this embodiment, and the method shown in the second embodiment may be used. Further, the process of forming the source electrode and the drain electrode of the present embodiment may be applied to the second embodiment.

Through the above steps, a channel-protected TFT having a narrow gate electrode width can be manufactured. Since the semiconductor element has a short channel length, it can operate at high speed.

(Embodiment 4) In the present embodiment, a method for producing a forward staggered TFT among the top gate TFTs will be described with reference to FIG.

As shown in FIG. 6A, the first patterns 401 and 402 are formed on the substrate 201. As the material and the manufacturing method, the same material and the same as the first pattern 102 of the first embodiment can be appropriately used. Next, the first patterns 401 and 402 are irradiated with the laser beam 403. Here, the laser beam is irradiated in the direction of arrow 404 to form the first conductive layers 411 and 412 in which the metal particles are fired, as shown in FIG. 6 (B).

Next, a conductive first semiconductor film 413 is formed on the first conductive layer. The first semiconductor film 413 can be manufactured by the same material and manufacturing method as the second semiconductor film 222 shown in the second embodiment. Next, the first mask patterns 414 and 415 are formed on the first semiconductor film 413. The first mask pattern can be produced by appropriately using the same materials and production methods as those of the first mask pattern 224 shown in the second embodiment.

Next, as shown in FIG. 6C, the first semiconductor film is etched using the first mask pattern to form the first semiconductor regions 416 and 417. The first semiconductor region functions as a source region and a drain region. Next, a second semiconductor film 421 is formed. The second semiconductor film 421 can be manufactured by appropriately using the same materials and methods as those of the first semiconductor film 222 shown in the second embodiment.

Next, a part of the surface of the second semiconductor film 421 is irradiated with a laser beam using a laser beam direct drawing device to form a silicon oxide film 431 as shown in FIG. 6 (D). The silicon oxide film 431 functions as a mask for etching the second semiconductor film 421. Next, the exposed portion of the second semiconductor film is etched with TMAH (tetramethylammonium hydroxide) to form the second semiconductor region 441 as shown in FIG. 6 (E). Here, by irradiating the second semiconductor film with laser light using a laser beam direct drawing apparatus, it is possible to oxidize an arbitrary region and form a silicon oxide film. Therefore, it is possible to form a semiconductor region at a predetermined location without using a known photolithography process. Further, by reducing the spot diameter of the laser beam, the irradiation area of the laser beam can be narrowed. That is, it is possible to form a finely shaped silicon oxide film and a semiconductor region formed by using the silicon oxide film as a mask. Therefore, high integration of semiconductor elements is possible. Further, it is possible to improve the throughput by irradiating a laser beam having a shape of a semiconductor region (rectangular shape, circular shape, predetermined shape, etc.) at a time to form a silicon oxide film.

Next, as shown in FIG. 6 (E), a second pattern 442 is formed on the silicon oxide film 431. The silicon oxide film 431 functions as a gate insulating film. After removing the silicon oxide film 431, an insulating layer that functions as a gate insulating film may be newly formed by appropriately using the same method and material as the first insulating layer 221 of the second embodiment. Next, the second pattern 442 is irradiated with laser light 443, and as shown in FIG. 6 (F), the second conductive layer 451 in which the metal particles are fired and the organic resin layer 452 in which the metal particles are dispersed are dispersed. , 453 can be formed. The second conductive layer 451 functions as a gate electrode.

By the above steps, a forward staggered TFT can be produced.

(Embodiment 5) In this embodiment, a method for producing a coplanar type TFT among the top gate TFTs will be described with reference to FIG. 7.

As shown in FIG. 7A, a first insulating layer 501 is formed on the substrate 201. The first insulating layer 501 functions as a blocking film for preventing impurities from the substrate from diffusing into the semiconductor region formed later. Therefore, as the first insulating layer 501, a base film made of an insulating film such as a silicon oxide film, a silicon nitride film, or a silicon nitride film is formed. The base film is formed of a single-layer film or a structure in which two or more layers are laminated.

Next, the semiconductor film 502 is formed on the first insulating layer 501. The semiconductor film is formed by forming a semiconductor film having an amorphous structure by a known means (blasting method, LPCVD method, plasma CVD method, etc.) and then performing a known crystallization process (laser emitted from a pulse oscillation laser). A crystalline semiconductor film obtained by performing a laser crystallization method using light, a thermal crystallization method, or a thermal crystallization method using a metal catalyst such as nickel), or the SAS shown in the second embodiment. Film with AS or the like.

Next, the predetermined region of the semiconductor film 502 is irradiated with the laser beam 503 by the laser beam direct drawing apparatus as in the fourth embodiment to form the silicon oxide film 511 as shown in FIG. 7 (B). To do. Here, the laser beam 503 is scanned in the direction of arrow 504, and the region that later forms the semiconductor region is irradiated with the laser beam.

Next, the semiconductor film 502 is etched with TMAH using the silicon oxide film 511 as a mask to form the semiconductor region 512.

Next, as shown in FIG. 7C, after removing the silicon oxide film 511, a second insulating layer 521 functioning as a gate insulating film is formed on the semiconductor region 512 and the first insulating layer 501. .. The second insulating layer 521 can be formed by using the same material and manufacturing method as the first insulating layer 221 shown in the second embodiment.

Next, the first pattern 522 is formed. The first pattern is formed by using the same material as the first pattern 102 shown in the first embodiment. Next, a part of the first pattern 522 is irradiated with a laser beam 523, and the first conductive layer 531 in which the metal particles are fired as shown in FIG. 7 (D) and the organic resin in which the metal particles are dispersed are dispersed. Layer 532 can be formed. The first conductive layer 531 functions as a gate electrode.

Next, as shown in FIG. 7 (E), impurities are added to the semiconductor region 512 using the first conductive layer 531 and the organic resin layer 532 in which the metal particles are dispersed as a mask. Next, after forming an insulating film containing hydrogen, it is heated to 400 to 550 degrees to activate the impurity elements added to the semiconductor region, and hydrogenation of the semiconductor region is performed to perform the impurity region (source region and Drain area) 541, 542 are formed. Further, the semiconductor region covered with the first conductive layer 531 and the organic resin layer 532 in which the metal particles are dispersed functions as the channel forming region 543. As the activation or hydrogenation step, the GRTA method, the LRTA method, or the laser annealing method can be used instead of the heat treatment. In addition, when the semiconductor film is crystallized using a metal element that promotes crystallization, typically nickel, gettering can be performed at the same time as activation.

In the present embodiment, the TFT having a single gate structure is shown, but the TFT is not limited to this and may have a multi-gate structure. Moreover, although the TFT of the self-aligned structure is shown, the TFT of the low concentration drain (LDD: Lightly Doped Drain) structure or the GOLD (Gate-drain Overlapped LDD) structure can be used. The LDD structure is formed by providing a region in which an impurity element is added at a low concentration between a channel forming region and a source region or a drain region formed by adding an impurity element in a high concentration, and this region is an LDD region. I call it. The TFT of this structure can reduce the off-current value. The GOLD structure is a structure in which the LDD region is superposed on the gate electrode via a gate insulating film, and has the effect of relaxing the electric field near the drain and preventing deterioration due to hot carrier injection.

Further, the organic resin layer 532 in which the metal particles are dispersed may be used as a sidewall to add an impurity element to the semiconductor region to form an LDD region.

Next, a third insulating layer 544 is formed on the substrate. As the material of the third insulating layer, silicon oxide, silicon nitride, silicon oxide nitride, aluminum oxide, aluminum nitride, aluminum oxynitride and other inorganic insulating materials, acrylic acid, methacrylic acid and derivatives thereof, or polyimide ( Inorganic siloxane material containing Si-O-Si bonds formed from a heat-resistant polymer such as polymer), aromatic polyamide, polybenzimidazole, or a siloxane polymer-based material typified by silica glass as a starting material. Hydrogen bonded to silicon represented by alkylsiloxane polymer, alkylsilsesquioxane polymer, hydride silsesquioxane polymer, hydride alkylsilsesquioxane polymer was replaced by an organic group such as methyl or phenyl. An organic siloxane polymer-based insulating material can be used. As a forming method, a known method such as a CVD method, a coating method, or a printing method is used for forming. By forming by the coating method, the surface of the second insulating layer can be flattened, which is suitable for later formation of the pixel electrode. Here, an alkylsiloxane polymer is applied and fired by a coating method to form a third insulating layer 544.

Next, a mask pattern is formed by the droplet ejection method, and a part of the second insulating layer 544 and the second insulating layer 521 is removed by using the mask pattern to form the impurity regions 541 and 542 in the semiconductor region. Part of it is exposed to form an opening. Next, the second conductive layers 545 and 546 are formed in the opening by appropriately using the method described in the second embodiment or the third embodiment. The second conductive layers 545 and 546 function as source electrodes and drain electrodes.

By the above steps, a coplanar type TFT having a narrow gate electrode width can be manufactured. Since the semiconductor element has a short channel length, it can operate at high speed.

(Embodiment 6) In this embodiment, the manufacturing process of the organic semiconductor transistor will be described with reference to FIG.

As shown in FIGS. 8A and 8B, after forming the first pattern 202 on the substrate 201 as in the second embodiment, the laser beam 203 is applied to a part of the first pattern 202. By irradiating, the first conductive layer 211 in which the metal particles are fired and the organic resin layer 212 in which the metal particles provided on both side surfaces thereof are dispersed are formed. Here, plastic is used for the substrate 201.

Next, as shown in FIG. 8C, a first insulating layer 601 that functions as a gate insulating film is formed on the substrate 201, the first conductive layer 211, and the organic resin layer 212. As the first insulating layer, the material and method of the first insulating layer 221 shown in the second embodiment can be appropriately used. Further, it can be formed by applying an insulating solution by using a droplet ejection method, a coating method, or the like. Further, the first conductive layer 211 may be anodized to form the first insulating layer. Typical examples of insulating solutions include solutions in which fine particles of inorganic oxide are dispersed, polyimide, polyamide, polyester, acrylic, PSG (phosphorus glass), BPSG (phosphorus glass), and silicate-based SOG (Spin on Glass). ), Acrylic silicate-based SOG, siloxane polymer and the like can be appropriately used. At this time, the insulating solution is dried and fired depending on the material.

Next, the second conductive layer 602 is formed. Here, it can be formed by the same method and material as the second conductive layer 341 of the third embodiment. Next, the first mask patterns 603 and 604 are formed on the second conductive layer 602. The mask pattern is formed by using the same material as the first mask pattern 224 of the second embodiment. The first mask patterns 603 and 604 are mask patterns for forming the source electrode and the drain electrode later.

Next, as shown in FIG. 8D, the second conductive layer 602 is etched using the first mask patterns 603 and 604 to form the third conductive layers 611 and 612. The third conductive layers 611 and 612 function as source electrodes and drain electrodes. Next, a semiconductor region 613 is formed between the source electrode and the drain electrode using an organic semiconductor material.

