JP2007067320A - Organic transistor and its manufacturing method, and organic transistor sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an organic transistor in which an organic semiconductor layer can easily and precisely be formed at a specified region without using a laser nor performing accurate alignment. <P>SOLUTION: The manufacturing method includes a stage of bringing into contact and heating a transferred body 11 which has a projection C1 on a substrate 1 and a transfer body 50 where at least the organic semiconductor layer 4 is formed, and transferring the organic semiconductor layer 4 only onto the projection C1 formed of one of an insulating layer, a gate insulating film 3, a source electrode 4, and a drain electrode 6. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic transistor, a manufacturing method thereof, and an organic transistor sheet, and more specifically, an organic transistor manufacturing method capable of easily and accurately forming an organic semiconductor layer at a predetermined site, and the organic transistor layer. The present invention relates to an organic transistor and an organic transistor sheet.

  With the development of information terminals in recent years, the development of mobile phones that can watch TV and portable displays is progressing. Moreover, like an organic EL display using a flexible substrate, it is possible to reduce the weight and make it flexible, and a large display that can be carried is being made. In addition to organic EL displays, research on electronic paper and the like has been actively conducted.

  As an image driving element for such a display, an active driving element constituted by a thin film TFT (transistor) is used. The thin film TFT is usually manufactured by forming a semiconductor thin film such as amorphous silicon (a-Si) or polycrystalline silicon (p-Si) on a glass substrate and forming other electrodes by vapor deposition or the like. The production of such a thin film TFT requires high-temperature processing, and it is difficult to use a flexible substrate such as a resin film as a substrate, and the manufacturing equipment and manufacturing cost are very high. .

  In recent years, organic TFTs using organic semiconductor materials have been actively studied. The formation of the organic semiconductor layer itself does not require a high temperature and has the advantage that it can be formed on a flexible substrate such as a resin film at room temperature. In addition, the organic semiconductor layer can be formed by a wet process such as printing or coating, and a flexible active driving element with low manufacturing equipment and low manufacturing cost can be manufactured.

  In the production of these organic TFTs, the patterning of the organic semiconductor layer is one of the important development issues. The patterning of the organic semiconductor material has been studied for application to the same patterning technique as the preceding organic EL display, that is, a direct or indirect pattern forming method such as a printing method, an ink jet method, or a transfer method.

For example, Patent Document 1 relates to patterning of an organic light emitting layer of an organic EL element. However, an organic light emitting layer is formed on a transfer body on which a convex pattern is formed, and the transfer body is pressure-bonded to a transfer target. There has been proposed a method of transferring an organic light-emitting layer having a predetermined pattern onto a transfer target by irradiating only a convex portion with a laser later. Patent Document 2 proposes a patterning method in which a photothermal conversion layer is formed in an organic TFT, and an organic semiconductor material is formed by heating and melting an organic semiconductor material provided at a laser-drawn portion.
JP 2000-12216 A JP 2004-146502 A

  By the way, in order to reduce the ON / OFF ratio of the current, the organic semiconductor layer is required to be as thin as about 100 nm like the organic light emitting layer of the organic EL element. Patterning is required. In order to form an organic light emitting layer thinly, a low-viscosity solution in which an organic semiconductor material is dissolved by several wt% must be used as a coating solution for forming an organic semiconductor layer. If impurities are included, it causes problems such as a decrease in charge mobility and device characteristics, so it is difficult to add a thickener or the like to the low-viscosity solution. It is difficult to form a fine pattern.

  In addition, regarding the formation of a direct fine pattern by the ink jet method, it is difficult to hold the droplets discharged from the ink jet head, and it is necessary to form a water-repellent partition wall for holding the droplets on the organic TFT substrate. There is a difficulty that there is. Also, matching between the ink jet head and the organic semiconductor material is necessary, and if the matching is poor, the organic semiconductor material droplets may not be ejected as intended, and as a result, defects may occur in the organic semiconductor layer. .

  In addition, the methods described in Patent Documents 1 and 2 both have a drawback in that the patterning accuracy depends on the operation accuracy of the stage, so that an expensive stage that moves with high accuracy and speed is required, and the equipment cost increases. .

  Moreover, it is necessary to perform accurate alignment in any of the printing method, the inkjet method, and the transfer method.

  The present invention has been made to solve the above-described problems, and its object is to easily and accurately form an organic semiconductor layer at a predetermined site without using a laser and without performing accurate alignment. Another object is to provide a method for manufacturing an organic transistor. Another object of the present invention is to provide an organic transistor and an organic transistor sheet produced by such a method.

  The present inventor has devised the shape of the gate insulating film at the site where the organic semiconductor layer is to be formed in the course of earnest research in order to solve the above problems, and a method for transferring the organic semiconductor layer to the site Thus, it has been found that an organic semiconductor layer can be easily and accurately formed at a predetermined site without using a laser and without performing accurate alignment, and this knowledge has been developed to complete the present invention. It was.

  That is, in the method for producing an organic transistor of the present invention, an object to be transferred having a convex portion on a substrate and a transfer body having at least an organic semiconductor layer are heated in close contact, and the organic transistor is formed only on the convex portion. Including a step of transferring a semiconductor layer, wherein the convex portion is formed of any one of an insulating layer, a gate insulating film, a source electrode, and a drain electrode.

