Non-single crystal transistor integrated circuit and its manufacturing method

The present invention relates to a non-single crystal transistor integrated circuit such as a polycrystalline silicon transistor, an amorphous silicon transistor, and an organic transistor, and a method for manufacturing the same.

In recent years, integrated circuits using non-single crystal transistors such as organic transistors have attracted attention in order to realize functions that are difficult to realize with single crystal transistors such as silicon (for example, increasing the area and ensuring mechanical flexibility). Has been done.<nplcit num="1"><text>CUT-AND-PASTE ORGANIC FET CUSTOMIZED ICS FOR APPLICATION TO ARTIFICIAL SKIN, T. Someya, H. Kawaguchi, and T. Sakurai, Technical Digest of 2004 IEEE International Solid-State Circuits Conference (ISSCC 2004), San Francisco Marriott, San Francisco, CA, February 14-19, 2004, No. 16.2, Page 288.</text></nplcit>

<p> The demand for higher functionality of such non-single crystal transistors tends to increase, and in particular, it is desired to have the following functions. (1) Reduction of the occupied area of non-single crystal transistors. (2) Highly accurate pressure detection. (3) Highly accurate distortion detection. (4) Easy black-and-white discrimination in the photo detector. (5) Improved resolution. (6) Protection of non-crystalline transistors from mechanical shock and pressure. (7) Improvement of operating speed of non-crystal transistors.</p><p> An object of the present invention is to provide a non-single crystal transistor integrated circuit having higher functionality and a method for manufacturing the same.</p>

<p> The method for manufacturing a non-single crystal transistor integrated circuit according to the present invention includes a step of forming a through hole in a polymer film, a step of electrically connecting both sides of the polymer film through the through hole, and the polymer film. The step of providing the non-single crystal transistor on one surface and the polymer film on which the non-single crystal transistor is formed are superposed in the vertical direction with N layers (N is a natural number of 2 or more), and the through hole is formed. It is characterized by including a step of electrically connecting the non-single crystal transistors of each polymer film through.</p><p> The non-single crystal transistor integrated circuit according to the present invention (hereinafter referred to as "first non-single crystal transistor integrated circuit") is a polymer film in which N layers (N is a natural number of 2 or more) are laminated in the vertical direction. A single crystal transistor is provided on one side of each of the polymer films, and a through hole for electrically connecting both sides is formed through the through hole, and the single crystal transistor of each polymer film is formed through the through hole. Is characterized by being electrically connected.</p><p> Another non-single crystal transistor integrated circuit according to the present invention (hereinafter, referred to as "second non-single crystal transistor integrated circuit") includes a first polymer film, a common electrode provided on the polymer film, and a common electrode. The dielectric provided on the common electrode, the second polymer film provided on the dielectric, and the thickness of the dielectric when pressure is applied to the second polymer film. It is characterized by including a pressure sensor that reads out the amount of change in capacitance as a change in capacitance, and a non-single crystal transistor provided on the second polymer film for reading out the pressure sensor.</p><p> The other non-single crystal transistor integrated circuit according to the present invention (hereinafter referred to as "third non-single crystal transistor integrated circuit") includes a first polymer film, a common electrode provided on the polymer film, and a common electrode. When a piezoelectric polymer material provided on the common electrode, a second polymer film provided on the dielectric, and a second polymer film provided on the second polymer film are subjected to pressure or bent and deformed. It is characterized by including a strain sensor that reads out the amount of deformation of the piezoelectric polymer material as strain, and a non-single crystal transistor provided on the second polymer film for reading out the strain sensor. ..</p><p> Another non-single crystal transistor integrated circuit according to the present invention (hereinafter, referred to as fourth non-single crystal transistor integrated circuit) is provided with a transparent polymer film having an opening and a light-shielding portion, and the light-shielding portion. An electrode, a first-type non-single crystal material layer provided on the electrode, a second-type non-single crystal material layer provided on the first-type non-single crystal material layer, and the first type. A transparent electrode provided on the non-single crystal material layer of type 2, a polymer film provided on the transparent electrode, and a non-single crystal transistor provided on the polymer film and electrically connected to the transparent electrode. It is characterized by having and.</p><p> The other non-single crystal transistor integrated circuit according to the present invention (hereinafter referred to as "fifth non-single crystal transistor integrated circuit") is a cell of m rows and n columns (m and n are both natural numbers of 2 or more). A switching function connected to a detection means and a sensor in which each of these cells detects a predetermined physical quantity and / or scientific characteristic, and includes means for selecting the seconds and / or columns of the array. It is characterized in that it has a non-single crystal transistor having the above, and the array of the cell is roughly scanned for each predetermined unit, and is read out finely later only when there is a response.</p><p> The other non-single crystal transistor integrated circuit according to the present invention (hereinafter, referred to as sixth non-single crystal transistor integrated circuit) is a polymer film and a non-single crystal provided on one surface of the polymer film. It is characterized by including a transistor and a protective film for protecting the non-single crystal transistor.</p><p> The other non-single crystal transistor integrated circuit according to the present invention (hereinafter referred to as "seventh non-single crystal transistor integrated circuit") is a polymer film and a non-single crystal provided on one surface of the polymer film. The non-single crystal transistor including a transistor includes a gate electrode, a gate insulating film in which the thickness of the channel portion is smaller than that of other portions, and a non-single crystal provided at a portion corresponding to the channel portion. It is characterized by having a material and a source electrode and a drain electrode provided on the gate insulating film so as to be electrically connected to the non-single crystal material.</p>

