JP4830489B2 - Organic thin film transistor manufacturing method, organic thin film transistor manufactured by the manufacturing method, and sheet thereof - Google Patents

Description

  The present invention relates to an organic thin film transistor and a method for manufacturing the same.

  In recent years, various organic thin film transistors using organic semiconductors have been proposed. Organic thin-film transistors (TFTs) are being researched and developed as devices for displays and electronic tags that can be manufactured by a simple process such as printing using a plastic support. As an organic thin film transistor, an all-polymer type organic TFT technology is disclosed (for example, refer to Patent Document 1).

  In addition, the conventional organic thin film transistor needs to keep the contact resistance between the source electrode, the drain electrode and the organic semiconductor layer low, and gold, platinum, or a heavy doped conductive polymer such as polyethylene dioxythiophene and polystyrene. It is common to use a sulfonic acid complex (for example, see Patent Document 2).

  Although the technology of Patent Document 1 proposes manufacturing by a simple process by ink jet or coating, the obtained organic TFT has a high gate voltage, a low current value in a switching ON state, and a current ON / OFF state. There are problems such as low value.

  In addition, when an electrode as described in Patent Document 2 is used, there is a problem in durability as an element because of low adhesion and mechanical strength with the support. Therefore, it has been difficult to realize an organic TFT device that operates stably on a flexible substrate. In addition, when the conductive polymer is used, the contact resistance can be kept low, but the conductive polymer itself has a high resistivity and has practical difficulties.

As a technique for improving semiconductor performance and durability, the present applicant proposed in Japanese Patent Application No. 2002-306861 that the source electrode and the drain electrode are each composed of two layers containing different conductive materials, but the manufacturing is complicated. In addition, TFT carrier mobility is not sufficient.
International Publication No. 01/47043 Pamphlet JP 2000-307172 A

  The present invention has been made in view of the above circumstances, and the object thereof is to be able to continuously form organic TFTs on a flexible base such as a polymer support, and thus the manufacturing cost can be greatly reduced, and An object of the present invention is to provide an organic thin film transistor excellent in semiconductor performance such as durability and a method for producing the same.

  In order to achieve the above object, one aspect of the present invention is to form a layer containing a thermoplastic semiconductor material and a layer containing metal fine particles to be bonded to the layer, and heating after pressing or pressing and heating simultaneously. There is a method for manufacturing an organic thin film transistor to be a semiconductor layer, a source electrode, and a drain electrode.

It is a figure which shows the structural example of the organic TFT which concerns on this invention. It is a figure which shows the structural example of the organic TFT which concerns on this invention. It is a figure which shows the structural example of the organic TFT which concerns on this invention. It is a figure which shows the structural example of the organic TFT which concerns on this invention. It is a figure which shows one example of arrangement | positioning of the organic capacitor | condenser TFT sheet of an additional capacitor type. It is an example of the sheet | seat which has arrange | positioned the storage capacitor type organic TFT. It is an example of the schematic equivalent circuit diagram of an organic TFT sheet. It is a conceptual diagram of the structure of the organic TFT of this invention.