  According to the present invention, a convex portion having good shape accuracy and positional accuracy is formed on the transfer target body, and the organic semiconductor layer formed on the transfer body is transferred by close contact heating only on the convex portion. The organic semiconductor layer can be easily and accurately formed at a predetermined site without using such a laser and without performing accurate alignment. Note that the convex portion may be formed of a gate insulating film, or formed of an insulating layer formed of an arbitrary insulating material, or an insulating layer partially including a source electrode and a drain electrode. There may be. A convex portion having good shape accuracy and position accuracy can be easily formed by applying a known lithography technique.

  The following four forms are mentioned as a preferable form of the manufacturing method of the organic transistor of the said invention.

  The organic transistor manufacturing method according to the first aspect of the present invention is a bottom gate / top contact structure manufacturing method, in which at least a gate electrode and a gate insulating film are formed in this order on a substrate. A step of preparing a transfer body in which the gate insulating film is a convex, a step of preparing a transfer body on which at least an organic semiconductor layer is formed, and heating the contact body and the transfer body in close contact with each other Then, the method includes a step of transferring the organic semiconductor layer only on the convex portion, and a step of forming a source electrode and a drain electrode on the transferred organic semiconductor layer.

  The method for producing an organic transistor according to the second embodiment of the present invention is a method for producing a bottom gate / bottom contact structure, in which at least a gate electrode, a gate insulating film, a source electrode and a drain electrode are formed on a substrate. A gate insulating film on the gate electrode has a convex portion, two small concave portions are formed in the convex portion, and a source electrode and a drain electrode are formed in each concave portion, respectively. A step of preparing a body, a step of preparing a transfer body on which at least an organic semiconductor layer is formed, and the transferred body and the transfer body are closely heated to form the source electrode and the drain electrode. And a step of transferring the organic semiconductor layer only on the convex portion.

  The method for producing an organic transistor according to the third embodiment of the present invention is a method for producing a top gate / top contact structure, in which at least an insulating layer is formed on a substrate, and the insulating layer forms a convex portion. A step of preparing a transfer body, a step of preparing a transfer body on which at least an organic semiconductor layer is formed, and the organic semiconductor layer only on the convex portion by closely heating the transfer body and the transfer body. A step of forming a source electrode and a drain electrode on the transferred organic semiconductor layer, and a step of forming at least a gate insulating film and a gate electrode in that order on the transferred organic semiconductor layer. And

  The method for producing an organic transistor according to the fourth embodiment of the present invention is a method for producing a top gate / bottom contact structure, in which at least a source electrode and a drain electrode are formed on a substrate. A step of preparing a transfer body in which an insulating layer is formed so as to fill a gap and forming a convex portion; a step of preparing a transfer body on which at least an organic semiconductor layer is formed; and A step of transferring the organic semiconductor layer only on the convex portion by closely heating the transfer body, and a step of forming at least a gate insulating film and a gate electrode in that order on the transfer body; .

  According to the inventions according to the first to fourth embodiments, a convex portion having good shape accuracy and positional accuracy is formed on the transfer target body, and the organic semiconductor layer formed on the transfer body is closely heated only on the convex portion. Therefore, the organic semiconductor layer can be easily formed (transferred) to a predetermined site without using a laser as in the prior art and without performing accurate alignment.

  In the method for manufacturing an organic transistor of the present invention, the transfer body is formed by forming at least a protective layer and an organic semiconductor layer in this order on a substrate.

  Conventionally, since the protective layer was formed after the organic semiconductor was formed, the organic semiconductor layer was easily damaged when the protective layer was formed, and the characteristics of the organic semiconductor layer were easily deteriorated. An organic semiconductor layer is formed on the organic semiconductor layer, and the organic semiconductor layer is transferred to the transfer target. Therefore, there is an advantage that conventional damage is not applied to the organic semiconductor layer. In addition, it can utilize as a transfer body of the manufacturing method of the said 1st-4th form by selecting layers other than an organic-semiconductor layer arbitrarily.

  In the method for producing an organic transistor according to the fourth aspect of the present invention, the transfer body is formed by forming at least a gate electrode, a gate insulating film, and an organic semiconductor layer in this order on a substrate. .

  According to the present invention, by forming a transfer body in which at least a gate electrode, a gate insulating film, and an organic semiconductor layer are formed in that order on a substrate, the organic semiconductor layer transfer step in the fourth embodiment, The insulating film and gate electrode forming step can be performed simultaneously with the transfer step.

  In the organic transistor manufacturing method of the present invention, the gate insulating film or insulating layer forming the convex portion is made of a cross-linkable resist material, and the gate insulating film or insulating layer is the gate electrode in the transferred object preparing step. It is characterized in that the resist material is applied and then pre-baked to form a pre-baked layer, and the pre-baked layer is post-baked after the transfer step.

  According to the present invention, since the gate insulating film or the insulating layer forming the convex portion is a pre-baked layer having adhesiveness during the transfer process, the organic semiconductor layer heated in close contact with the pre-baked layer is formed on the pre-baked layer. Easy to transfer. In the present application, the “pre-baked layer” means a resist film (a gate insulating film or an insulating layer) after pre-baking and before post-baking.