<p> According to the method for manufacturing a non-single crystal transistor integrated circuit in the present invention, a through hole is formed in the polymer film, both sides of the polymer film are electrically connected through the through hole, and one of the polymer films is electrically connected. Non-single crystal transistors are provided on the surface, and polymer films on which the non-single crystal transistors are formed are laminated in the vertical direction with N layers (N is a natural number of 2 or more), and each polymer film is not formed through a through hole. Electrically connect single crystal transistors.</p><p> Since the carrier mobility in the non-single crystal semiconductor is about three orders of magnitude smaller than that in the single crystal semiconductor (for example, silicon), the operating speed of the non-single crystal transistor is also slowed down accordingly. Therefore, in order to secure a sufficient current required for circuit operation, it is necessary to take a large ratio (W / L) of the channel length (L) and the channel width (W).</p><p> In general, miniaturization of non-single crystal transistors is more difficult than that of silicon, and the channel length is usually about 1 to 100 microns when printing technology is used, and miniaturization is also limited. As a result, it is necessary to make the channel width very large, which increases the occupied area of the non-crystal transistor and remarkably increases the area of the integrated circuit using the non-crystal transistor. Therefore, the integrated circuit may not be laid out within a desired area.</p><p> On the other hand, since non-single crystal semiconductors (particularly organic semiconductors) are sensitive to heat, once the non-crystalline semiconductor is coated on the substrate, the heating process cannot be applied. Since a heating process is required to apply the insulating film, which is a component of the non-crystalline transistor, it is necessary to apply the insulating film before applying the non-crystalline semiconductor.</p><p> One effective method for avoiding an increase in the occupied area of non-single crystal transistors and advancing the application of integrated circuits of non-single crystal transistors is to consider a method of stacking non-single crystal transistors in the vertical direction. it can. However, as described above, since the non-single crystal semiconductor is sensitive to heat, the next insulating film cannot be formed after the non-single crystal transistor is formed. This means that the next non-single crystal transistor cannot be formed on top of the non-single crystal transistor in the method of applying the thin film layer in order from the bottom of the base material.</p><p> In the method for manufacturing a non-single crystal transistor integrated circuit according to the present invention, since the non-single crystal transistors are superposed in the vertical direction without using a heating process, the occupied area of the non-single crystal transistor can be reduced. It should be noted that a dummy sheet that prevents a step from occurring between the polymer films can be further provided.</p><p> According to the first non-single crystal transistor integrated circuit, the area occupied by the non-single crystal transistor can be reduced by superimposing the non-single crystal transistors in the vertical direction.</p><p> According to the second non-single crystal transistor integrated circuit, when a pressure is applied, the pressure can be detected with high accuracy by reading out the amount of change in the thickness of the dielectric as a change in capacitance.</p><p> According to the third non-single crystal transistor integrated circuit, it is possible to detect strain with high accuracy by reading out the amount of deformation of the piezoelectric polymer material as strain when pressure is applied or it is bent and deformed. Become.</p><p> According to the fourth non-single crystal transistor integrated circuit, it is possible to easily distinguish between 1 and 0 of the amount of light, so that black and white can be easily discriminated by the photodetector.</p><p> According to the fifth non-single crystal transistor integrated circuit, the resolution is improved by roughly scanning the cell array for each predetermined unit and then finely reading it only when there is a response.</p><p> According to the sixth non-single crystal transistor integrated circuit, the non-crystal transistor can be protected from mechanical shock and pressure by the protective film for protecting the non-single crystal transistor.</p><p> According to the seventh non-single crystal transistor integrated circuit, the operating speed of the non-crystal transistor is improved by making the thickness of the channel portion of the gate insulating film smaller than that of the other portions.</p>