As a method for forming the semiconductor region 613, a printing method, a spray method, a droplet ejection method, or the like can be appropriately used. Since this method does not require an etching process, it is possible to reduce the number of processes. Further, as the organic semiconductor material, a known organic semiconductor material can be appropriately used. As a typical example, a π-electron conjugated polymer material whose skeleton is composed of a conjugated double bond is desirable. Typically, soluble polymer materials such as polythiophene, poly (3-alkylthiophene), polythiophene derivatives, and pentacene can be used.

In addition, a semiconductor region can be formed by forming a soluble precursor and then treating it. Examples of the organic semiconductor material via such a precursor include polythienylene vinylene, poly (2,5-thienylene vinylene), polyacetylene, a polyacetylene derivative, and polyarylene vinylene.

When converting a precursor into an organic semiconductor, not only heat treatment but also a reaction catalyst such as hydrogen chloride gas is added. Typical solvents for dissolving these soluble organic semiconductor materials include toluene, xylene, chlorobenzene, dichlorobenzene, anisole, chloroform, dichloromethane, γ-butyllactone, butyl cellsolve, cyclohexane, and NMP (N-methyl-). 2-pyrrolidone), cyclohexanone, 2-butanone, dioxane, dimethylformamide (DMF), THF (tetrahydrofuran) and the like can be applied.

Further, a contact layer may be provided between the semiconductor region 613 and the conductive layers 611 and 612 that function as source electrodes and drain electrodes. As the material of the contact layer, a conductive layer formed of an organic conductive material such as polyacetylene, polyaniline, PEDOT (poly-ethylenedioxythiophen), and PSS (poly-styrene sulphonate) can be formed. Further, a conductive layer formed of a metal element can be used as the contact layer. In this case, since many organic semiconductor materials are p-type semiconductors that transport holes as carriers, it is desirable to use a metal having a large work function in order to make ohmic contact with the semiconductor layer. Typically, metals or alloys such as gold, platinum, chromium, palladium, aluminum, indium, molybdenum, and nickel are desirable. It can be formed by a printing method or a droplet ejection method using a conductive paste using these metal or alloy materials.

By the above steps, an organic thin film transistor having a short channel structure can be formed.

(Embodiment 7) In the present embodiment, a method of manufacturing a semiconductor element having a different positional relationship between the source electrode and the drain electrode and the semiconductor region in the sixth embodiment will be described with reference to FIG.

As shown in FIGS. 9A and 9B, after forming the first pattern 202 on the substrate 201 as in the second embodiment, the laser beam 203 is applied to a part of the first pattern 202. Irradiate. Next, the first conductive layer 211 in which the metal particles are fired and the organic resin layer 212 in which the metal particles provided on both side surfaces thereof are dispersed are formed.

Next, as shown in FIG. 9C, a first insulating layer 601 that functions as a gate insulating film is formed on the substrate 201, the first conductive layer 211, and the organic resin layer 212. Next, the semiconductor region 701 is formed on the first insulating layer 601. As the material and the forming method of the semiconductor region 701, the material and the method described in the sixth embodiment are appropriately used.

Next, as shown in FIG. 9D, a third conductive layer 711 is formed on the first insulating layer 601 and the semiconductor region 701. Next, the first mask patterns 712 and 713 are formed on the second conductive layer 711. As the second conductive layer 711 and the first mask patterns 712 and 713, the second conductive layer 602 and the first mask patterns 603 and 604 shown in the sixth embodiment can be appropriately used, respectively. The first mask pattern functions as a mask for forming the source electrode and the drain electrode to be formed later.

Next, as shown in FIG. 9 (E), the second conductive layer 711 is etched using the first mask patterns 712 and 713 to form the source electrode and the drain electrode 721 and 722. The semiconductor element manufactured in the present embodiment has a region in which the semiconductor region 701 is sandwiched between the first insulating layer 601 that functions as a gate insulating film and one of the source electrode and the drain electrodes 721 and 722.

By the above steps, an organic thin film transistor having a short channel structure can be formed.

(Embodiment 8) In this embodiment, the droplet ejection device that can be used for forming the mask pattern in the above embodiment will be described. In FIG. 10, the region on which one panel 1930 is formed is shown by a dotted line on the substrate 1900.

FIG. 10 shows an aspect of a droplet ejection device used for forming a pattern such as wiring. The droplet ejection means 1905 has a head, and the head has a plurality of nozzles. In the present embodiment, the case where three heads (1903a, 1903b, 1903c) provided with ten nozzles are provided will be described, but the number of nozzles and the number of heads should be set according to the processing area, process, and the like. Can be done.

The head is connected to the control means 1907, and the control means can be controlled by the computer 1910 to draw a preset pattern. The drawing timing may be performed, for example, with the marker 1911 formed on the substrate 1900 or the like fixed on the stage 1931 as a reference point. Further, the edge of the substrate 1900 may be used as a reference point. These reference points are detected by an imaging means 1904 such as a CCD, and converted into a digital signal by an image processing means 1909. The computer 1910 recognizes the digitally converted signal, generates a control signal, and sends it to the control means 1907. When drawing the pattern in this way, the distance between the pattern forming surface and the tip of the nozzle is preferably 0.1 cm to 5 cm, preferably 0.1 cm to 2 cm, and more preferably around 0.1 cm. By shortening the interval in this way, the landing accuracy of the droplet is improved.

At this time, the information of the pattern formed on the substrate 1900 is stored in the storage medium 1908, and based on this information, a control signal can be sent to the control means 1907 to individually control each head 1903a to 1903c. it can. That is, droplets having different compositions can be ejected from the nozzles of the heads 1903a to 1903c. For example, the nozzles of the heads 1903a and 1903b can eject droplets of the composition forming the insulating film, and the nozzles of the head 1903c can eject the droplets of the composition forming the conductive film.

Further, each nozzle of the head can be controlled individually. Since the nozzles can be controlled individually, droplets of different compositions can be ejected from a specific nozzle. For example, the same head 1903a may be provided with a nozzle for ejecting a droplet of a composition forming a conductive film and a nozzle for ejecting a droplet of a composition forming an insulating film.

The nozzle is connected to a tank filled with the composition.

Further, when the droplet ejection process is performed on a large area as in the step of forming the interlayer insulating film, it is preferable to eject the droplets of the composition forming the interlayer insulating film from all the nozzles. Further, it is preferable to eject the droplets of the composition forming the interlayer insulating film from all the nozzles of the plurality of heads. As a result, the throughput can be improved. Of course, in the interlayer insulating film forming step, droplets of the composition forming the interlayer insulating film may be ejected from one nozzle, and the droplet ejection treatment may be performed on a large area by scanning a plurality of droplets.

Then, the head can be zigzag or reciprocated to form a pattern on the large mother glass. At this time, the head and the substrate may be scanned relatively a plurality of times. When scanning the head with respect to the substrate, it is preferable to tilt the head diagonally with respect to the traveling direction.

When forming a plurality of panels from a large mother glass, the width of the head is preferably about the same as the width of one panel. This is because a pattern can be formed in a single scan on the area where one panel 1930 is formed, and high throughput can be expected.

Further, the width of the head may be smaller than the width of the panel. At this time, a plurality of heads having a small width may be arranged in series so as to have the same width as one panel. By arranging a plurality of heads having a small width in series, it is possible to prevent the occurrence of deflection of the head, which is a concern as the width of the head increases. Of course, the pattern may be formed by scanning the head having a small width a plurality of times.

Further, as the droplet ejection method, the piezo method can be used. The piezo method is also used in inkjet printers because it has excellent droplet controllability and a high degree of freedom in ink selection. The piezo method includes vendor type (typically MLP (Multi Layer Piezo) type), piston type (typically MLChip (Multi Layer Ceramic Hyper Integrated Piezo Segments) type), sidewall type, and roof. There is a wall type. Further, depending on the solvent of the solution, a droplet ejection method using a so-called thermal method, in which a heating element is generated to generate air bubbles to extrude the solution, may be used.

In this example, a sample in which a pattern is formed using Ag paste and the pattern is tentatively fired, and a sample in which a pattern is formed using Ag paste and the pattern is irradiated with laser light to burn Ag particles. The resistance value will be described with reference to FIG.

Table 1 shows the comparison results between the resistance value of the sample calcined under condition 1 and the resistance value of the sample calcined under condition 2 after dropping Ag paste onto the glass substrate by the droplet ejection method, and the graph is shown in the graph. Shown in 32. The shape of each sample whose resistance value was measured at this time is an ellipse with a major axis width D1 of 1000 μm and a minor axis width D2 of 200 μm, as shown in FIG. 32 (B). Condition 1 is a condition of heating at 100 degrees for 30 minutes. Condition 2 is YVO with continuous oscillation.₄Irradiate the laser light oscillated from the laser (laser power 2 W, laser beam diameter 80 μm, laser light wavelength 532 nm). The scanning speed at this time is 50 cm / sec.

<tables num="1"><img file="JP4536601B2_D0001.tif" /></tables>

As can be seen from Table 1 and FIG. 32, the resistance value of the sample is reduced by the treatment of condition 2. That is, by irradiating the paste containing the metal particles with a laser beam, the metal particles are fired and the resistance value can be reduced.

Next, a method of manufacturing the active matrix substrate and the display panel having the active matrix substrate will be described with reference to FIGS. 12 to 16. In this embodiment, a liquid crystal display panel will be used as the display panel. FIG. 16 is a top view of the active matrix substrate, and FIGS. 12 to 15 schematically show a vertical cross-sectional structure corresponding to AB of the connection terminal portion and CD of the pixel portion.

As shown in FIG. 12 (A), the surface of the substrate 800 is oxidized at 400 degrees to form an insulating film 801 having a film thickness of 100 nm. Next, the first conductive layer 802 is formed on the insulating film 801. A typical example of the first conductive layer 802 is a conductive film having a translucent property or a conductive film having a reflective property. Materials for the conductive conductive film having translucency include indium tin oxide (ITO), zinc oxide (ZnO), indium zinc oxide (IZO), zinc oxide with gallium added (GZO), indium tin oxide containing silicon oxide, etc. Can be mentioned. Further, as the material of the conductive film having reflectivity, a metal such as aluminum (Al), titanium (Ti), silver (Ag), tantalum (Ta), or a concentration equal to or less than the chemical quantitative composition ratio with the metal. Examples thereof include metal materials containing nitrogen, titanium nitride (TiN) and tantalum nitride (TaN), which are nitrides of the metal, and aluminum containing 1 to 20% nickel. Further, as a method for forming the first conductive layer 802, a sputtering method, a vapor deposition method, a CVD method, a coating method or the like is appropriately used. Here, an AN100 glass substrate manufactured by Asahi Glass Co., Ltd. is used as the substrate 800, and an indium tin oxide (ITO) containing silicon oxide having a film thickness of 110 nm is formed as the first conductive layer 802 by a sputtering method.