The above object of the present invention is achieved by the following configurations.
(1) An organic layer that includes a layer containing a thermoplastic semiconductor material and a layer containing metal fine particles bonded to the layer and is heated after pressing or is pressed and heated simultaneously to form a semiconductor layer, a source electrode, and a drain electrode. A method for manufacturing a thin film transistor.
(2) The manufacturing method of the organic thin-film transistor as described in said (1) heated at the temperature more than the softening point of a thermoplastic semiconductor material.
(3) The manufacturing method of the organic thin-film transistor as described in said (1) or (2) heated at the temperature more than the temperature which metal fine particles heat-seal | fuse.
(4) The manufacturing method of the organic thin-film transistor of any one of said (1)-(3) whose average particle diameter of metal microparticles is 20 nm or less.
(5) The method for producing an organic thin film transistor according to any one of (1) to (4), wherein the layer containing the metal fine particles contains a conductive polymer.
(6) The method for producing an organic thin film transistor according to any one of (1) to (5), wherein the thermoplastic semiconductor material is a π-conjugated material.
(7) An organic thin film transistor manufactured by the manufacturing method according to any one of (1) to (6).
(8) An organic thin film transistor in which a source electrode and a drain electrode are mixed in a semiconductor layer in which at least a part of a metal phase constituting the electrode includes a thermoplastic semiconductor material and bonded to the semiconductor layer.
(9) The organic thin film transistor according to (8), wherein the metal phase is formed by thermally fusing metal fine particles.
(10) A plurality of organic thin film transistors connected through a gate bus line and a source bus line are formed on a support sheet, and the source electrode and the drain electrode of the thin film transistor are at least one of the metal phases constituting the electrode. An organic thin film transistor sheet in which a part is mixed in a semiconductor layer containing a thermoplastic semiconductor material and bonded to the semiconductor layer.
(11) The organic thin film transistor sheet according to (10), wherein the metal phase is formed by thermally fusing metal fine particles.

  In other words, the present inventors have found that the metal fine particles are fused and mixed into the semiconductor layer by heat and pressure, thereby reducing the contact resistance between the semiconductor layer and the electrode and increasing the strength of the electrode, thereby supporting the TFT constituent layer and the support layer. The present inventors have considered that the adhesion to the body will be improved, and have reached the present invention.

  In the manufacture of an organic TFT, the present invention forms a layer containing a thermoplastic semiconductor material and a layer containing metal fine particles to be bonded to the layer, and is heated after pressing or simultaneously pressing and heating to form a semiconductor layer, a source An electrode and a drain electrode are used. Thereby, as shown in the conceptual diagram of FIG. 5, the source electrode and the drain electrode of the organic thin film transistor are mixed with the organic conductor layer containing the thermoplastic semiconductor material so that at least a part of the metal phase constituting the electrode is mixed. It joins to a semiconductor layer.

  That is, the effect of the present invention is that a structure in which at least a part of metal fine particles are fused to each other, and a metal phase forming a source electrode and a drain electrode is embedded in a part of an organic semiconductor layer containing a thermoplastic semiconductor material. It is thought that it is obtained by having With such a structure, as shown in FIG. 5, the junction area between the semiconductor layer and the source electrode and the drain and the electrode is increased, so that the contact resistance can be reduced.

  The organic semiconductor material used in the present invention is a thermoplastic organic semiconductor material having a softening point or a melting point, and can be appropriately selected from, for example, known organic semiconductor materials.

  Examples of such organic semiconductor materials include π-conjugated polymers such as polypyrrole, polythiophene, polychenylene vinylene, polyacetylene, polyisothianaphthene, polyfuran, polyphenylene, derivatives thereof, and copolymers containing their unit components. .

  The softening point or melting point of the organic semiconductor material is preferably 50 to 300 ° C., more preferably 80 to 200 ° C. As such a material, for example, F8T2 (a copolymer of fluorene derivative and bithiophene described in WO 01/47043) ) And poly (3-alkylthiophene) ordered structures. Moreover, the thiophene copolymer described in US Patent Publication 2003-0160230, 2003-016234, 2003-0136958, etc. can also be used. In addition to these semiconductor materials, π-conjugated polymers having a structure in which an alkyl group is substituted on the π-conjugated main chain and exhibiting liquid crystallinity upon thermal softening can be suitably used.

  As a method for forming a layer containing these thermoplastic semiconductor materials, a vacuum deposition method, a molecular beam epitaxial growth method, an ion cluster beam method, a low energy ion beam method, an ion plating method, a CVD method, a sputtering method, a plasma polymerization method, Examples include electrolytic polymerization, chemical polymerization, spray coating, spin coating, blade coating, dip coating, casting, roll coating, bar coating, die coating, and LB. it can. However, among these, in terms of productivity, spin coating, blade coating, dip coating, roll coating, bar coating, die coating, etc. can be used to form a thin film easily and precisely using a solution of a semiconductor material. preferable. Alternatively, the layer may be formed by discharging a solution or dispersion of a semiconductor material by inkjet and drying and removing the solvent.