  The transfer body used in the method for producing the organic transistor of the present invention includes a sheet-like transfer body in which at least a substrate, a protective layer, and an organic semiconductor layer are formed in that order, or at least a substrate, a gate electrode, and a gate insulation. The substrate so that the organic semiconductor layer does not come into contact with any part other than the convex part when the sheet-like transfer body in which the film and the organic semiconductor layer are formed in that order is closely heated onto the transfer target having the convex part. That whose thickness is 3 micrometers or more is preferable. Thereby, when it adheres and heats on the to-be-transferred body which has a convex part, it can prevent that an organic-semiconductor layer contacts other than a convex part.

  An organic transistor according to the present invention for solving the above-described problems includes at least a gate electrode, an insulating layer (including a gate insulating film), an organic semiconductor layer, a source electrode, and the like, which are manufactured by the method for manufacturing an organic transistor of the present invention described above. In the organic transistor including a drain electrode, the organic semiconductor layer is formed on a convex portion including any one of an insulating layer, a gate insulating film, a source electrode, and a drain electrode.

  An organic transistor sheet of the present invention for solving the above problems is an organic transistor sheet in which the organic transistors produced by the above-described method for producing an organic transistor of the present invention are arranged in a matrix on a sheet-like substrate, The organic transistor includes at least a gate electrode, an insulating layer (including a gate insulating film), an organic semiconductor layer, a source electrode, and a drain electrode, and the organic semiconductor layer is any of the insulating layer, the gate insulating film, the source electrode, and the drain electrode. It is formed on the convex part of the same height which consists of these, or substantially the same height.

  According to the method for producing an organic transistor of the present invention, a convex portion having good shape accuracy and positional accuracy is formed on a transfer target, and the organic semiconductor layer formed on the transfer body is closely heated only on the convex portion for transfer. Therefore, the organic semiconductor layer can be easily and accurately formed at a predetermined site without using a laser as in the prior art and without performing accurate alignment. The convex portion can be easily formed with high shape accuracy and position accuracy by applying a well-known lithography technique. According to the manufacturing method of the present invention, it is possible to manufacture a flexible active drive element with low manufacturing equipment and low manufacturing cost. As a result, it can be used as an active drive element of a liquid crystal display device or an active drive element of an organic EL element.

  According to the organic transistor and the organic transistor sheet of the present invention, the organic semiconductor layer is formed on the convex portion having the same height or substantially the same height including any one of the insulating layer, the gate insulating film, the source electrode, and the drain electrode. Since it is formed by the method of the invention, it becomes a flexible active drive element mounting sheet in which the organic semiconductor layer is easily and accurately formed at a predetermined site, and the active drive element of the liquid crystal display device and the active drive element of the organic EL element Can be used as

  Hereinafter, an organic transistor of the present invention (hereinafter abbreviated as “organic TFT”), a manufacturing method thereof, and an organic TFT sheet will be described with reference to the drawings. In addition, this invention is not limited only to the content and embodiment of the following drawings.

(Organic TFT and manufacturing method thereof)
In the method for producing the organic TFT of the present invention, an object to be transferred having a convex portion on a substrate and a transfer body on which at least an organic semiconductor layer is formed are heated in close contact, and an organic semiconductor layer is formed only on the convex portion. Including a step of transferring, wherein the convex portion is formed of any one of an insulating layer, a gate insulating film, a source electrode, and a drain electrode.

  There are four types of organic TFT structures: bottom gate / top contact structure, bottom gate / bottom contact structure, top gate / top contact structure, and top gate / bottom contact structure. As shown in the following embodiments, the present invention can be applied to any structure. In the following, each layer constituting the organic TFT will be described mainly in the first embodiment, and in the second to fourth embodiments, differences will be mainly described.

(First embodiment)
FIG. 1 is a schematic cross-sectional view showing an example of an organic TFT having a bottom gate / top contact structure obtained by the method for manufacturing an organic TFT according to the first embodiment of the present invention, and FIG. It is process drawing which shows an example of the manufacturing method of the organic TFT concerning one Embodiment. As shown in FIG. 1, an organic TFT 10 having a bottom gate / top contact structure manufactured according to the present invention has a substrate 1, a gate electrode 2 formed on the substrate, and a gate electrode 2 on or on the gate electrode 2. A gate insulating film 3 formed so as to cover and at least on the gate electrode 2 has a convex portion (denoted by reference C1), an organic semiconductor layer 4 formed only on the convex portion C1, and an organic semiconductor layer 4 has a source electrode 5 and a drain electrode 6 formed separately from each other. Two types of protective layers are provided, one of which is a protective layer provided directly on the organic semiconductor layer 4, and the other is a protective layer provided to cover the entire organic TFT. 7b.

(substrate)
The substrate 1 can be selected from a wide range of materials as long as it is an insulating material. For example, an inorganic base material such as glass, silicon wafer or quartz, or polyamide, polyacetal, polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, or syndiotactic polystyrene, polyphenylene sulfide, polyether ether ketone, liquid crystal polymer, From fluorine resin, polyether nitrile, etc., polycarbonate, modified polyphenylene ether, polycyclohexene, polynorbornene resin, etc., or polysulfone, polyethersulfone, polyarylate, polyamideimide, polyetherimide, thermoplastic polyimide, etc. The organic base material which becomes, or those composite base materials can be mentioned.

  In particular, the use of a substrate made of a polymer compound is extremely useful because a lightweight and flexible organic TFT can be produced. In addition, when transparency is required, one having transparency can be selected from the above. The thickness of the substrate 1 applied in the present invention is usually selected from a range of about 25 μm to 1.5 mm in consideration of required flexibility and flexibility.