Embodiments of the non-single crystal transistor integrated circuit according to the present invention and the method for manufacturing the same will be described in detail with reference to the drawings. In the following description of the embodiment, a case where the non-single crystal transistor is an organic transistor will be described unless otherwise specified. FIG. 1 is a diagram for explaining a method for manufacturing a non-single crystal transistor integrated circuit according to the present invention. In this case, first, a through-hole process is performed on a polymer film (base film) 1 such as a polyimide film or a polyethylene terephthalate (PET) film.

For the through-hole processing of the polymer film 1, drilling is performed by using an NC drilling machine, a laser processing machine, or a plastic injection molding machine. Through the holes formed in this way, electrical conduction is established between the electrodes 2 and 3 on the front and back surfaces. At this time, it is usual to start with a polymer film 1 having a metal foil on the entire front and back surfaces, and to perform patterning of the gate electrode 4 after the drilling / conduction process. This is not the only case.

Next, the gate insulating film 5 such as polyimide is applied by spin coating and cured in an oven. After that, a part of the polyimide is peeled off by a method such as laser processing to prepare for forming vias.

Further, the organic semiconductor layer 6 such as pentacene is formed by a vapor deposition method or the like. At the time of this vapor deposition, the organic semiconductor layer 6 is formed only at necessary locations by using a metal mask, and the elements are separated. Finally, the source electrode 7 and the drain electrode 8 are formed to complete the organic transistor 9.

After forming the integrated circuit of the organic transistor 9 in this way, N sheets having the integrated circuit of the organic transistor 9 (N is a natural number of 2 or more. In the case of FIG. 1, 3) are laminated and bonded. Although the integrated circuits of the organic transistors 9 can be individually formed, it is also possible to form a plurality of integrated circuits on one sheet at a time and cut out individual circuits from the sheets.

At the time of bonding, if shapes different from each other are bonded together, a step is generated, which is not preferable. Therefore, the shapes of the sheets to be bonded are made uniform in advance. If the shapes of the sheets are not the same, prepare a dummy sheet so that there is no step.

FIG. 2 shows a first embodiment of the non-single crystal transistor integrated circuit according to the present invention. In this integrated circuit, a polymer film 11, a common electrode 12 supported by the polymer film 11, an insulating film 13, and a polymer film 14 are formed in this order, and a capacitance type pressure sensor 15 and an organic transistor 16 are integrated on the polymer film 14. Will be done. The common electrode 12 constitutes a capacitor together with electrodes 17 and 18 arranged at intervals L.

When such a capacitance type pressure sensor 14 is used, when a pressure is applied in the direction of the arrow, the change in the thickness of the insulating film 13 as a dielectric is read out as the change in capacitance. According to the present embodiment, the pressure can be read out in a controlled manner in the region where the amount of change in the thickness of the insulating film 13 changes linearly with respect to the pressure.

Conventionally, a pressure type sensor that reads out the change in the thickness of the dielectric as a change in capacitance when the pressure changes has existed, but forming a matrix with such a sensor as an area type increases the number of elements. Then it is difficult. The reason is that the change in capacitance could not be read out due to stray capacitance due to wiring.

Such inconvenience can be avoided by adopting an active matrix method in which each sensor cell includes a non-single crystal transistor such as an organic transistor 15 in order to read out the capacitance type pressure sensor 14. In particular, a flexible and large-area active matrix can be inexpensively constructed by using the organic transistor 15. Further, by combining the capacitance type pressure sensor 14 and a non-single crystal transistor such as the organic transistor 15, high impedance measurement becomes possible, and the capacitance type and accurate pressure mapping can be read out.