  Metal materials of metal fine particles are platinum, gold, silver, cobalt, nickel, chromium, copper, iron, tin, antimony, lead, tantalum, indium, palladium, tellurium, rhenium, iridium, aluminum, ruthenium, germanium, molybdenum, tungsten, Zinc or the like can be used, but platinum, gold, silver, copper, cobalt, chromium, iridium, nickel, palladium, molybdenum, and tungsten having a work function of 4.5 eV or more are particularly preferable.

  The fine particles made of these metals are patterned by applying a liquid, paste or ink dispersed in a dispersion medium which is preferably water, an organic solvent or a mixture thereof, preferably using a dispersion stabilizer made of an organic material.

  As a method for producing such a metal fine particle dispersion, metal ions are reduced in the liquid phase, such as a physical generation method such as gas evaporation method, sputtering method, metal vapor synthesis method, colloid method, coprecipitation method, etc. Examples of the chemical production method for producing metal fine particles include the colloidal methods described in JP-A-11-76800, JP-A-11-80647, JP-A-11-319538, JP-A-2000-239853, and the like. This is a fine metal particle dispersion produced by a gas evaporation method described in Kabuki 2001-254185, 2001-53028, 2001-35255, 2000-124157, 2000-123634, and the like.

  The average particle diameter of the dispersed metal fine particles is preferably 20 nm or less from the viewpoint of the effect of the present invention.

  Moreover, it is preferable to contain a conductive polymer in the metal fine particle dispersion, and if the source electrode and the drain electrode are formed by patterning and pressing and heating, ohmic contact with the organic semiconductor layer is possible by the conductive polymer. it can. That is, the effect of the present invention can be further enhanced by interposing a conductive polymer on the surface of the metal fine particles, reducing the contact resistance to the semiconductor, and thermally fusing the metal fine particles.

  As the conductive polymer, it is preferable to use a known conductive polymer whose conductivity has been improved by doping or the like. For example, conductive polyaniline, conductive polypyrrole, conductive polythiophene, a complex of polyethylene dioxythiophene and polystyrene sulfonic acid, etc. Are preferably used.

  The content of the metal fine particles is preferably 0.00001 to 0.1 in terms of mass ratio with respect to the conductive polymer. If this amount is exceeded, fusion of the metal fine particles may be inhibited.

  After these metal fine particle dispersions are bonded to a layer containing a thermoplastic semiconductor material by a method described later to form the layer, the solvent is dried. After bonding with the layer containing the thermoplastic organic semiconductor material, 1) the embedded structure is formed by heating and pressing (heating and pressing), and at the same time, the metal fine particles are thermally fused to form the source electrode and the drain electrode. 2) After forming the embedded structure by heating and pressing, the metal fine particles are further thermally fused at a temperature equal to or higher than the thermal fusion temperature of the metal fine particles to form the source electrode and the drain electrode. 3) By pressing Any method of forming a source and a drain by thermally fusing metal fine particles at a temperature equal to or higher than the heat fusing temperature of the metal fine particles after forming the embedded structure is preferable. ) Or 2), and most preferred is 1). In addition, although the procedure is limited by the softening point or melting point of the thermoplastic organic semiconductor material and the temperature and time at which at least a part of the metal fine particles are fused, in the case of 1) and 2), for example, It is preferable that the temperature at the time is equal to or higher than the softening point of the thermoplastic semiconductor material.

  Moreover, although the pressure range of the said press depends on the hardness at the time of thermoplasticity of a semiconductor layer, it is 1-50000Pa in general, Furthermore, 1000-10000Pa are preferable.

  In the present invention, the thermoplastic semiconductor material and the metal fine particles are heated and pressurized simultaneously, thereby strengthening the physical junction between them, reducing the contact resistance, and increasing the current when the transistor is switched. Can do. The order of the formation of the layer containing the metal fine particles and the formation of the layer containing the thermoplastic semiconductor material is not particularly limited.