Next, the first mask pattern 803 is formed on the first conductive layer 802 by the droplet ejection method. The first mask pattern functions as a mask for forming a second mask pattern (a film that functions as a mask for etching the conductive layer) to be formed later. Therefore, it is preferable that the coating property is low. That is, it is preferable that the second mask pattern formed later is easy to play on the surface. Here, the first mask pattern is formed by using a solution of a fluorine-based silane coupling agent in an alcohol solvent.

Next, the second mask pattern 804 is formed by the droplet ejection method. The second mask pattern 804 ejects a highly wettable material by a droplet ejection method. The second mask pattern 804 is formed by ejecting polyimide by a droplet ejection method, heating it at 200 degrees for 30 minutes, and firing it.

Here, FIG. 30 is used to show the relationship between the region with low coatability and the region with high coatability. The region with low coatability (here, the first mask pattern 803) is a region on the surface where the contact angle θ1 of the liquid is large, as shown in FIG. On this surface, the liquid is repelled in a hemispherical shape. On the other hand, the highly wettable region (here, the second mask pattern 804) is a region on the surface where the contact angle θ2 of the liquid is small. On this surface, the liquid spreads.

Therefore, when two regions having different contact angles are in contact with each other, the region having a relatively small contact angle becomes a region having a high coating property, and the region having a large contact angle becomes a region having a low coating property. When the solution is applied or discharged on these two regions, the solution spreads on the surface of the region having low wettability and is hemispherically repelled at the interface with the region having high wettability.

The difference between the contact angle θ1 in the region with low wettability and the contact angle θ2 in the region with high wettability is preferably 30 degrees, preferably 40 degrees or more. As a result, the material of the region having high coating property is repelled by a hemisphere on the surface of the region having low coating property, and the mask patterns 803 and 804 can be formed in a self-aligned manner.

Next, as shown in FIG. 12B, after removing the first mask pattern 803 by ashing with oxygen, the first conductive layer 802 not covered by the second mask pattern 804 is etched. And remove it. Next, the second mask pattern 804 is removed to form the second conductive layer 805. The second conductive layer 805 functions as a pixel electrode.

Next, as shown in FIG. 12 (C), the first patterns 811 and 812 are formed. The third conductive layer is a metal particle such as Ag, Au, Cu, Ni, Pt, Pd, Ir, Rh, W, Al, Ta, Mo, Cd, Zn, Fe, Ti, Si, Ge, Zr, Ba. And the composition formed of the organic resin is ejected by a droplet ejection method to form the composition. Here, it is preferable to use a conductive material that does not easily form an oxide in contact with the second conductive layer 805.

Next, the first patterns 811 and 812 are partially irradiated with laser light 813 and 814 to form the third conductive layers 815 and 816 in which the metal particles as shown in FIG. 13 (A) are fired. .. At this time, the regions not irradiated with the laser beam in the first patterns 811 and 812 are the organic resin layers 817 and 818 in which the metal particles are dispersed. The third conductive layer 815 functions as the rear gate wiring, and the third conductive layer 816 functions as the rear gate electrode.

Next, the gate insulating film 821 is formed by a sputtering method. As the gate insulating film 821, a silicon nitride film (SiNO (N&gt; O)) having a film thickness of 110 nm is formed.

Next, a first semiconductor film 822 and a second semiconductor film 823 exhibiting n-type are formed. As the first semiconductor film 822, an amorphous silicon film having a film thickness of 150 nm is formed by a sputtering method. Next, after removing the oxide film on the surface of the amorphous silicon film, a semi-amorphous silicon film having a thickness of 50 nm is formed as the second semiconductor film 823 by the same method. Here, since the first semiconductor film and the second semiconductor film are formed by the sputtering method, the film can be formed at room temperature.

Next, the third mask patterns 824 and 825 are formed on the second semiconductor film. The third mask pattern is formed by ejecting polyimide onto the second semiconductor film by a droplet ejection method and heating at 200 ° C. for 30 minutes. The third mask patterns 824 and 825 are discharged onto the region where the first semiconductor region is formed later.

Next, as shown in FIG. 13 (B), the second semiconductor film 823 is etched using the third mask pattern to form the second semiconductor region (source region, drain region, contact layer) 826. .. The flow rate ratio of the second semiconductor film is CF₄: O₂Etching with a mixed gas of = 10: 9. After that, the third mask patterns 824 and 825 are peeled off using a peeling liquid.

Next, a fourth mask pattern 831 that covers the second semiconductor region 826 and the first semiconductor film 822 formed between them is formed. The fourth mask pattern is formed by the same materials and methods as the third mask pattern. Using the fourth mask pattern, the first semiconductor film 822 is etched to form the first semiconductor region 832 as shown in FIG. 13 (C) and a part of the gate insulating film 821 is exposed. The flow rate ratio of the first semiconductor film is CF₄: O₂After etching with a mixed gas of = 10: 9, ashing with oxygen is performed. After that, the fourth mask pattern 831 is peeled off using a peeling liquid.

Next, as shown in FIG. 14 (A), the fifth mask patterns 841 and 842 are formed. In the fifth mask pattern, a solution having low wettability is ejected to the region where the gate insulating film 821 and the second conductive layer 805 overlap and the connection terminal portion by the droplet ejection method. Here, as a solution having low coatability, a solution in which a fluorine-based silane coupling agent is dissolved in an alcohol solvent is used. The fifth mask patterns 841 and 842 are protective films for forming a sixth mask pattern used for forming a contact hole in the region where the subsequent drain electrode and the second conductive layer 805 are connected. The sixth mask pattern is also a protective film for exposing the conductive layer of the connection terminal portion.

Next, the sixth mask pattern 843 is formed. The sixth mask pattern is a mask for forming a contact hole, and is formed by ejecting polyimide by a droplet ejection method and heating at 200 ° C. for 30 minutes. At this time, since the fifth mask pattern 841 is formed of a material having a low coatability and the sixth mask pattern 843 is formed of a material having a high coatability, the region where the fifth mask pattern is formed. The sixth mask pattern 843 is not formed in.

Next, the fifth mask patterns 841 and 842 are removed by oxygen ashing to expose a part of the gate insulating film 821. Next, using the sixth mask pattern 843, a part of the exposed gate insulating film is etched to form the contact hole 844. The gate insulating film is CHF₃Etch using. After that, the sixth mask pattern is peeled off by oxygen ashing and etching with a peeling liquid.

Next, as shown in FIG. 14C, the fourth conductive layers 851 and 852 are formed by the droplet ejection method. The fourth conductive layer will be the source wiring layer and the drain wiring layer later. Here, the fourth conductive layers 851 and 852 discharge the composition in which Ag (silver) particles are dispersed, heat at 100 ° C. for 30 minutes to dry, and then irradiate the laser beam to fire the metal particles. To form.

By the above steps, an active matrix substrate can be formed. The planar structures corresponding to the vertical cross-sectional structures AB and CD in FIG. 14 (C) are shown in FIG. 16 and are referred to at the same time.

Next, as shown in FIG. 15 (A), the protective film 861 is formed. The protective film is a silicon target, and argon and nitrogen (flow rate ratio Ar: N) as sputtering gas.₂A silicon nitride film having a film thickness of 100 nm is formed by a sputtering method using = 1: 1).

Next, an insulating film is formed by a printing method or a spin coating method so as to cover the protective film 861, and rubbing is performed to form an alignment film 862. The alignment film 862 can also be formed by an orthorhombic vapor deposition method.

Next, in the facing substrate 881 provided with the alignment film 883 and the second pixel electrode (opposing electrode) 882, a closed loop-shaped sealing material 871 is formed in the region around the pixel portion by the droplet ejection method. The liquid crystal material is dropped inside the closed loop formed of the sealing material 871 by the dispenser type (dropping type).

A filler may be mixed in the sealing material 871, and a color filter, a shielding film (black matrix), or the like may be formed on the facing substrate 881.

Here, FIG. 17 shows a step of dropping the liquid crystal material. FIG. 17 (A) is a perspective view of a process of dropping the liquid crystal material by the dispenser 2701, and FIG. 17 (B) is a cross-sectional view taken along the line AB of FIG. 17 (A).

The liquid crystal material 2704 is dropped or discharged from the dispenser 2701 so as to cover the area 2703 surrounded by the sealing material 2702. The liquid crystal layer may be formed by moving the dispenser 2701 or fixing the dispenser 2701 and moving the substrate 2700. Further, a plurality of dispensers 2701 may be installed to drop the liquid crystal material into a plurality of regions at the same time. As a result, as shown in FIG. 17B, the liquid crystal material 2704 can be selectively dropped or discharged only in the region surrounded by the sealing material 2702.

Further, although the liquid crystal material is dropped on the pixel portion here, the substrate having the pixel portion may be bonded after dropping the liquid crystal material on the opposite substrate side.

Next, as shown in FIG. 15 (A), the facing substrate 881 provided with the alignment film 883 and the second pixel electrode (opposite electrode) 882 is bonded to the active matrix substrate in a vacuum, and UV curing is performed. This is done to form a liquid crystal layer 884 filled with a liquid crystal material. As a method for forming the liquid crystal layer 884, instead of the dispenser type (dropping type), a dip type (pumping type) in which the liquid crystal material is injected by using the capillary phenomenon after laminating the facing substrates can be used.

Next, as shown in FIG. 15 (B), when an insulating film is formed on each end of the third conductive layer 815 and the source wiring layer (not shown), after removing the insulating film, A connection terminal (a connection terminal 886 connected to the third conductive layer and a connection terminal connected to the source wiring layer are not shown) is attached via the connection conductive layer 885. Further, it is preferable to seal the connection portion between each wiring layer and the connection terminal with a sealing resin. With this structure, it is possible to prevent moisture from the cross-sectional portion from invading the pixel portion and deteriorating it. A liquid crystal display panel can be formed by the above steps.

A liquid crystal display panel can be manufactured by the above steps. A protection circuit for preventing electrostatic breakdown, typically a diode, or the like may be provided between the connection terminal and the source wiring (gate wiring) or in the pixel portion. In this case, electrostatic breakdown can be prevented by manufacturing in the same process as the above-mentioned TFT and connecting the gate wiring layer of the pixel portion and the drain or source wiring layer of the diode.

Any of the first to eighth embodiments can be applied to this embodiment.

In this embodiment, a method of manufacturing a light emitting display panel as a display panel will be described with reference to FIGS. 19 to 22. The planar structure of the pixel portion is shown in FIG. 22, and FIGS. 19 to 21 schematically show the vertical cross-sectional structure corresponding to AB and CD of the pixel portion of FIG. 22.