(Gate electrode)
The gate electrode 2 is formed on the substrate in the bottom gate / top contact structure. As the gate electrode 2, an electrode made of a metal or an inorganic material such as aluminum, titanium, or copper, an electrode formed using ink in which nanoparticles made of a conductive inorganic material are dispersed, or a conductive organic material such as polyaniline or polythiophene Or an electrode formed by applying a conductive ink. Such a gate electrode 2 may be formed as a single layer, or may be one in which the electrodes are laminated in a composite manner.

  Examples of metals or inorganic materials include metals such as aluminum, titanium, copper, gold, platinum, chromium, palladium, indium, molybdenum, nickel, alloys using these metals, polysilicon, amorphous silicon, tin oxide, indium oxide, An inorganic material such as indium / tin oxide (ITO) can be given. The gate electrode 2 made of the inorganic material can be formed by an existing thin film pattern forming means such as vapor deposition or sputtering. Specifically, the gate electrode 2 can be formed by using a mask film forming method or a photolithographic method. In addition, in an electrode formed using an ink in which nanoparticles made of a conductive inorganic material are dispersed, examples of the nanoparticles include conductive inorganic particles made of silver nanoparticles, gold nanoparticles, and the like. The ink in which such nanoparticles are dispersed becomes a conductive ink and has an advantage that it can be easily formed by a film forming means such as a coating method. In addition, there is an advantage that an electrode made of an organic material or conductive ink can be easily formed by a film forming means such as vapor deposition or coating. Furthermore, in the case of forming with a metal material, a metal colloid solution can be prepared, and the solution can be formed by various coating methods. However, in this case, as a base, a hydrophilic region and a hydrophobic region can be used. The hydrophilic / hydrophobic pattern formed by is preferable. Specific examples of the coating method include a spin coating method, a casting method, a pulling method, a transfer method, and an ink jet method.

  The thickness of the gate electrode 2 is preferably about 200 to 2000 nm, although it depends on the conductivity of the material. The lower limit of the thickness of the gate electrode 2 varies depending on the conductivity of the electrode material and the adhesion strength with the base substrate 1. The upper limit of the thickness of the gate electrode 2 is sufficient when the gate insulating film 3, the source electrode 5, and the drain electrode 6, which will be described later, are provided. In addition, it is necessary not to cause disconnection in the electrode pattern formed thereon. In particular, when the flexible substrate 1 is used, it is necessary to consider the balance of stress.

(Gate insulation film)
The gate insulating film 3 is formed on the gate electrode 2 in the bottom gate / top contact structure, and is made of inorganic materials such as SiO ₂ , SiN _x , A1 ₂ O ₃ , polychloropyrene, polyethylene terephthalate, polyoxymethylene, It can be formed from organic materials such as polyvinyl chloride, polyvinylidene fluoride, cyanoethyl pullulan, polymethyl methacrylate, polysulfone, polycarbonate, and polyimide, and commonly used resist materials. In particular, in the present invention, generally used resist materials can be preferably used from the viewpoint of production cost and ease of production, and screen printing methods, spin coating methods, casting methods, pulling methods, transfer methods, inkjet methods, and the like can be used. It can be formed into a predetermined pattern by a method or a photolithographic method. As commercially available resist materials, Nippon Steel Chemical's V259PA / PH5 (negative resist: cardo acrylic type), JSR's JNPC-48GL (negative resist: acrylic type material), Zeon Corporation's ZOP005 (thermosetting resist), ZERO4004 (positive resist) manufactured by Nippon Zeon Co., Ltd., novolac resin, etc. can be preferably used. The gate insulating film 3 made of the inorganic material can be formed using an existing pattern process such as a CVD method.

  The thickness of the gate insulating film 3 is preferably as thin as possible, but if it is too thin, the leakage current between the source / drain electrodes 5 and 6 and the gate electrode 2 increases, resulting in a device having a low ON / OFF ratio. Usually, it is preferably about 0.2 to 2.0 μm.

(Organic semiconductor layer)
The organic semiconductor layer 4 is formed on the convex portion C1 of the gate insulating film 3 in the bottom gate / top contact structure of the present invention. The organic semiconductor layer 4 is made of an organic semiconductor material. Specifically, various organic semiconductor materials represented by P3HT known as a P-type organic semiconductor material can be applied. In the present invention, as will be described later, since the organic semiconductor layer 4 is formed only on the convex portion C1, by forming the convex portion C1 with high accuracy, a laser is not used as in the prior art, and more accurately. The organic semiconductor layer 4 can be easily and accurately formed at a predetermined site without performing proper alignment. The organic semiconductor layer 4 is formed to a thickness of about 30 to 200 nm by dissolving an organic semiconductor material such as P3HT in a solvent and using a spin coating method, a casting method, a pulling method, or the like.