  Various methods can be used as a method of patterning like an electrode using the metal fine particle dispersion, and a method of heating and pressing after forming a layer containing a thermoplastic semiconductor material and a layer containing metal fine particles. Specific examples will be shown in the examples described later.

  For example, as a patterning of the metal fine particle dispersion, a printing method is first mentioned. The fine metal particle dispersion is patterned using ink, and the printing method can be patterned by any printing method such as letterpress printing, screen printing, planographic printing, intaglio printing, stencil printing, etc. . There is also a method of patterning by an ink jet method. In other words, the metal fine particle dispersion is ejected from the ink jet head and the metal fine particle dispersion is patterned, and the ejection method from the ink jet head is an on-demand type such as a piezo method or a bubble jet (registered trademark) method, or a static method. Patterning can be performed by a known method such as a continuous jet type ink jet method such as an electrosuction method.

  As a method for heating and pressurizing, a known method including a method used for a heating laminator or the like can be used.

  1A to 1D show structural examples of the organic TFT according to the present invention.

  In FIG. 1A, a pattern (2, 3) containing metal fine particles is formed on a support 6 on which a known gas barrier film is formed by the method described above, and then a thermoplastic semiconductor material is formed thereon. The layer 1 including the metal fine particles and the layer including the thermoplastic semiconductor material are heated and pressed to form the semiconductor layer 1, the source electrode 2 and the drain electrode 3, and the insulating layer 5 is formed thereon. Further, an organic TFT is formed by forming a gate electrode 4 thereon.

  In FIG. 1B, a layer 1 containing a thermoplastic semiconductor material is formed on a support 6, and then a layer containing metal fine particles is patterned and heated and pressed to form a semiconductor layer 1, a source electrode 2, and a drain electrode 3. The insulating layer 5 and the gate electrode 4 are formed thereon.

  In FIG. 1C, after forming the gate electrode 4 on the support 6, the insulating layer 5 is formed, and the pattern (2, 3) is formed on the layer containing the metal fine particles by the method described above. A layer 1 containing a thermoplastic semiconductor material is formed on the substrate, and then a layer containing metal fine particles and a layer containing a thermoplastic semiconductor material are heated and pressurized to form a semiconductor layer 1, a source electrode 2, and a drain electrode 3, thereby forming an organic TFT. Is formed.

  In FIG. 1D, after forming the gate electrode 4 on the support 6, the insulating layer 5 is formed, and the layer 1 containing the thermoplastic semiconductor material is formed on the entire surface by coating, and the metal is formed thereon. A layer containing fine particles is patterned and heated and pressed to form the semiconductor layer 1, the source electrode 2, and the drain electrode 3.

  FIG. 2 shows an example of the arrangement of the organic TFT sheet. The organic TFT is an additional capacitor type. First, the gate electrode 4 is provided on the support 6, and the channel is formed of the semiconductor layer 1 through the gate insulating layer 5. The source electrode 2 and the drain electrode 3 are connected to each other, and they are connected to the sheet-like support via the gate bus line 7 and the source bus line 8. Reference numeral 9 denotes a pixel electrode, and 20 denotes an additional capacitor. FIG. 3 shows an example of a sheet on which storage capacitor type organic TFTs are arranged. Reference numeral 21 denotes a storage capacitor.

  FIG. 4 is an example of a schematic equivalent circuit diagram of an organic TFT sheet.

  The organic TFT sheet 10 has a large number of organic TFTs 11 arranged in a matrix. 7 is a gate bus line of each TFT 11, and 8 is a source bus line of each TFT 11. An output element 12 is connected to the source electrode of each TFT 11, and this output 12 is, for example, a liquid crystal, an electrophoretic element or the like, and constitutes a pixel in the display device. The pixel electrode may be used as an input electrode of the photosensor. In the illustrated example, a liquid crystal as an output element is shown by an equivalent circuit composed of a resistor and a capacitor. 13 is a storage capacitor, 14 is a vertical drive circuit, and 15 is a horizontal drive circuit.