As shown in FIG. 19 (A), the first insulating layer 2002 is formed on the substrate 2001 with a film thickness of 100 to 1000 nm. Here, as the first insulating layer, a silicon oxide film having a film thickness of 100 nm using a plasma CVD method and a silicon oxide film having a film thickness of 480 nm using a reduced pressure thermal CVD method are laminated and formed.

Next, an amorphous semiconductor film is formed with a film thickness of 10 to 100 nm. Here, an amorphous silicon film having a film thickness of 50 nm is formed by using a reduced pressure thermal CVD method. Next, this amorphous semiconductor film is crystallized. In this embodiment, the amorphous silicon film is irradiated with laser light to form a crystalline silicon film. Next, unnecessary portions of the crystalline silicon film are removed to form semiconductor regions 2003 and 2004. Next, a second insulating layer 2005 that functions as a gate insulating film is formed. Here, a silicon oxide film is formed as the second insulating layer 2005 by the CVD method.

Next, a channel doping step of adding a p-type or n-type impurity element to a region to be a TFT channel region at a low concentration is performed on the entire surface or selectively. This channel doping step is a step for controlling the TFT threshold voltage. Here, diborane (B)₂H₆) Is plasma-excited without mass separation, and boron is added by the ion doping method. An ion implantation method for mass separation may be used.

Next, after forming the first patterns 2006 to 2009, the first conductive layers 2014 to 2016 that function as gate electrodes and the first conductive layers 2014 to 2016 that function as gate electrodes by irradiating the laser beams 2010 to 2013, and A first conductive layer 2017 that functions as a capacitive wiring is formed. At the same time as this step, organic resin layers 2018 to 2021 in which metal particles are dispersed are formed in the regions not irradiated with the laser light 2010 to 2013. Here, the Ag paste is ejected by the droplet ejection method and irradiated with a laser beam.

Next, as shown in FIG. 20 (A), phosphorus was added to the semiconductor region in a self-aligned manner using the first conductive layers 2014 to 2017 and the organic resin layers 2018 to 2021 in which metal particles were dispersed as masks. It forms the high-concentration impurity region 2030-2034. Phosphorus concentration in the high-concentration impurity region is 1 × 10²⁰~1×10²¹atoms / cm³(Typically 2x10²⁰~5×10²⁰atoms / cm³). Of the semiconductor regions 2003 and 2004, the region overlapping the first conductive layers 2014 to 2017 and the organic resin layers 2018 to 2021 in which metal particles are dispersed is a channel forming region.

Next, a third insulating layer 2035 is formed to cover the first conductive layers 2014 to 2017. Here, an insulating film containing hydrogen is formed. After that, the impurity elements added to the semiconductor region are activated and the semiconductor region is hydrogenated. As the insulating film containing hydrogen, a silicon nitride film (SiNO film) obtained by a sputtering method is used.

Next, after forming an opening reaching the semiconductor region, the second conductive layers 2041 to 2044 are formed. The second conductive layer 2041 functions as the source wiring, the second conductive layer 2042 functions as the first connecting wiring, the second conductive layer 2043 functions as the power supply line, and the second conductive layer 2044 functions as the first connection wiring. Functions as a connection wiring for 2. In this embodiment, a Ti film, an aluminum-silicon alloy film, and a Ti film are continuously formed by a sputtering method to form a three-layer laminated film, which is then etched into a desired shape to form a third conductive film. Form a layer.

Next, as shown in FIG. 20 (B), a fourth insulating layer 2051 is formed. As the fourth insulating layer, an insulating layer that can be flattened is preferable. As the insulating layer that can be flattened, the same materials and methods as those of the third insulating layer 544 shown in the fifth embodiment can be appropriately used. Here, an acrylic resin is formed. By using an organic material such as a black pigment or a dye that absorbs visible light as the fourth insulating layer, the absorption of stray light of the light emitting element formed later is the fourth insulation. It is absorbed by the layers and the contrast of each pixel can be improved.

Next, the fourth insulating layer is provided with an opening in the fourth insulating layer by known photolithography and etching, and a part of the second conductive layer (second connecting wiring) 2044 is exposed. Next, a third conductive layer 2052 is formed. As the third conductive layer 2052, a reflective conductive film and a transparent conductive film are laminated to form a film. Here, an aluminum film containing 1 to 20% nickel and an ITO having silicon oxide are laminated by a sputtering method. Aluminum containing 1 to 20% nickel is preferable because it does not undergo electrolytic corrosion even when it comes into contact with ITO, which is an oxide.

Next, the first mask pattern 2053 is formed by the droplet ejection method. Next, the second mask pattern 2054 is formed by the droplet ejection method. In the first mask pattern 2053, a material having low coatability, here, a solution in which a fluorine-based silane coupling agent is dissolved in an alcohol solvent is discharged by a droplet ejection method. The second mask pattern 2054 is formed by ejecting polyimide by a droplet ejection method, heating it at 200 degrees for 30 minutes, and firing it.

Next, as shown in FIG. 21 (A), after removing the first mask pattern 2053 by ashing with oxygen, the third conductive layer 2052 not covered with the second mask pattern 2054 is etched. To remove. Next, the second mask pattern 2054 is removed to form the fourth conductive layer 2055. The fifth conductive layer functions as a first pixel electrode. The planar structures corresponding to the vertical cross-sectional structures AB and CD in FIG. 21 (A) are shown in FIG. 22, which are referred to at the same time.

Next, a fifth insulating layer 2061 serving as a partition wall (also called a bank, a barrier, a bank, etc.) is formed by covering the end portion of the fourth conductive layer 2055. The fifth insulating layer is a photosensitive or non-photosensitive organic material (polyimide, acrylic, polyamide, polyimideamide, or benzocyclobutene) or a SOG film (for example, a SiOx film containing an alkyl group) having a thickness of 0.8 μm. Use in the range of ~ 1 μm. When the fifth insulating layer is formed by using a photosensitive material, the side surface thereof has a shape in which the radius of curvature changes continuously, and the thin film of the upper layer is formed without being stepped, which is preferable.

Further, as the fifth insulating layer 2061, a material that absorbs visible light such as a dye or a black pigment may be dissolved or dispersed in the organic material to provide an insulating material having a light-shielding property. For example, a material such as COLOR MOSAIC CK (trade name) manufactured by Fuji Film Olin Co., Ltd. is used. In this case, since the fifth insulating layer functions as a black matrix, it can absorb stray light from a light emitting element formed later. As a result, the contrast of each pixel is improved. Furthermore, by providing the fourth insulating layer 2051 with an insulating material having a light-shielding property, it is possible to obtain a total light-shielding effect with the fifth insulating layer 2061.

Next, a layer 2062 containing a luminescent substance is formed on the surface of the fourth conductive layer 2055 and the end portion of the fifth insulating layer 2061 by a vapor deposition method, a coating method, a droplet ejection method, or the like. After that, a fifth conductive layer 2063 that functions as a second pixel electrode is formed on the layer 2062 that contains the luminescent substance. Here, ITO containing silicon oxide is formed into a film by a sputtering method. As a result, the light emitting element can be formed by the fourth conductive layer 2055, the layer 2062 containing the light emitting substance, and the fifth conductive layer 2063. Each material of the conductive layer and the layer containing the light emitting substance constituting the light emitting element is appropriately selected, and each film thickness is also adjusted.

Before forming the layer 2062 containing the luminescent substance, heat treatment at 200 ° C. is performed in atmospheric pressure to remove the moisture adsorbed in or on the surface of the fifth insulating layer 2061. Further, heat treatment is performed at 200 to 400 ° C., preferably 250 to 350 ° C. under reduced pressure to form a layer 2062 containing a luminescent substance by a vacuum deposition method or a droplet ejection method under reduced pressure without exposing it to the atmosphere. It is preferable to do so.

The layer 2062 containing a luminescent substance is formed of a charge injection transport substance containing an organic compound or an inorganic compound and a luminescent material, and is a medium molecular organic compound represented by a low molecular weight organic compound, a dendrimer, an oligomer, etc. from the number of molecules thereof. It contains one or more layers selected from high molecular weight organic compounds, and may be combined with an electron-injection-transporting or hole-injection-transporting inorganic compound.

Among the charge-injected transport substances, a substance having particularly high electron transport property is, for example, tris (8-quinolinolato) aluminum (abbreviation: Alq).₃), Tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq)₃), Bis (10-Hydroxybenzo [h] -Kinorinato) Beryllium (abbreviation: BeBq)₂), Bis (2-methyl-8-quinolinolato) -4-phenylphenylato-aluminum (abbreviation: BAlq), and the like, metal complexes having a quinoline skeleton or a benzoquinoline skeleton, and the like.

Examples of substances with high hole transport properties include 4,4'-bis [N- (1-naphthyl) -N-phenyl-amino] -biphenyl (abbreviation: α-NPD) and 4,4'-bis. [N- (3-Methylphenyl) -N-phenyl-amino] -biphenyl (abbreviation: TPD) and 4,4', 4''-tris (N, N-diphenyl-amino) -triphenylamine (abbreviation:: Aromatic amines such as TDATA), 4,4', 4''-tris [N- (3-methylphenyl) -N-phenyl-amino] -triphenylamine (abbreviation: MTDATA) (ie, benzene ring- Compounds (having a bond of nitrogen) can be mentioned.

Among the charge injection transport substances, the substances with particularly high electron injection properties are lithium fluoride (LiF), cesium fluoride (CsF), and calcium fluoride (CaF).₂) Etc. include alkali metal or alkaline earth metal compounds. In addition, Alq₃It may be a mixture of a substance having high electron transport property such as magnesium (Mg) or an alkaline earth metal.

Among the charge injection transport substances, substances with high hole injection properties include, for example, molybdenum oxide (MoO)._x) And vanadium oxide (VO)_x), Ruthenium oxide (RuO)_x), Tungsten oxide (WO)_x), Manganese oxide (MnO)_x) And other metal oxides. In addition, phthalocyanine (abbreviation: H)₂Examples thereof include phthalocyanine compounds such as Pc) and copper phthalocyanine (CuPc).

The light emitting layer may be configured such that light emitting layers having different light emitting wavelength bands are formed for each pixel to perform color display. Typically, a light emitting layer corresponding to each color of R (red), G (green), and B (blue) is formed. Also in this case, by providing a filter (colored layer) that transmits light in the emission wavelength band on the light emitting side of the pixel, the color purity can be improved and the pixel portion can be mirrored (reflection). It can be prevented. By providing a filter (colored layer) on the light emitting side of the pixel, it is possible to omit a circularly polarized plate or the like, which was conventionally considered necessary, and it is possible to eliminate the loss of light emitted from the light emitting layer. .. Further, it is possible to reduce the change in color tone that occurs when the pixel portion (display screen) is viewed from an oblique angle.