(Source electrode and drain electrode)
The source electrode 5 and the drain electrode 6 are preferably selected according to the type of organic semiconductor material. When a P-type organic semiconductor material is used, the source electrode 5 and the drain electrode 6 are usually formed of a metal having a high work function. When used, it is made of a metal having a small work function. This is because it is necessary to make ohmic contact with the organic semiconductor layer 14. The work function here is a potential difference necessary for taking out electrons in the solid to the outside, and is defined as an energy difference between the vacuum level and the Fermi level. As a preferable work function, the energy level of the HOMO (highest occupied orbit) of P3HT known as a P-type organic semiconductor material is 4.7 to 4.9 eV, so that it is close to 4.2 to 5.2 eV. It is desirable that the degree. Examples of electrode materials in such a range include gold, platinum, and transparent conductive films (indium / tin oxide, indium / zinc oxide, etc.), which are designed to have a channel length of 50 μm and a channel width of 1000 μm, for example. Using the mask thus formed, the film can be formed by a sputtering method or an electron beam (EB) evaporation method so as to have a film thickness of about 30 to 100 nm. In the case of forming with a metal material, it can also be formed by preparing a metal colloid solution and applying the solution by various coating methods. In this case, the base is a hydrophilic region and a hydrophobic region. The hydrophilic / hydrophobic pattern formed by is preferable.

  On the other hand, when using a P-type organic semiconductor material having an energy level of HOMO (highest occupied orbit) of about 3.0 eV, or an N-type organic semiconductor having an energy level of LUMO (lowest occupied orbit) of about 3.0 eV. In the case of using a material, it is preferable to form a film having a similar structure to aluminum having a work function of about 3.0 V, calcium, or lithium and aluminum.

  When the source electrode 5 and the drain electrode 6 are formed on the organic semiconductor layer 4 and the adhesion between the two is weak, the source electrode 5 and the drain electrode 6 are formed after the anchor layer is formed on the organic semiconductor layer. It is preferable. For example, when Au is used as the source electrode 5 and the drain electrode 6, adhesion can be improved by depositing about 5 nm of Cr as an anchor layer and then depositing Au.

(Interlayer insulation layer)
The organic TFT obtained in the present invention can be provided with an interlayer insulating layer as necessary. The interlayer insulating layer is preferably formed for the purpose of preventing contamination of the surface of the gate electrode 2 when the source electrode 5 and the drain electrode 6 are formed on the gate insulating film 3. Therefore, the interlayer insulating layer is formed on the gate insulating film 3 before forming the source electrode 5 and the drain electrode 6. Then, after the source electrode 5 and the drain electrode 6 are formed, the portion located above the channel region is processed to be completely removed or partially removed. It is desirable that the interlayer insulating layer region to be removed is equivalent to the size of the gate electrode 2. As the material of the interlayer insulating layer, inorganic materials such as SiO ₂ , SiN _x , Al ₂ O ₃ , polychloropyrene, polyethylene terephthalate, polyoxymethylene, polyvinyl chloride, polyvinylidene fluoride, cyanoethyl pullulan, polymethyl methacrylate, polysulfone, Examples thereof include organic materials such as polycarbonate and polyimide.

(Protective layer)
In the organic TFT obtained by the present invention, it is preferable that a protective layer mainly for the purpose of preventing oxidation of the organic semiconductor layer is formed. As shown in FIG. 1, there are two types of protective layers, a protective layer 7a provided directly on the organic semiconductor layer 4 and a protective layer 7b provided so as to cover the entire organic TFT structure. Such protective layers (7a, 7b) is a layer having an oxygen barrier property and water vapor barrier properties, can be, for example, the thickness 20~2000nm about thin film made of SiO _2, SiN, or the like. The protective layer can be formed by sputtering or the like.

(Production method of organic TFT)
The method for producing the organic TFT 10 according to the first embodiment is a method for producing a bottom gate / top contact structure as shown in FIG. 2, and at least a gate electrode 2 and a gate insulating film 3 are formed on the substrate 1 in this order. A step of preparing a transfer body 11 in which the gate insulating film 3 on the gate electrode 2 forms a convex portion C1, a step of preparing a transfer body 50 in which at least the organic semiconductor layer 4 is formed, A process of transferring the organic semiconductor layer 4 only on the convex portion C1 by closely heating the transfer body 11 and the transfer body 50, and a process of forming the source electrode 5 and the drain electrode 6 on the transferred organic semiconductor layer 4 And a step of forming a protective layer 7 covering them. Hereinafter, a description will be given based on the flowchart of FIG.

    First, as shown in FIG. 2A, a substrate 1 to be transferred on which a gate electrode 2 having a predetermined pattern is formed is prepared. The gate electrode 2 can be formed by a known film formation process and patterning process as described above.

  Next, the gate insulating film 3 is formed so that the gate insulating film 3 on the gate electrode 2 forms the convex portion C1. As a formation method of the gate insulating film 3, the method of FIG. 2 (B1) and the method of FIG. 2 (B2-1) (B2-2) can be mentioned. The method shown in FIG. 2B1 is a method in which the gate insulating film 3 is formed so as to cover the gate electrode 2 so that a convex portion C1 based on the thickness of the gate electrode 2 is formed on the gate electrode 2. . In this method, it is preferable that the gate electrode 2 is thick because a clear convex portion C1 can be formed. A preferable thickness is, for example, 100 nm or more.

  On the other hand, in the method of FIGS. 2B2-1 and B2-2, as a first step, the first gate insulating film 3a having the same thickness as the gate electrode 2 is formed and then slightly larger than the gate electrode 2. In this method, the convex portion C1 is formed by forming the second gate insulating film 3b having an area on the gate electrode 2. The convex portion C1 formed by this method has an advantage that it has a degree of freedom in design without depending on the thickness of the gate electrode 2 except for the difficulty that the number of steps increases because the gate insulating film is formed in two stages. .