  In the present invention, for example, a material having a functional group such as acrylic acid, acetamide, dimethylamino group, cyano group, carboxyl group, nitro group, benzoquinone derivative, tetracyanoethylene, and tetracyanoquinodimethane are used in the organic semiconductor layer. And materials that can accept electrons, such as derivatives thereof, materials that have functional groups such as amino groups, triphenyl groups, alkyl groups, hydroxyl groups, alkoxy groups, and phenyl groups, substituted amines such as phenylenediamine , So-called doping, containing materials that serve as donors of electrons such as anthracene, anthracene, benzoanthracene, substituted benzoanthracene, pyrene, substituted pyrene, carbazole and its derivatives, tetrathiafulvalene and its derivatives, etc. Processing Good.

  The doping means introducing an electron-donating molecule (acsector) or an electron-donating molecule (donor) into the thin film as a dopant. Therefore, the doped thin film is a thin film containing the condensed polycyclic aromatic compound and the dopant. As the dopant used in the present invention, either an acceptor or a donor can be used, and known materials and processes can be used.

  The film thickness of the semiconductor layer is not particularly limited, but the characteristics of the obtained TFT are largely affected by the film thickness of the semiconductor layer, and the film thickness varies depending on the semiconductor material, but is generally 1 μm or less. In particular, 10 to 300 nm is preferable.

  The gate electrode is not particularly limited as long as it is a conductive material, and any material can be used. As a method of forming the gate electrode, a method of forming a conductive thin film formed using a method such as vapor deposition or sputtering, using a known photolithography method or a lift-off method, thermal transfer onto a metal foil such as aluminum or copper, There is a method of etching using a resist such as inkjet. Alternatively, the conductive polymer solution or dispersion, or the conductive fine particle dispersion may be directly patterned by ink jetting, or may be formed from the coating film by lithography or laser ablation. Furthermore, a method of patterning an ink containing a conductive polymer or conductive fine particles, a conductive paste, or the like by a printing method such as relief printing, intaglio printing, planographic printing, or screen printing can also be used.

  As the gate insulating layer, various insulating materials can be used, and an inorganic oxide film having a high relative dielectric constant is particularly preferable. Inorganic oxides include silicon oxide, aluminum oxide, tantalum oxide, titanium oxide, tin oxide, vanadium oxide, barium strontium titanate, barium zirconate titanate, lead zirconate titanate, lead lanthanum titanate, strontium titanate, Examples thereof include barium titanate, barium magnesium fluoride, bismuth titanate, strontium bismuth titanate, strontium bismuth tantalate, bismuth tantalate niobate, and yttrium trioxide. Of these, silicon oxide, aluminum oxide, tantalum oxide, and titanium oxide are preferable. Inorganic nitrides such as silicon nitride and aluminum nitride can also be suitably used.

  As a method for forming the inorganic oxide film, a dry process such as a vacuum deposition method, a molecular beam epitaxial growth method, an ion cluster beam method, a low energy ion beam method, an ion plating method, a CVD method, a sputtering method, an atmospheric pressure plasma method, Examples include wet processes such as spray coating, spin coating, blade coating, dip coating, casting, roll coating, bar coating, die coating, and other coating methods, and printing and inkjet patterning methods. Can be used depending on the material. The wet process is a method of applying and drying a liquid in which fine particles of inorganic oxide are dispersed in an arbitrary organic solvent or water using a dispersion aid such as a surfactant as required, or an oxide precursor, for example, A so-called sol-gel method in which a solution of an alkoxide body is applied and dried is used. Among these, the atmospheric pressure plasma method is preferable.