There are various light emitting materials that form the light emitting layer. For low molecular weight organic luminescent materials, 4- (dicyanomethylene) 2-methyl-6- [2- (1,1,7,7-tetramethyldurolysin-9-yl) ethenyl] -4H-pyran (abbreviation:: DCJT), 4- (dicyanomethylene) -2-tert-butyl-6- [2- (1,1,7,7-tetramethyldurolysin-9-yl) ethenyl] -4H-pyran (abbreviation: DCJTB) , Perifrantene, 2,5-dicyano-1,4-bis [2- (10-methoxy-1,1,7,7-tetramethyldurolysin-9-yl) ethenyl] benzene, N, N'-dimethylquinacridone (Abbreviation: DMQd), Methylene 6, Methylene 545T, Tris (8-quinolinolato) Aluminum (Abbreviation: Alq)₃), 9,9'-bianthracene, 9,10-diphenylanthracene (abbreviation: DPA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA) and the like can be used. Further, other substances may be used.

On the other hand, the polymer-based organic light-emitting material has higher physical strength than the low-molecular-weight material, and the durability of the device is high. Further, since it is possible to form a film by coating, it is relatively easy to manufacture the device. The structure of the light emitting element using the high molecular weight organic light emitting material is basically the same as that when the low molecular weight organic light emitting material is used, and becomes a cathode / a layer / anode containing a light emitting substance. However, when forming a layer containing a luminescent substance using a polymer-based organic luminescent material, it is difficult to form a laminated structure as in the case of using a low-molecular-weight organic luminescent material, and in many cases, two layers are formed. It becomes a structure. Specifically, it has a structure of cathode / light emitting layer / hole transport layer / anode.

Since the emission color is determined by the material forming the light emitting layer, it is possible to form a light emitting element exhibiting desired light emission by selecting these. Examples of the polymer-based light-emitting material that can be used for forming the light-emitting layer include polyparaphenylene vinylene, polyparaphenylene, polythiophene, and polyfluorene.

Polyparaphenylene Vinylene-based luminescent materials include poly (paraphenylene vinylene) [PPV] derivatives, poly (2,5-dialkoxy-1,4-phenylene vinylene). [RO-PPV], poly (2- (2'-ethyl-hexoxy) -5-methoxy-1,4-phenylene vinylene) [MEH-PPV], poly (2- (dialkoxyphenyl) -1,4- Phenylene vinylene) [ROPh-PPV] and the like. Polyparaphenylene-based luminescent materials include polyparaphenylene [PPP] derivatives, poly (2,5-dialkoxy-1,4-phenylene) [RO-PPP], and poly (2,5-dihexoxy-1,4). -Phenylene) and the like. Polythiophene-based luminescent materials include polythiophene [PT] derivatives, poly (3-alkylthiophene) [PAT], poly (3-hexylthiophene) [PHT], poly (3-cyclohexylthiophene) [PCHT], and poly (3). -Cyclohexyl-4-methylthiophene) [PCHMT], poly (3,4-dicyclohexylthiophene) [PDCHT], poly [3- (4-octylphenyl) -thiophene] [POPT], poly [3- (4-octyl) Phenyl) -2,2 bithiophene] [PTOPT] and the like. Examples of the polyfluorene-based luminescent material include derivatives of polyfluorene [PF], poly (9,9-dialkylfluorene) [PDAF], and poly (9,9-dioctylfluorene) [PDOF].

Further, the light emitting layer may be configured to emit light of a single color or white. When a white light emitting material is used, it is possible to enable color display by providing a filter (colored layer) that transmits light of a specific wavelength on the light emitting side of the pixel.

To form a light emitting layer that emits white light, for example, Alq₃Alq partially doped with Nile Red, a red luminescent dye₃, P-EtTAZ, and TPD (aromatic diamine) are sequentially laminated by a vapor deposition method to obtain white color. Further, when the light emitting layer is formed by a coating method using spin coating, it is preferable to fire the light emitting layer by vacuum heating after coating. For example, poly (ethylenedioxythiophene) and poly (styrene sulfonic acid) aqueous solution (PEDOT, PSS) are applied to the entire surface as a layer acting as a hole injection layer and fired, and then the light emitting center is used as a layer acting as a light emitting layer. Dyes (1,1,4,4-tetraphenyl-1,3-butadiene (TPB), 4-dicyanomethylene-2-methyl-6- (p-dimethylamino-styrene) -4H-pyran (DCM1), Nile A polyvinyl carbazole (PVK) solution doped with red, coumarin 6, etc.) may be applied to the entire surface and fired.

The light emitting layer may be formed as a single layer, and the electron transporting 1,3,4-oxadiazole derivative (PBD) may be dispersed in the hole transporting polyvinylcarbazole (PVK). In addition, white luminescence can be obtained by dispersing 30 wt% PBD as an electron transporting agent and dispersing four kinds of dyes (TPB, coumarin 6, DCM1, Nile red) in an appropriate amount. In addition to the light emitting element that can obtain white light emission shown here, a light emitting element that can obtain red light emission, green light emission, or blue light emission can be produced by appropriately selecting the material of the light emitting layer.

When the hole-transporting polymer-based organic light-emitting material is sandwiched between the anode and the light-emitting polymer-based organic light-emitting material, the hole injection property from the anode can be improved. Generally, a material dissolved in water together with an acceptor material is applied by a spin coating method or the like. Moreover, since it is insoluble in an organic solvent, it can be laminated with the above-mentioned luminescent organic luminescent material. Examples of the hole-transporting polymer-based organic light-emitting material include a mixture of PEDOT and Drosophila sulfonic acid (CSA) as an acceptor material, and a mixture of polyaniline [PANI] and polystyrene sulfonic acid [PSS] as an acceptor material. ..

Further, as the light emitting layer, a triplet excitation material containing a metal complex or the like may be used in addition to the singlet excitation light emitting material. For example, among the red luminescent pixels, the green luminescent pixels, and the blue luminescent pixels, the red luminescent pixels having a relatively short luminance half time are formed of the triplet excitation luminescent material, and other pixels are formed. The luminescent pixels are formed of a singlet-pumped luminescent material. Since the triplet-pumped light-emitting material has good luminous efficiency, it is characterized in that it consumes less power to obtain the same brightness. That is, when the triplet excitation material is applied to the red pixel, the amount of current flowing through the light emitting element can be small, so that the reliability can be improved. To reduce power consumption, red luminescent pixels and green luminescent pixels may be formed of a triplet excitation luminescent material, and blue luminescent pixels may be formed of a singlet excitation luminescent material. By forming a green light emitting element having high human visual sensitivity with a triplet excitation light emitting material, it is possible to further reduce power consumption.

As an example of the triplet excitation light emitting material, there is a material using a metal complex as a dopant, and metal complexes having platinum as a central metal, which is a third transition series element, and metal complexes having iridium as a central metal are known. There is. The triplet excitation light emitting material is not limited to these compounds, and it is also possible to use a compound having the above-mentioned structure and having an element belonging to the 8th to 10th genera of the periodic table as the central metal.

The substances that form the layers containing the luminescent substances listed above are examples, such as hole injection transport layer, hole transport layer, electron injection transport layer, electron transport layer, light emitting layer, electron block layer, hole block layer, and the like. A light emitting element can be formed by appropriately laminating each functional layer. Further, a mixed layer or a mixed joint may be formed by combining each of these layers. The layer structure of the light emitting layer is variable and, instead of not having a specific electron injection region or light emitting region, it is provided with an electrode exclusively for this purpose or a modification in which a light emitting material is dispersed and provided. Is acceptable as long as it does not deviate from the gist of the present invention.

A light emitting element made of the above material emits light by biasing in the forward direction. The pixels of the display device formed by using the light emitting element can be driven by the simple matrix method or the active matrix method. In any case, each pixel is made to emit light by applying a forward bias at a specific timing, but is in a non-light emitting state for a certain period of time. By applying a bias in the opposite direction to this non-emission time, the reliability of the light emitting element can be improved. The light emitting element has a deterioration mode in which the light emission intensity is lowered under constant driving conditions and a deterioration mode in which the non-light emitting region is expanded in the pixel and the brightness is apparently lowered. It is possible to slow down the progress of deterioration and improve the reliability of the light emitting device.

Next, a transparent protective layer 2064 is formed to cover the light emitting element to prevent the invasion of moisture. The transparent protective layer 2064 includes a silicon nitride film, a silicon oxide film, a silicon oxide film (SiNO film (composition ratio N&gt; O) or SiON film (composition ratio N &lt;O)), and carbon obtained by a sputtering method or a CVD method. A thin film (for example, DLC film, CN film) containing the above as a main component can be used.

By the above steps, a light emitting display panel can be manufactured. A protection circuit for preventing electrostatic breakdown, typically a diode, or the like may be provided between the connection terminal and the source wiring layer (gate wiring layer) or in the pixel portion. In this case, electrostatic breakdown can be prevented by manufacturing in the same process as the above-mentioned TFT and connecting the gate wiring layer of the pixel portion and the drain wiring layer or the source wiring layer of the diode.

Any of the first to eighth embodiments can be applied to this embodiment. Further, as the display panel, the liquid crystal display panel and the light emitting display panel have been described as examples in Examples 2 and 3, but the present invention is not limited to this, and DMD (Digital Micromirror Device), The present invention can be appropriately applied to active display panels such as PDPs (Plasma Display Panels), FEDs (Field Emission Display), and electrophoretic display devices (electronic paper).

The form of the light emitting element applicable in the above embodiment will be described with reference to FIG. 23.

FIG. 23 (A) shows an example in which the first pixel electrode 11 is formed of a translucent oxide conductive material, and is formed of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic%. There is. A layer 16 containing a luminescent substance in which a hole injection layer or a hole transport layer 41, a light emitting layer 42, an electron transport layer or an electron injection layer 43 are laminated is provided on the hole injection layer or the hole transport layer 41. The second pixel electrode 17 is formed by a first electrode layer 33 containing an alkali metal such as LiF or MgAg or an alkaline earth metal and a second electrode layer 34 formed of a metal material such as aluminum. A pixel having this structure can emit light from the first pixel electrode 11 side as shown by an arrow in the figure.

FIG. 23 (B) shows an example in which light is emitted from the second pixel electrode 17, and the first pixel electrode 11 is a metal such as aluminum or titanium, or nitrogen at a concentration equal to or less than the chemical quantitative composition ratio with the metal. It is formed by a first electrode layer 35 formed of a metal material containing, and a second electrode layer 32 formed of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic%. A layer 16 containing a luminescent substance in which a hole injection layer or a hole transport layer 41, a light emitting layer 42, an electron transport layer or an electron injection layer 43 are laminated is provided on the hole injection layer or the hole transport layer 41. The second pixel electrode 17 is formed by a third electrode layer 33 containing an alkali metal such as LiF or CaF or an alkaline earth metal and a fourth electrode layer 34 formed of a metal material such as aluminum. By setting the layer to a thickness of 100 nm or less so that light can be transmitted, it is possible to emit light from the second pixel electrode 17.