  In this way, the transfer object 11 is prepared. In the transfer object 11, at least a gate electrode 2 and a gate insulating film 3 are formed in this order on a substrate 1, and the gate insulating film 3 on the gate electrode 2 forms a convex portion C1.

  Next, as shown in FIGS. 2C, 2 </ b> D, and 2 </ b> E, the prepared transfer body 11 and the transfer body 50 are closely heated to transfer the organic semiconductor layer 4 only onto the convex portion C <b> 1.

  The transfer body 50 only needs to have at least the organic semiconductor layer 4 formed thereon, but here, as shown in FIG. 9A, the protective layer 7a and the organic semiconductor layer 4 are formed on the transfer body substrate 51. A sheet-like transfer body 50 formed in order is used. The transfer substrate 51 can be the same as the transfer substrate 1 described above, but the organic semiconductor layer 4 other than the projection C1 when heated closely on the transfer body 11 having the projection C1. The thickness is preferably 3 μm or more so as not to contact the part. A release layer is preferably formed on the transfer substrate 51 so that the protective layer 7 a and the organic semiconductor layer 4 can be easily transferred to the transfer target 11. The material for forming the release layer is not particularly limited, and various commonly used materials can be used. For example, an acrylic resin layer having a thickness of about 0.1 to 10 μm is preferably used.

  Further, a primer layer for increasing the adhesiveness between the transfer body substrate 51 and the release layer is about 10 to 1000 nm in thickness so that the resin material forming such a release layer does not peel from the transfer body substrate 51. The transfer substrate may be used, or a transfer substrate that has been subjected to an easy adhesion process for improving the adhesion of the transfer substrate 51 itself may be used. The primer layer is arbitrarily selected depending on the type of transfer substrate and the type of release layer, and examples thereof include those formed of an acrylic or urethane resin. Examples of the substrate subjected to easy adhesion treatment include AD PP, which is an easy adhesion film manufactured by Toyo Cloth Co., Ltd., and Cosmo Shine A4300 and A7810 manufactured by Toyobo Co., Ltd.

  The close contact heating between the transfer body 50 and the transfer target 11 thus prepared is performed by, for example, press heating for pressing a heating plate from the substrate 51 side of the transfer body 50 or a roll for pressing a heating roll from the substrate 51 side of the transfer body 50. It can be performed by press heating or the like. The organic semiconductor layer 4 is transferred only onto the convex portion C1 by this contact heating. To ensure such transfer, the organic semiconductor layer 4 is separated when the transfer body 50 and the transfer target 11 are separated after the contact heating. The adhesion between the release layer (including the protective layer 7a) needs to be the smallest.

  As an example for that purpose, a method of forming the gate insulating film 2 forming the convex portion C1 with a crosslinkable resist material can be mentioned. That is, in the transferred object preparing step, a pre-baked layer is formed by applying a crosslinkable resist material on the gate electrode 2 and then performing pre-baking. Since this pre-baked layer has adhesiveness, when the transfer body 50 is heated in close contact with the pre-baked layer during the transfer step, the adhesion between the organic semiconductor layer 4 (including the protective layer 7a) and the pre-baked layer is It becomes larger than the adhesive force between the organic semiconductor layer 4 and the release layer, and the organic semiconductor layer 4 is easily transferred onto the pre-baked layer. The pre-baked layer is post-baked after the transfer process to form the gate insulating film 2. By such means, the organic semiconductor layer 4 can be transferred onto the pre-baked layer (gate insulating film 3) forming the convex portion C1. This example is merely an example, and the present invention is not limited to this means.

  As described above, as shown in FIG. 2E, the organic semiconductor layer 4 can be formed only on the gate insulating film 3 forming the convex portion C1.

  Next, as shown in FIG. 2 (F), a source electrode 5 and a drain electrode 6 are formed on the transferred organic semiconductor layer 4 to form an organic TFT, and then, as shown in FIG. 2 (G). Then, the protective layer 7b covering the entire organic TFT is formed to manufacture the organic TFT having the bottom gate / top contact structure according to the first embodiment of the present invention.

  In this manufacturing method, the convex portion C1 having good shape accuracy and positional accuracy is formed on the transfer target 11, and the organic semiconductor layer 4 formed on the transfer body 50 is transferred by close contact heating only on the convex portion C1. The organic semiconductor layer 4 can be easily and accurately formed at a predetermined site (only on the convex portion C1) without using a laser as in the prior art and without performing accurate alignment. In addition, since the convex part C1 with good shape accuracy and position accuracy can be easily formed by applying a well-known lithography technique, a new expensive manufacturing facility is unnecessary, which is advantageous in terms of manufacturing cost. .

(Second Embodiment)
FIG. 3 is a schematic cross-sectional view showing an example of an organic TFT having a bottom gate / bottom contact structure obtained by the organic TFT manufacturing method according to the second embodiment of the present invention. FIG. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 2 embodiment. As shown in FIG. 3, the organic TFT 20 having a bottom gate / bottom contact structure manufactured according to the present invention has a substrate 1, a gate electrode 2 formed on the substrate, and a gate electrode 2 on or on the gate electrode 2. It is formed so as to cover, and at least the gate electrode 2 has a convex portion (denoted by reference numeral C2), and two small concave portions 9, 9 are formed in the convex portion C2, and the source electrode is formed in the concave portions 9, 9. 5 and the drain electrode 6 are formed, and the organic semiconductor layer 4 is formed only on the convex portion C2. Two types of protective layers are provided, one of which is a protective layer provided directly on the organic semiconductor layer 4, and the other is a protective layer provided to cover the entire organic TFT. 7b.