  Plasma film formation under atmospheric pressure refers to a process in which a thin film is formed on a substrate by discharging at atmospheric pressure or a pressure near atmospheric pressure to excite reactive gas to form a thin film on a substrate. No. 11-133205, JP-A No. 2000-185362, JP-A No. 11-61406, JP-A No. 2000-147209, JP-A No. 2000-121804, etc. (hereinafter also referred to as atmospheric pressure plasma method). Accordingly, a highly functional thin film can be formed with high productivity.

  In addition, as the organic compound film, polyimide, polyamide, polyester, polyacrylate, photo radical polymerization type, photo cation polymerization type photo curable resin, or a copolymer containing an acrylonitrile component, polyvinyl phenol, polyvinyl alcohol, novolac resin, Also, phosphazene compounds including cyanoethyl pullulan, polymer bodies, elastomer bodies, and the like can be used.

  As the method for forming the organic compound film, the wet process is preferable. An inorganic oxide film and an organic oxide film can be laminated and used together. The thickness of the gate insulating layer is generally 50 nm to 3 μm, preferably 100 nm to 1 μm.

  The support is composed of glass or a flexible resin sheet. For example, a plastic film can be used as the sheet. Examples of the plastic film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), Examples thereof include films made of cellulose triacetate (TAC), cellulose acetate propionate (CAP), and the like. Thus, by using a plastic film, the weight can be reduced as compared with the case of using a glass substrate, the portability can be improved, and the resistance to impact can be improved.

  Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to these examples.

Example 1
A thermal oxide film having a thickness of 200 nm was formed on an n-type Si wafer having a specific resistance of 0.01 Ω · cm, immersed in a 1 mol / L NaOH aqueous solution, and thoroughly washed with ultrapure water. Furthermore, after being immersed in a toluene solution (1% by mass) of octadecyltrichlorosilane for 10 minutes, the thermal oxide film was surface-treated by rinsing with toluene and drying.

Next, a well-purified regioregular body (manufactured by Aldrich) of poly (3-hexylthiophene) by a chelate washing method using EDTA (ethylenediaminetetraacetic acid disodium salt) is prepared and bubbled with N ₂ gas. Then, dissolved oxygen in the solution was removed, and the surface of the silicon oxide film was applied using an applicator in an N ₂ gas atmosphere, dried at room temperature, and then subjected to heat treatment at 50 ° C. for 30 minutes. At this time, the film thickness of poly (3-hexylthiophene) was 50 nm.

  After preparing an aqueous dispersion of silver fine particles having an average particle size of 30 nm using the production method described in JP-A-11-80647, a PSS (polystyrene sulfonic acid) complex of PEDOT (polyethylenedioxythiophene), which is a conductive polymer, is prepared. An aqueous dispersion (BAYTRON P manufactured by Bayer) and 0.01% by mass of a nonionic surfactant (polyoxyethylene alkyl ether) were added to obtain a layer forming material containing metal fine particles. Here, the mass ratio between the silver fine particles and the conductive polymer was adjusted to be 5000: 1.

  Further, the layer forming material containing the metal fine particles was discharged into a source electrode and a drain electrode by a piezo ink jet and dried.

  Next, in a nitrogen gas atmosphere, while heating the Si wafer substrate to 250 ° C., a silicone rubber roller having a surface temperature of 250 ° C. was pressed against the source and drain electrode portions while applying a pressure of 5000 Pa, and the electrode portions were fused. In addition, the bonding surface on the semiconductor layer side is embedded in the semiconductor layer.

Thus, an organic TFT having a channel length L = 30 μm and a channel width W = 1 mm was produced. This TFT operated well as a p-channel channel enhancement type FET, and the mobility in the saturation region was 0.015 cm ² / V · s.

Example 2
An organic TFT was produced in the same manner as in Example 1 except that silver fine particles having an average particle diameter of 30 nm used for the layer forming material containing metal fine particles were changed to an aqueous dispersion of silver fine particles having an average particle diameter of 20 nm.

Example 3
An organic TFT was produced in the same manner as in Example 1 except that an aqueous dispersion of silver fine particles having an average particle diameter of 10 nm was used as the layer forming material containing metal fine particles.