FIG. 23 (E) shows an example in which light is emitted from both directions, that is, the first electrode and the second electrode, and a conductive conductive film having a translucent property and a large work function is attached to the first pixel electrode 11. A conductive film having translucency and a small work function is used for the second pixel electrode 17. Typically, the first pixel electrode 11 is formed of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic%, and the second pixel electrode 17 is each LiF having a thickness of 100 nm or less. It may be formed by a third electrode layer 33 containing an alkali metal such as CaF or CaF or an alkaline earth metal and a fourth electrode layer 34 formed of a metal material such as aluminum.

FIG. 23 (C) shows an example in which light is emitted from the first pixel electrode 11, and the layer 16 containing a luminescent substance is an electron transport layer or an electron injection layer 43, a light emitting layer 42, a hole injection layer or a hole. The configuration in which the transport layers 41 are stacked in this order is shown. The second pixel electrode 17 is a second electrode layer 32 formed of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic% from the layer 16 side containing a light emitting substance, and a metal such as aluminum or titanium. Alternatively, it is formed by a first electrode layer 35 formed of a metal material containing nitrogen at a concentration equal to or less than the chemical quantitative composition ratio with the metal. The first pixel electrode 11 is formed by a third electrode layer 33 containing an alkali metal such as LiF or CaF or an alkaline earth metal and a fourth electrode layer 34 formed of a metal material such as aluminum. By setting the layer to a thickness of 100 nm or less so that light can be transmitted, it is possible to emit light from the first pixel electrode 11.

FIG. 23 (D) shows an example in which light is emitted from the second pixel electrode 17, and a layer containing a light emitting substance is formed on the first pixel electrode 11 as an electron transport layer or an electron injection layer 43, a light emitting layer 42, The structure in which the hole injection layer and the hole transport layer 41 are laminated in this order is shown. The first pixel electrode 11 has the same structure as that shown in FIG. 23 (A), and the film thickness is formed so as to be thick enough to reflect the light emitted by the layer containing the luminescent substance. The second pixel electrode 17 is made of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic%. In this structure, the hole injection layer or hole transport layer 41 is formed of an inorganic metal oxide (typically molybdenum oxide or vanadium oxide) to be introduced when the second pixel electrode 17 is formed. Oxygen is supplied to improve the hole injection property, and the drive voltage can be lowered.

FIG. 23 (F) shows an example in which light is radiated from both directions, that is, the first pixel electrode and the second pixel electrode, and the first pixel electrode 11 has a light-transmitting property and a small work function. A film is used, and a conductive film having a translucent property and a large work function is used for the second pixel electrode 17. Typically, the first pixel electrode 11 is formed of a third electrode layer 33 containing an alkali metal such as LiF or CaF or an alkaline earth metal having a thickness of 100 nm or less, and a metal material such as aluminum. The electrode layer 34 of 4 may be formed, and the second pixel electrode 17 may be formed of an oxide conductive material containing silicon oxide at a concentration of 1 to 15 atomic%.

The pixel circuit of the light emitting display panel shown in the above embodiment and its operation configuration will be described with reference to FIG. 24. In a display device in which a video signal is digital, the operation configuration of the light emitting display panel includes a video signal input to a pixel defined by a voltage and a video signal defined by a current. The video signal defined by the voltage includes a video signal having a constant voltage applied to the light emitting element (CVCV) and a video signal having a constant current applied to the light emitting element (CVCC). Further, the video signal defined by the current includes a video signal having a constant voltage applied to the light emitting element (CCCV) and a video signal having a constant current applied to the light emitting element (CCCC). In this embodiment, pixels that perform CVCV operation will be described with reference to FIGS. 24 (A) and 24 (B). Further, the pixels that perform the CVCC operation will be described with reference to FIGS. 24 (C) to 24 (F).

In the pixels shown in FIGS. 24A and 24B, a signal line 3710 and a power supply line 3711 are arranged in the column direction, and a scanning line 3714 is arranged in the row direction. It also has a switching TFT3701, a driving TFT3703, a capacitive element 3702, and a light emitting element 3705.

The switching TFT3701 and the driving TFT3703 operate in a linear region when they are on. Further, the driving TFT 3703 has a role of controlling whether or not a voltage is applied to the light emitting element 3705. It is preferable that both TFTs have the same conductive type in the manufacturing process, and in this embodiment, they are formed as p-channel type TFTs. Further, as the driving TFT3703, not only the enhancement type but also the depletion type TFT may be used. The ratio (W / L) of the channel width W and the channel length L of the driving TFT 3703 is preferably 1 to 1000, although it depends on the mobility of the TFT. The larger the W / L, the better the electrical characteristics of the TFT.

In the pixels shown in FIGS. 24A and 24B, the switching TFT3701 controls the input of a video signal to the pixel, and when the switching TFT3701 is turned on, the video signal is input into the pixel. Then, the voltage of the video signal is held by the capacitive element 3702.

In FIG. 24 (A), when the power supply line 3711 is Vss and the counter electrode of the light emitting element 3705 is Vdd, that is, in the cases of FIGS. 23 (C), (D), and (F) (reverse stacking structure), the light emitting element. The counter electrode is the anode, and the electrode connected to the driving TFT 3703 is the cathode. In this case, it is possible to suppress the uneven brightness due to the variation in the characteristics of the driving TFT 3703.

In FIG. 24 (A), when the power supply line 3711 is Vdd and the counter electrode of the light emitting element 3705 is Vss, that is, in the cases of FIGS. 23 (A), (B) and (E) (forward stacking structure), the light emitting elements face each other. The electrode is the cathode and the electrode connected to the driving TFT 3703 is the anode. In this case, by inputting a video signal having a voltage higher than Vdd to the signal line 3710, the voltage of the video signal is held by the capacitive element 3702, and the driving TFT3703 operates in the linear region. Can be improved.

The pixels shown in FIG. 24 (B) are the same as those shown in FIG. 24 (A), except that the TFT 3706 and the scanning line 3715 are added.

The TFT3706 is controlled on or off by a newly arranged scanning line 3715. When the TFT3706 is turned on, the charge held in the capacitive element 3702 is discharged and the TFT3703 is turned off. That is, by arranging the TFT 3706, it is possible to forcibly create a state in which no current flows through the light emitting element 3705. Therefore, the TFT 3706 can be called an erasing TFT. Therefore, in the configuration of FIG. 24 (B), the lighting period can be started at the same time as or immediately after the start of the writing period without waiting for the writing of the signal to all the pixels, so that the duty ratio of light emission can be improved. Is possible.

In the pixel having the above operation configuration, the current value of the light emitting element 3705 can be determined by the driving TFT 3703 that operates in the linear region. With the above configuration, it is possible to suppress the variation in the characteristics of the TFT, and it is possible to provide a display device in which the unevenness of the brightness of the light emitting element due to the variation in the TFT characteristics is improved and the image quality is improved.

Next, the pixels that perform the CVCC operation will be described with reference to FIGS. 24 (C) to 24 (F). As for the pixels shown in FIG. 24 (C), a power supply line 3712 and a current control TFT 3704 are provided in the pixel configuration shown in FIG. 24 (A).

The pixels shown in FIG. 24 (E) are the same as the pixels shown in FIG. 24 (C) except that the gate electrode of the driving TFT 3703 is connected to the power supply line 3712 arranged in the row direction. It is a composition. That is, both pixels shown in FIGS. 24 (C) and 24 (E) show the same equivalent circuit diagram. However, when the power line 3712 is arranged in the column direction (Fig. 24 (C)) and when the power line 3712 is arranged in the row direction (Fig. 24 (E)), each power line has a different layer. It is formed of a conductive film. Here, paying attention to the wiring to which the gate electrode of the driving TFT3703 is connected, it is described separately as FIGS. 24 (C) and 24 (E) in order to show that the layers for producing these are different.

The switching TFT3701 operates in the linear region, and the driving TFT3703 operates in the saturation region. Further, the driving TFT 3703 has a role of controlling the current value flowing through the light emitting element 3705, and the current control TFT 3704 has a role of operating in the saturation region and controlling the supply of the current to the light emitting element 3705.

The pixels shown in FIGS. 24 (D) and 24 (F) are shown in FIGS. 24 (C) and 24 (E), respectively, except that the erasing TFT 3706 and the scanning line 3715 are added to the pixels shown in FIGS. 24 (C) and 24 (E). The pixel configuration is the same as that shown in (E).

It is possible to perform CVCC operation even with the pixels shown in FIGS. 24 (A) and 24 (B). Further, for the pixels having the operation configurations shown in FIGS. 24 (C) to 24 (F), Vdd and Vss are appropriately changed depending on the current flow direction of the light emitting element, as in FIGS. 24 (A) and 24 (B). Is possible.

In the pixel having the above configuration, since the current control TFT 3704 operates in the linear region, a slight fluctuation in Vgs of the current control TFT 3704 does not affect the current value of the light emitting element 3705. That is, the current value of the light emitting element 3705 can be determined by the driving TFT 3703 that operates in the saturation region. With the above configuration, it is possible to provide a display device in which the brightness unevenness of the light emitting element due to the variation in the characteristics of the TFT is improved and the image quality is improved.

In particular, when forming a thin film transistor having an amorphous semiconductor or the like, it is preferable to increase the area of the semiconductor film of the driving TFT because the variation of the TFT can be reduced. Therefore, the pixels shown in FIGS. 24 (A) and 24 (B) have a small number of TFTs, so that the aperture ratio can be increased.

Although the configuration in which the capacitance element 3702 is provided is shown, the present invention is not limited to this, and if the capacitance for holding the video signal is the gate capacitance or the like and can be covered, the capacitance element 3702 is not provided. You may.

Further, when the semiconductor region of the thin film transistor is formed of an amorphous semiconductor film, the threshold value is likely to shift. Therefore, it is preferable to provide a circuit for correcting the threshold value in or around the pixel.

Such an active matrix type light emitting device is considered to be advantageous because it can be driven at a low voltage because a TFT is provided for each pixel when the pixel density increases. On the other hand, it is also possible to form a passive matrix type light emitting device in which a TFT is provided for each row. The passive matrix type light emitting device has a high aperture ratio because each pixel is not provided with a TFT.

Further, in the display device of the present invention, the screen display driving method is not particularly limited, and for example, a point-sequential driving method, a line-sequential driving method, a surface-sequential driving method, or the like may be used. Typically, the line sequential drive method may be used, and a time division gradation drive method or an area gradation drive method may be appropriately used. Further, the video signal input to the source line of the display device may be an analog signal or a digital signal, and a drive circuit or the like may be appropriately designed according to the video signal.