  Further, as shown in FIG. 4, the manufacturing method of the organic TFT 20 according to the second embodiment is a manufacturing method of a bottom gate / bottom contact structure. At least the gate electrode 2, the gate insulating film 3, and the source electrode 5 are formed on the substrate 1. And the drain electrode 6 are formed, the gate insulating film 3 on the gate electrode 2 forms a convex portion C2, and two small concave portions 9, 9 are formed in the convex portion C2, and each concave portion 9, 9 is formed. A step of preparing a transfer body 21 in which the source electrode 5 and the drain electrode 6 are respectively formed, a step of preparing a transfer body 50 in which at least the organic semiconductor layer 4 is formed, a transfer body 21 and the transfer body 50 and a step of transferring the organic semiconductor layer 4 only onto the convex portion C2 where the source electrode 5 and the drain electrode 6 are formed, and a step of forming a protective layer 7 covering them. Have .

  Since each structure of the organic TFT shown in FIG. 3 obtained by the manufacturing method of the second embodiment is basically the same as that described in the first embodiment, the following is shown in FIG. The difference between the manufacturing process and the first embodiment will be mainly described, and the description of overlapping contents will be omitted.

  Since the steps of FIGS. 4A and 4B are the same as those in the first embodiment, description thereof is omitted. As shown in FIG. 4C, the prepared transfer target 21 has at least the gate electrode 2 and the gate insulating film 3 formed in that order on the substrate 1, and the gate insulating film 3 on the gate electrode 2. Forms a convex portion C2.

  Next, as shown in FIG. 4D, two small concave portions 9 are formed in the convex portion C2. The recesses 9 and 9 can be formed by known photolithography or the like, but since the source electrode 5 and the drain electrode 6 are filled in the recesses, the recesses 9 and 9 are formed at predetermined intervals. It is preferable.

  Next, as shown in FIG. 4E, the source electrode 5 and the drain electrode 6 are formed in the recesses 9 and 9, respectively. The source electrode 5 and the drain electrode 6 can be formed by the conventionally known methods described. The gate insulating film 3 on the gate electrode 2 formed by filling the concave portions 9 and 9 with the source electrode 5 and the drain electrode 6 forms a convex portion C2, and the organic semiconductor layer 4 is transferred onto the convex portion C4. Is done.

  As shown in FIGS. 4F, 4G, and 4H, the transfer of the organic semiconductor layer 4 onto the convex portion C2 is performed by closely heating the prepared transfer target 21 and the transfer member 50. As the transfer body, the same transfer body 50 as that in the first embodiment is used (see FIG. 9A), and the transfer is performed under the same conditions as those in the first embodiment. As described above, as shown in FIG. 4H, the organic TFT in which the organic semiconductor layer 4 is formed only on the gate insulating film 3 forming the convex portion C2 is configured.

  Next, as shown in FIG. 4I, a protective layer 7b that covers the entire organic TFT is formed to manufacture an organic TFT having a bottom gate / bottom contact structure according to the second embodiment of the present invention.

  In this manufacturing method, a convex portion C2 having good shape accuracy and positional accuracy is formed on the transfer target 21 in a form having the source electrode 5 and the drain electrode 6, and is formed on the transfer body 50 only on the convex portion C2. Since the organic semiconductor layer 4 is transferred by close contact heating, the organic semiconductor layer 4 is placed on a predetermined portion (only on the convex portion C2) without using a laser as in the prior art and without performing accurate alignment. It can be formed easily and accurately. The convex portion C2 having good shape accuracy and position accuracy can be easily formed by applying a well-known lithography technique, so that a new expensive manufacturing facility is unnecessary, which is advantageous in terms of manufacturing cost. .

(Third embodiment)
FIG. 5 is a schematic cross-sectional view showing an example of an organic TFT having a top-gate / top-contact structure obtained by the method for manufacturing an organic TFT according to the third embodiment of the present invention, and FIG. It is process drawing which shows an example of the manufacturing method of the organic TFT concerning 3 embodiment. As shown in FIG. 5, an organic TFT 30 having a top gate / top contact structure manufactured according to the present invention is formed on the substrate 1 and has an insulating portion formed on the substrate 1 and having a convex portion (denoted by reference numeral C3). Layer 8, organic semiconductor layer 4 formed only on convex portion C 3, source electrode 5 and drain electrode 6 formed on organic semiconductor layer 4, and so as to cover source electrode 5 and drain electrode 6. And the gate electrode 2 formed on the gate insulating film 3. Two types of protective layers are provided, one of which is a protective layer provided directly on the organic semiconductor layer 4, and the other is a protective layer provided to cover the entire organic TFT. 7b.