Comparative Example 1
An organic TFT was produced in the same manner as in Example 3 except that the conductive polymer was not added to the layer forming material containing metal fine particles and no pressing was performed during heating.

Example 4
An organic TFT was produced in the same manner as in Example 3 except that the conductive polymer was not added to the layer forming material containing metal fine particles.

Example 5
An organic TFT was produced in the same manner as in Example 1 except that an aqueous dispersion of gold fine particles having an average particle diameter of 10 nm was used as the layer forming material containing metal fine particles.

Example 6
An organic TFT was produced in the same manner as in Example 3 using polythiophenes described in Examples of Japanese Patent Application Laid-Open No. 2003-268083 for the semiconductor layer. However, the heating temperature was 180 ° C.

Comparative Example 2
An organic TFT was produced in the same manner as in Example 6 except that the conductive polymer was not added to the layer forming material containing metal fine particles and no pressing was performed during heating.

Example 7
An organic TFT was produced in the same manner as in Example 6 except that the conductive polymer was not added to the layer forming material containing metal fine particles.

The carrier mobility (cm ² / V · s) in the saturation region of each organic TFT produced above is shown.

Example 1 0.015
Example 2 0.020
Example 3 0.035
Comparative Example 1 0.0018
Example 4 0.016
Example 5 0.055
Example 6 0.037
Comparative Example 2 0.0022
Example 7 0.0095
Thereby, according to the manufacturing method of this invention, it turns out that the organic TFT excellent in the semiconductor performance is obtained. It can also be seen that when metal fine particles and a conductive polymer are mixed, a further excellent effect can be obtained, and the average particle diameter of the metal fine particles is preferably 20 nm or less.

  According to the method for producing an organic thin film transistor of the present invention, an organic thin film transistor excellent in semiconductor performance such as durability and carrier mobility can be continuously formed on a flexible base. Further, by mixing the metal fine particles and the conductive polymer, the contact resistance is further reduced, and these effects can be particularly increased by using a π-conjugated material having liquid crystallinity at the time of thermoplasticity as a semiconductor material. .

Claims (11)

A layer containing a thermoplastic semiconductor material and a layer containing metal fine particles to be bonded to the layer are formed and heated after pressing or simultaneously pressed and heated to form a semiconductor layer, a source electrode, and a drain electrode. A method for manufacturing an organic thin film transistor. The method for producing an organic thin film transistor according to claim 1, wherein heating is performed at a temperature equal to or higher than a softening point of the thermoplastic semiconductor material. 2. The method for producing an organic thin film transistor according to claim 1, wherein the heating is performed at a temperature equal to or higher than a temperature at which the metal fine particles are thermally fused. 2. The method for producing an organic thin film transistor according to claim 1, wherein the average particle diameter of the metal fine particles is 20 nm or less. 2. The method of manufacturing an organic thin film transistor according to claim 1, wherein the layer containing metal fine particles contains a conductive polymer. The method for producing an organic thin film transistor according to claim 1, wherein the thermoplastic semiconductor material is a π-conjugated material. An organic thin film transistor manufactured by the manufacturing method according to claim 1. An organic thin film transistor, wherein a source electrode and a drain electrode are mixed with a semiconductor layer containing at least a part of a metal phase constituting the electrode and containing a thermoplastic semiconductor material, and bonded to the semiconductor layer. 9. The organic thin film transistor according to claim 8, wherein the metal phase is formed by thermally fusing metal fine particles. A plurality of organic thin film transistors connected via a gate bus line and a source bus line are formed on a support sheet, and the source electrode and the drain electrode of the thin film transistor are heated by at least a part of the metal phase constituting the electrode. An organic thin film transistor sheet, which is mixed with a semiconductor layer containing a plastic semiconductor material and bonded to the semiconductor layer. 11. The organic thin film transistor sheet according to claim 10, wherein the metal phase is formed by thermally fusing metal fine particles.

Images