FIG. 3 shows a second embodiment of the non-single crystal transistor integrated circuit according to the present invention. In this integrated circuit, a polymer film 21, a common electrode 22 supported by the polymer film 21, a polymer piezoelectric material portion 23 such as polyvinylidene fluoride (PVDF), and a polymer film 24 are formed in this order, and the polymer film 24 is formed on the polymer film 24. The strain sensor 25 and the organic transistor 26 are integrated. The common electrode 22 constitutes a capacitor together with the electrodes 27 and 28. By using the polymer piezoelectric material section 23, a good array of strain sensors can be constructed.

FIG. 4 shows a third embodiment of the non-single crystal transistor integrated circuit according to the present invention. This integrated circuit consists of a transparent polymer film 33 having an opening portion 31 and a light-shielding portion 32, an electrode 34 made of aluminum, silver, etc., an N-type organic semiconductor 35 made of perylene, etc., and copper phthalocyanine. It includes a P-type organic semiconductor 36 composed of the above, a transparent electrode 37 composed of ITO and the like, a polymer film 38, and an organic transistor 39.

The transparent polymer film 33, the electrode 34, the N-type organic semiconductor 35, the P-type organic semiconductor 36, the transparent electrode 37, and the polymer film 38 provided with the opening portion 31 and the light-shielding portion 32 form a reflective photodetector and form an opening. The light 40 that has passed through the portion 31 and is reflected by the polymer film 38 is incident on the transparent electrode 37. When the light 40 is incident on the portion corresponding to the black portion of the object (for example, paper) 41 to be imaged, the amount of light of the light 40 becomes 0. On the other hand, when the light 40 is incident on the portion corresponding to the white portion of the target 41, the amount of light of the light 40 becomes 1. By discriminating between 0 and 1 in the amount of light in this way, a good image capture can be configured.

FIG. 5 shows a fourth embodiment of the non-single crystal transistor integrated circuit according to the present invention. This integrated circuit is connected to the sensor array 51 of 16 rows and 16 columns and the sensor array 51 through word lines 0,1,2,3, ..., C, D, E, F, and low addresses R1 to R4 are connected. It includes a row decoder 52 having a row, and a column selector 53 having a column address C0 and the like.

Since the response speed of a non-single crystal transistor such as an organic transistor is slower than that of a single crystal transistor, progressive scanning is effective. In the case of artificial skin, it is generally considered that only some of the sensors in the sensor array 51 are pressed and most of the sensors are not. Also, in the case of a scanner, the part that is usually drawn in black is a part, and most of it remains white. For this reason, it is not necessary to carefully perform a raster scan of the entire sensor from the beginning. First, a rough scan is performed in small units such as 2 rows and 2 columns, and then only the part where the signal exists is read out in detail later. It is expected to increase the response speed of. In this way, a progressive scan is a process in which a coarse scan is performed in small units such as 2 rows and 2 columns, and then only the part where the signal exists is read out later.

In FIG. 5, a case where a progressive scan is performed in units of 2 rows and 2 columns will be described. When the scanner Progressive bar signal shown in FIG. 5 is low, two word lines adjacent to each other become 0. At this time, if any one of the data outputs D0, D1, D2, and D3 becomes 1, it means that the signal is included in any of the regions of 2 rows and 2 columns. If any one of the data outputs D0, D1, D2, and D3 is 1, the scanner Progressive bar signal may be set high and a fine scan may be performed.

In the configuration shown in FIG. 5, by using a liquid crystal panel display as a light source, a structure that does not integrate with an organic transistor can be adopted. In this case, only one line is illuminated on the liquid crystal panel display. Scanning such illuminated rows eliminates the need for organic transistors. By configuring the photodiodes in array or area units and connecting them in the bit direction, it is not necessary to connect the photodiodes in the word direction. Furthermore, instead of illuminating one line at a time, illuminating one or two lines every other bit produces a staggered effect, so the resolution can be increased.

FIG. 6 shows a fifth embodiment of the non-single crystal transistor integrated circuit according to the present invention. In this integrated circuit, a protective rubber sheet 63 such as silicone rubber and a polymer film 64 are attached in order to the side of the polymer film 61 on which the organic transistor 62 is provided, and the organic transistor of the polymer film 61 is attached. The pressure-sensitive conductive rubber 65 and the polymer film 66 are provided in this order on the side where the 62 is not provided.