As described above, various pixel circuits can be adopted.

In this embodiment, the implementation of the drive circuit on the display panel shown in the above embodiment will be described with reference to FIG. 26.

As shown in FIG. 26 (A), the signal line drive circuit 1402 and the scanning line drive circuits 1403a and 1403b are mounted around the pixel unit 1401. In FIG. 26 (A), mounting methods using known anisotropic conductive adhesives and anisotropic conductive films as the signal line drive circuit 1402 and the scanning line drive circuits 1403a, 1403b, etc., COG method, and wire bonding The IC chip 1405 is mounted on the substrate 1400 by the method and the reflow processing using solder bumps. Here, the COG method is used. Then, the IC chip and the external circuit are connected via the FPC (Flexible Print Circuit) 1406.

Further, as shown in FIG. 26 (B), when the TFT is formed of SAS or a crystalline semiconductor, the pixel portion 1401 and the scanning line drive circuits 1403a, 1403b, etc. are integrally formed on the substrate, and the signal line drive circuit 1402, etc. May be mounted separately as an IC chip. In FIG. 26B, the IC chip 1405 is mounted on the substrate 1400 by the COG method as the signal line drive circuit 1402. Then, the IC chip and the external circuit are connected via the FPC1406.

Further, as shown in FIG. 26C, a signal line drive circuit 1402 or the like may be mounted by the TAB method instead of the COG method. Then, the IC chip and the external circuit are connected via the FPC1406. In FIG. 26C, the signal line drive circuit is mounted by the TAB method, but the scanning line drive circuit may be mounted by the TAB method.

When the IC chip is mounted by the TAB method, a large pixel portion can be provided on the substrate, and a narrow frame can be achieved.

The IC chip is formed by using a silicon wafer, but instead of the IC chip, an IC in which the IC is formed on a glass substrate (hereinafter referred to as a driver IC) may be provided. Since the IC chip is taken out from a circular silicon wafer, there are restrictions on the shape of the base substrate. On the other hand, in the driver IC, the base substrate is glass and there are no restrictions on the shape, so that the productivity can be improved. Therefore, the shape and dimensions of the driver IC can be freely set. For example, if the length of the long side of the driver IC is set to 15 to 80 mm, the required number can be reduced as compared with the case where the IC chip is mounted. As a result, the number of connection terminals can be reduced, and the manufacturing yield can be improved.

The driver IC can be formed by using a crystalline semiconductor formed on a substrate, and the crystalline semiconductor may be formed by irradiating a continuous oscillation type laser beam. The semiconductor film obtained by irradiating a continuous oscillation type laser beam has few crystal defects and has crystal grains having a large particle size. As a result, the transistor having such a semiconductor film has good mobility and response speed, can be driven at high speed, and is suitable for a driver IC.

In this embodiment, the display module will be described. Here, as an example of the display module, the liquid crystal module is shown with reference to FIG.

The active matrix substrate 1601 and the opposing substrate 1602 are fixed by a sealing material 1600, and a pixel portion 1603 and a liquid crystal layer 1604 are provided between them to form a display area.

The colored layer 1605 is necessary for color display, and in the case of the RGB method, colored layers corresponding to each of the red, green, and blue colors are provided corresponding to each pixel. Polarizing plates 1606 and 1607 are arranged on the outside of the active matrix substrate 1601 and the facing substrate 1602. In addition, a protective film 1616 is formed on the surface of the polarizing plate 1606 to cushion the impact from the outside.

The wiring board 1610 is connected to the connection terminal 1608 provided on the active matrix board 1601 via the FPC 1609. A pixel drive circuit (IC chip, driver IC, etc.) 1611 is provided in the FPC or the connection wiring, and an external circuit 1612 such as a control circuit and a power supply circuit is incorporated in the wiring board 1610.

The cold cathode fluorescent lamp 1613, the reflector 1614, and the optical film 1615 are backlight units, which serve as light sources and project light onto the liquid crystal display panel. The liquid crystal panel, light source, wiring board, FPC, etc. are held and protected by the bezel 1617.

Any of the first to eighth embodiments can be applied to this embodiment.

In this embodiment, the appearance of the light emitting display module will be described with reference to FIG. 25 as an example of the display module. FIG. 25 (A) is a top view of a panel in which the space between the first substrate and the second substrate is sealed by the first sealing material 1205 and the second sealing material, and FIG. 25 (B) is shown in FIG. 25 (B). Corresponds to the cross-sectional view in A-A'in FIG. 25 (A).

In FIG. 25 (A), 1201 shown by a dotted line is a signal line (source line) drive circuit, 1202 is a pixel unit, and 1203 is a scanning line (gate line) drive circuit. In this embodiment, the signal line drive circuit 1201, the pixel unit 1202, and the scanning line drive circuit 1203 are in the region sealed by the first seal material 1205 and the second seal material. As the first sealing material 1205, it is preferable to use a highly viscous epoxy resin containing a filler. Further, as the second sealing material, it is preferable to use an epoxy resin having a low viscosity. Further, it is desirable that the first sealing material 1205 and the second sealing material are materials that do not allow moisture or oxygen to permeate as much as possible.

Further, a desiccant may be provided between the pixel portion 1202 and the first sealing material 1205. Further, a desiccant may be provided on the scanning line or the signal line in the pixel portion. As a desiccant, water (H) is chemically adsorbed by oxides of alkaline earth metals such as calcium oxide (CaO) and barium oxide (BaO).₂It is preferable to use a substance that adsorbs O). However, the present invention is not limited to this, and a substance that adsorbs water by physical adsorption such as zeolite or silica gel may be used.

Further, it can be fixed to the second substrate 1204 in a state where the highly moisture-permeable resin contains the granular substance of the desiccant. Here, examples of the highly breathable resin include acrylic resins such as ester acrylate, ether acrylate, ester urethane acrylate, ether urethane acrylate, butadiene urethane acrylate, special urethane acrylate, epoxy acrylate, amino resin acrylate, and acrylic resin acrylate. Can be used. In addition, bisphenol A type liquid resin, bisphenol A type solid resin, bromine epoxy resin, bisphenol F type resin, bisphenol AD type resin, phenol type resin, cresol type resin, novolak type resin, cyclic aliphatic epoxy resin, epibis type Epoxy resins such as epoxy resins, glycidyl ester resins, glycidyl amine resins, heterocyclic epoxy resins, and modified epoxy resins can be used. Further, other substances may be used. Further, for example, an inorganic substance such as siloxane polymer, polyimide, PSG (phosphorus glass), BPSG (phosphorus glass), etc. may be used.

By providing the desiccant in the area that overlaps with the scanning line, and by fixing the desiccant to the second substrate in a state where the highly breathable resin contains the granular substance of the desiccant, the aperture ratio is not reduced. In addition, it is possible to suppress the intrusion of moisture into the display element and the deterioration caused by it.

Note that 1210 is a connection wiring for transmitting signals input to the signal line drive circuit 1201 and the scanning line drive circuit 1203, and is connected from the FPC (flexible print wiring) 1209, which is an external input terminal, via the connection wiring 1208. Receives video and clock signals.

Next, the cross-sectional structure will be described with reference to FIG. 25 (B). A drive circuit and a pixel portion are formed on the first substrate 1200, and have a plurality of semiconductor elements typified by TFT. A signal line drive circuit 1201 and a pixel unit 1202 are shown as drive circuits. The signal line drive circuit 1201 is formed as a CMOS circuit in which an n-channel type TFT1221 and a p-channel type TFT1222 are combined.

In this embodiment, the signal line drive circuit, the scanning line drive circuit, and the TFT of the pixel portion are formed on the same substrate. Therefore, the volume of the light emitting display device can be reduced.

Further, the pixel portion 1202 is formed by a plurality of pixels including a first pixel electrode (anode) 1213 composed of a switching TFT 1211 and a reflective conductive film electrically connected to the driving TFT 1212 and its drain. To.

The interlayer insulating film 1220 of these TFTs 1211, 1212, 1221, 1222 includes an inorganic material (silicon oxide, silicon nitride, silicon oxide nitride, etc.), an organic material (polyimide, polyamide, polyimideamide, benzocyclobutene, or siloxane). It can be formed using a material containing (polymer) as a main component. Further, when a siloxane polymer is used as a raw material for the interlayer insulating film, the insulating film has a structure having silicon and oxygen in the skeleton structure and hydrogen or / and an alkyl group in the side chain.

Insulations (called banks, partition walls, barriers, banks, etc.) 1214 are formed at both ends of the first pixel electrode (anode) 1213. In order to improve the coverage of the film formed on the insulator 1214, a curved surface having a curvature is formed at the upper end or the lower end of the insulator 1214. As the material of the insulator 1214, a material whose main component is an inorganic material (silicon oxide, silicon nitride, silicon oxide nitride, etc.) or an organic material (polyimide, polyamide, polyimideamide, benzocyclobutene, or siloxane polymer) is used. Can be formed. Further, the insulator 1214 may be covered with a protective film (flattening layer) made of an aluminum nitride film, an aluminum nitride film, a thin film containing carbon as a main component, or a silicon nitride film. Further, by using an organic material obtained by dissolving or dispersing a material that absorbs visible light such as a black pigment or a dye as the insulator 1214, stray light from a light emitting element formed later can be absorbed. As a result, the contrast of each pixel is improved. Further, by providing the interlayer insulating film 1220 with an insulating material having a light-shielding property, it is possible to obtain a total light-shielding effect with the insulating material 1214.

Further, an organic compound material is vapor-deposited on the first pixel electrode (anode) 1213 to selectively form a layer 1215 containing a luminescent substance.

In this way, a light emitting element 1217 composed of a first pixel electrode (anode) 1213, a layer 1215 containing a light emitting substance, and a second pixel electrode (cathode) 1216 is formed. The light emitting element 1217 emits light to the second substrate 1204 side.

As the light emitting element 1217, the structure shown in the fifth embodiment can be appropriately used.

In addition, a protective laminate 1218 is formed to seal the light emitting element 1217. The protective laminate is composed of a first inorganic insulating film, a stress relaxation film, and a second inorganic insulating film. Next, the protective laminate 1218 and the second substrate 1204 are bonded with the first sealing material 1205 and the second sealing material 1206. It is preferable to drop the second sealing material using a device for dropping the sealing material, such as the device for dropping the liquid crystal shown in FIG. 15 of Example 3. After the sealing material is dropped or discharged from the dispenser to apply the sealing material on the active matrix substrate, the second substrate and the active matrix substrate are bonded to each other in a vacuum, and UV curing is performed to seal the sealing material. it can.