In an organic transistor having a low molecular weight semiconductor as a channel layer, the adhesion between the organic semiconductor and other materials is poor, so that the organic semiconductor layer may be easily peeled off from the gate insulating film or the source electrode in contact with the organic semiconductor layer. And the drain electrode may come off. These fears are especially pronounced in applications such as artificial skin where flexibility is important. In addition, in contact-type devices such as artificial skin where mechanical pressure is applied, the organic semiconductor layer may easily peel off. Therefore, it is effective to introduce a layer that absorbs mechanical shock and pressure. As in the present embodiment, the rubber sheet 63 is placed in order to protect the organic semiconductor layer of the organic transistor 62 from impact and pressure.

FIG. 6 shows a sixth embodiment of the non-single crystal transistor integrated circuit according to the present invention. The organic transistor of this integrated circuit includes a polymer film 71, a gate electrode 72 provided on the polymer film 71, a gate insulating film 73 covering the polymer film 71, an insulating film 74 provided on the insulating film 74, an organic semiconductor layer 75, and the like. It includes an insulating film 76, a source electrode 77 provided on the insulating film 74, and a drain electrode 78 provided on the insulating film 76.

It is preferable to make the thickness of the channel portion of the gate insulating film 73 as small as possible, but the thickness of the contact region and the wiring portion of the gate insulating film 73 is from the viewpoint of reducing the capacitance of the capacitor and increasing the operating speed of the circuit. , It is preferable to make it larger than other parts. When a polymer material is used for the gate insulating film 73, it is preferable to form the gate insulating film 73 by a spin coating method in order to stably form the gate insulating film 73 having a relatively thin channel portion. However, in the case of the spin coating method, the film thickness of the insulating film cannot be changed locally. Therefore, after forming a gate insulating film having a certain film thickness by spin coating, a predetermined thick film pattern is applied by using a printing technique such as screen printing.

The present invention is not limited to the above-described embodiment, and many modifications and modifications can be made. For example, in the above embodiment, the case where the non-single crystal transistor is an organic transistor has been described, but any other type of non-single crystal transistor such as a polycrystalline silicon transistor and an amorphous silicon transistor can also be used.

In a non-single crystal transistor integrated circuit manufactured by the manufacturing method shown in FIG. 1, each sheet may have a sensor or a moving part, and each sheet has a function of applying a voltage, a function of supplying a current, and a light wave. It can also have at least one of the functions that generate.

<figref num="1">It is a figure for demonstrating the manufacturing method of the non-single crystal transistor integrated circuit by this invention.</figref><figref num="2">The first embodiment of the non-single crystal transistor integrated circuit according to this invention is shown.</figref><figref num="3">A second embodiment of the non-single crystal transistor integrated circuit according to the present invention is shown.</figref><figref num="4">A third embodiment of the non-single crystal transistor integrated circuit according to the present invention is shown.</figref><figref num="5">A fourth embodiment of the non-single crystal transistor integrated circuit according to the present invention is shown.</figref><figref num="6">A fifth embodiment of the non-single crystal transistor integrated circuit according to the present invention is shown.</figref><figref num="7">A sixth embodiment of the non-single crystal transistor integrated circuit according to the present invention is shown.</figref>

Code description

1,11,12,14,21,24,38,61,64,66,71 Polymer film 2,3,17,18,27,28,34 Electrode 4,72 Gate electrode 5,73 Gate insulating film 6 , 26,75 Organic semiconductor layer 7,77 Source electrode 8,78 Drain electrode 9,16,39,62 Organic transistor 10 sheets 12,22 Common electrode 13,74,76 Insulation film 15 Capacitive pressure sensor 23 Polymer Hydraulic material part 25 Strain sensor 31 Opening part 32 Light-shielding part 33 Transparent polymer film 35 N-type organic semiconductor 36 P-type organic semiconductor 37 Transparent electrode 40 Light 41 Target 51 Sensor array 52 Row (row) decoder 53 Column (column) selector 63 Protective rubber sheet 65 Pressure-sensitive conductive rubber