A polarizing plate 1225 is fixed on the surface of the second substrate 1204, and a 1 / 2λ or 1 / 4λ retardation plate 1229 and an antireflection film 1226 are provided on the surface of the polarizing plate 1225. Further, the retardation plate of the 1 / 4λ plate, the retardation plate 1229 of the 1 / 2λ plate, and the polarizing plate 1225 may be provided in order from the second substrate 1204. By providing a retardation plate or a polarizing plate, it is possible to prevent external light from being reflected by the pixel electrodes. The first pixel electrode 1213 and the second pixel electrode 1216 are formed of a light-transmitting or semi-translucent conductive film, and the interlayer insulating film 1223 is a material that absorbs visible light or absorbs visible light. When the material is formed by using an organic material obtained by dissolving or dispersing the material, external light is not reflected by each pixel electrode, so that it is not necessary to use a retardation plate and a polarizing plate.

The connection wiring 1208 and the FPC 1209 are electrically connected by an anisotropic conductive film or an anisotropic conductive resin 1227. Further, it is preferable to seal the connection portion between each wiring layer and the connection terminal with a sealing resin. With this structure, it is possible to prevent moisture from the cross section from invading the light emitting element and deteriorating it.

A space filled with an inert gas, for example, nitrogen gas, may be provided between the second substrate 1204 and the protective laminate 1218. It is possible to increase the prevention of invasion of water and oxygen.

A colored layer can be provided between the pixel portion 1202 and the polarizing plate 1225. In this case, full-color display can be performed by providing a light emitting element capable of emitting white light in the pixel portion and separately providing a colored layer indicating RGB on the second substrate 1204. Further, a full-color display can be performed by providing a light emitting element capable of emitting blue light in the pixel portion and separately providing a color conversion layer or the like. Further, it is also possible to form a light emitting element that emits red, green, and blue light from each pixel portion, and to use a colored layer. Such a display module has high color purity of each RBG and enables high-definition display.

Further, a light emitting display module may be formed on one or both of the first substrate 1200 and the second substrate 1204 by using a substrate such as a film or a resin. By sealing without using the facing substrate in this way, it is possible to improve the weight reduction, miniaturization, and thinning of the display device.

Any of the first to eighth embodiments can be applied to this embodiment. Further, examples of a liquid crystal display module and a light emitting display module are shown as display modules, but the present invention is not limited to this, and DMD (Digital Micromirror Device), PDP (Plasma Display Panel), and the like. It can be appropriately applied to display modules such as FED (Field Emission Display) and electrophoretic display device (electronic paper).

Various electronic devices can be manufactured by incorporating the display device shown in the above embodiment into the housing. Electronic devices include television devices, video cameras, cameras such as digital cameras, goggle-type displays (head mount displays), navigation systems, sound playback devices (car audio, audio components, etc.), personal computers, game devices, mobile information. A terminal (mobile computer, mobile phone, portable game machine, electronic book, etc.), an image playback device equipped with a recording medium (specifically, a recording medium such as a Digital Versatile Disc (DVD)) is played back and the image is displayed. A device equipped with a mobile display) and the like. Here, as typical examples of these electronic devices, a television device and its block diagram are shown in FIGS. 27 and 28, respectively, and a digital camera is shown in FIG. 29, respectively.

FIG. 27 is a diagram showing a general configuration of a television device that receives an analog television broadcast. In FIG. 27, the radio wave for television broadcasting received by the antenna 1101 is input to the tuner 1102. The tuner 1102 generates and outputs an intermediate frequency (IF) signal by mixing the radio frequency television signal input from the antenna 1101 with a signal having a local oscillation frequency controlled according to a desired reception frequency.

The IF signal extracted by the tuner 1102 is amplified to a required voltage by the intermediate frequency amplifier (IF amplifier) 1103, then image-detected by the image detection circuit 1104, and is audio-detected by the audio detection circuit 1105. The video signal output by the video detection circuit 1104 is separated into a brightness signal and a color signal by the video processing circuit 1106, and further subjected to predetermined video signal processing to obtain a video signal, which is a representative of the display device of the present invention. These include liquid crystal display devices, light emitting display devices, DMDs (Digital Micromirror Devices), PDPs (Plasma Display Panels), FEDs (Field Emission Display), and electrophoretic display devices (EMD). It is output to the video system output unit 1108 such as electronic paper). A display device using a liquid crystal display device is a liquid crystal television, and a display device using a light emitting display device is an EL (Electro Luminescence) television. The same applies when another display device is used.

Further, the signal output by the voice detection circuit 1105 is subjected to processing such as FM demodulation by the voice system processing circuit 1107 to become a voice signal, which is appropriately amplified and output to the voice system output unit 1109 such as a speaker.

The television device using the present invention is not limited to those compatible with terrestrial broadcasting such as VHF band and UHF band, cable broadcasting, and analog broadcasting such as BS broadcasting, and terrestrial digital broadcasting, cable digital broadcasting, etc. Alternatively, it may be compatible with BS digital broadcasting.

FIG. 28 is a perspective view of the television device as viewed from the front, and includes a housing 1151, a display unit 1152, a speaker unit 1153, an operation unit 1154, a video input terminal 1155, and the like. The configuration is as shown in FIG. 27.

The display unit 1152 is an example of the image system output unit 1108 of FIG. 27, and displays an image here.

The speaker unit 1153 is an example of the audio system output unit of FIG. 27, and outputs audio here.

The operation unit 1154 is provided with a power switch, a volume switch, a channel selection switch, a tuner switch, a selection switch, etc., and by pressing the button, the television device can be turned on / off, video can be selected, and audio can be adjusted. And select the tuner. Although not shown, the above selection can be made by the remote controller type operation unit.

The video input terminal 1155 is a terminal for inputting a video signal from the outside such as a VTR, a DVD, or a game machine to a television device.

When the television device shown in this embodiment is a wall-mounted television device, a wall-mounted portion is provided on the back surface of the main body.

By using a display device which is an example of the semiconductor device of the present invention for the display unit of the television device, it is possible to manufacture the television device at low cost and with high throughput and yield. Further, by using the semiconductor device of the present invention for the CPU that controls the video detection circuit, the video processing circuit, the voice detection circuit, and the voice processing circuit of the television device, a television device can be manufactured at low cost and with high throughput and yield. be able to. Therefore, it can be applied to various uses as a display medium having a particularly large area, such as a wall-mounted television device, an information display board at a railway station or an airport, or an advertisement display board on a street.

29 (A) and 29 (B) are diagrams showing an example of a digital camera. FIG. 29 (A) is a perspective view seen from the front side of the digital camera, and FIG. 29 (B) is a perspective view seen from the rear side direction. In FIG. 29 (A), the digital camera is provided with a release button 1301, a main switch 1302, a finder window 1303, a flash 1304, a lens 1305, a lens barrel 1306, and a housing 1307.

Further, in FIG. 29B, a finder eyepiece window 1311, a monitor 1312, and an operation button 1313 are provided.

When the release button 1301 is pressed halfway, the focus adjustment mechanism and the exposure adjustment mechanism are activated, and when it is pressed all the way to the bottom, the shutter opens.

The main switch 1302 switches the power of the digital camera ON / OFF by pressing or rotating.

The finder window 1303 is arranged above the lens 1305 on the front surface of the digital camera, and is a device for confirming the range and focus position of the image taken from the finder eyepiece window 1311 shown in FIG. 29 (B).

The flash 1304 is arranged in the upper part of the front surface of the digital camera, and emits auxiliary light at the same time when the release button is pressed and the shutter is opened when the subject brightness is low.

The lens 1305 is located in front of the digital camera. The lens is composed of a focusing lens, a zoom lens, and the like, and constitutes a photographing optical system together with a shutter and an aperture (not shown). An image sensor such as a CCD (Charge Coupled Device) is provided behind the lens.

The lens barrel 1306 moves the position of the lens in order to focus the focusing lens, the zoom lens, and the like. At the time of shooting, the lens barrel 1305 is moved toward the front by extending the lens barrel. Also, when carrying it, the lens 1305 is retracted to make it compact. In this embodiment, the structure is such that the subject can be zoomed by extending the lens barrel, but the structure is not limited to this structure, and the lens barrel is configured by the structure of the photographing optical system in the housing 1307. A digital camera capable of zoom shooting without extending the camera may be used.

The viewfinder eyepiece window 1311 is provided on the upper part of the rear surface of the digital camera, and is a window provided for eyepieces when confirming the shooting range and the focus position.

The operation button 1313 is various function buttons provided on the rear surface of the digital camera, and is composed of a setup button, a menu button, a display button, a function button, a selection button, and the like.

By using the display device, which is an embodiment of the semiconductor device of the present invention, as a monitor, it is possible to manufacture a digital camera at low cost and with high throughput and yield. In addition, it controls the CPU that receives operation inputs such as various function buttons, main switch, and release button and performs related processing, the circuit that performs automatic focus operation and automatic focus adjustment operation, the drive control circuit for strobe light emission, and the drive of CCD. Timing control circuit, imaging circuit that generates image signal from signal photoelectrically converted by imaging element such as CCD, A / D conversion circuit that converts image signal generated by imaging circuit into digital signal, image data to memory By using the semiconductor device of the present invention for a CPU or the like that controls each circuit such as a memory interface for writing and reading image data, it is possible to manufacture a digital camera at low cost and with high throughput and yield.

<figref num="1">The perspective view explaining the manufacturing process of the wiring which concerns on this invention.</figref><figref num="2">The top view explaining the manufacturing process of the wiring which concerns on this invention.</figref><figref num="3">The cross-sectional view explaining the wiring which concerns on this invention.</figref><figref num="4">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="5">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="6">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="7">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="8">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="9">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="10">The figure explaining the droplet ejection device applicable to this invention.</figref><figref num="11">The figure explaining the laser beam direct drawing apparatus applicable to this invention.</figref><figref num="12">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="13">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="14">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="15">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="16">The top view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="17">The figure explaining the liquid crystal dropping method applicable to this invention.</figref><figref num="18">The figure explaining the structure of the liquid crystal display module which concerns on this invention.</figref><figref num="19">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="20">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="21">The cross-sectional view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="22">The top view explaining the manufacturing process of the semiconductor device which concerns on this invention.</figref><figref num="23">The figure explaining the form of the light emitting element applicable to this invention.</figref><figref num="24">The figure explaining the equivalent circuit of the light emitting element applicable to this invention.</figref><figref num="25">The figure explaining the structure of the light emitting display panel which concerns on this invention.</figref><figref num="26">The top view explaining the mounting method of the drive circuit of the display device which concerns on this invention.</figref><figref num="27">A block diagram illustrating an example of an electronic device.</figref><figref num="28">The figure explaining an example of an electronic device.</figref><figref num="29">The figure explaining an example of an electronic device.</figref><figref num="30">The figure explaining the contact angle of the region with low wettability and the region with high wettability.</figref><figref num="31">The cross-sectional view explaining the wiring which concerns on this invention.</figref><figref num="32">The figure explaining the resistance value of the wiring which concerns on this invention.</figref>