  In addition, as shown in FIG. 6, the method for producing the organic TFT 30 according to the third embodiment is a method for producing a top gate / top contact structure, in which at least an insulating layer 8 is formed on the substrate 1, and the insulating layer A step of preparing a transfer body 31 in which 8 forms a convex portion C3; a step of preparing a transfer body 50 on which at least the organic semiconductor layer 4 is formed; and the transfer body 31 and the transfer body 50 A step of heating and transferring the organic semiconductor layer 4 only on the convex portion C3, a step of forming the source electrode 5 and the drain electrode 6 on the transferred organic semiconductor layer 4, and the gate insulating film 3 so as to cover them , A step of forming the gate electrode 2 on the gate insulating film 3, and a step of forming a protective layer 7b covering the whole.

  Each configuration of the organic TFT shown in FIG. 5 obtained by the manufacturing method according to the third embodiment is basically the same as that described in the first embodiment, so that the following is shown in FIG. The difference between the manufacturing process and the first embodiment will be mainly described, and the description of overlapping contents will be omitted.

    First, as shown in FIG. 6A, a substrate 1 to be transferred on which an insulating layer 8 having a predetermined pattern is formed is prepared. As described above, the insulating film 8 formed here is preferably made of the same crosslinkable resist material as the gate insulating film 3 of the first embodiment. That is, a pre-baked layer is formed by applying a cross-linkable resist material on the substrate 1 and then performing pre-baking. Since this pre-baked layer has adhesiveness, when the transfer body 50 is heated in close contact with the pre-baked layer in the transfer step shown in FIGS. 6B, 6C, 6D, the organic semiconductor layer 4 (the protective layer 7a is also The adhesive strength between the organic semiconductor layer 4 and the release layer becomes larger, and the organic semiconductor layer 4 is easily transferred onto the prebaked layer. The pre-baked layer is post-baked after the transfer process to form the insulating layer 8. By such means, the organic semiconductor layer 4 can be transferred onto the pre-baked layer (insulating layer 8) forming the convex portion C3. This example is merely an example, and the present invention is not limited to this means. Further, the crosslinkable resist material can be easily formed into a predetermined pattern by a known film forming process and patterning process.

  Next, as shown in FIGS. 6B, 6 </ b> C, and 6 </ b> D, the prepared transfer body 31 and the transfer body 50 are heated in close contact to transfer the organic semiconductor layer 4 only onto the convex portion C <b> 3. As the transfer body, the same transfer body 50 as that in the first embodiment is used (see FIG. 9A), and the transfer is performed under the same conditions as those in the first embodiment. As described above, as shown in FIG. 6D, an organic TFT in which the organic semiconductor layer 4 is formed only on the insulating layer 8 forming the convex portion C3 is configured.

  Next, as illustrated in FIG. 6E, the source electrode 5 and the drain electrode 6 are formed over the organic semiconductor layer 4. The source electrode 5 and the drain electrode 6 can be formed by the conventionally known methods described.

Next, as illustrated in FIG. 6F, the gate insulating film 3 is formed so as to cover the organic semiconductor layer 4, the source electrode 5, and the drain electrode 6. The gate insulating film 3 in this step may be formed of a crosslinkable resist material as exemplified in the first and second embodiments, but it is necessary to perform transfer using adhesiveness as in the above embodiment. Therefore, a normal insulating film (for example, SiO ₂ ) may be used.

  Next, as shown in FIG. 6G, the gate electrode 2 is formed in a predetermined pattern over the gate insulating film 3. The gate electrode 2 can be formed by using the same photolithography or lift-off method as described above. Finally, as shown in FIG. 6H, a protective layer 7b covering the entire organic TFT is formed, and An organic TFT having a top gate / top contact structure according to the third embodiment is manufactured.

  In this manufacturing method, a convex portion C3 having good shape accuracy and positional accuracy is formed on the transfer body 31 with an insulating layer 8 such as a resist material, and the organic semiconductor layer 4 formed on the transfer body 50 only on the convex portion C3. Is transferred with close contact heating, so that the organic semiconductor layer 4 can be easily and accurately placed on a predetermined portion (only on the convex portion C3) without using a laser as in the prior art and without performing accurate alignment. Can be formed. The convex portion C3 having good shape accuracy and position accuracy can be easily formed by applying a well-known lithography technique, so that a new expensive manufacturing facility is unnecessary, which is advantageous in terms of manufacturing cost. .

(Fourth embodiment)
FIG. 7 is a schematic cross-sectional view showing an example of an organic TFT having a top gate / bottom contact structure obtained by the method for manufacturing an organic TFT according to the fourth embodiment of the present invention, and FIG. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 4 embodiment. As shown in FIG. 7, an organic TFT 40 having a top gate / bottom contact structure manufactured according to the present invention has a substrate 1 and a source electrode 5 and a drain electrode 6 formed on the substrate 1. A convex portion (indicated by reference numeral C4) formed with an insulating layer 8 so as to fill between the drain electrode 6 and the organic semiconductor layer 4 formed only on the convex portion C4; A gate insulating film 3 formed on the gate insulating film 3, a gate electrode 2 formed on the gate insulating film 3, and a protective layer 7b provided so as to cover the entire organic TFT.

  In addition, the organic TFT 40 according to the fourth embodiment is produced by a top gate / bottom contact structure as shown in FIG. 8, and at least the source electrode 5 and the drain electrode 6 are formed on the substrate 1. A step of preparing a transfer body 41 having an insulating layer 8 formed so as to fill between the source electrode 5 and the drain electrode 6 and forming a convex portion C4; and at least the organic semiconductor layer 4 is formed. A step of preparing the transfer body 60, a step of transferring the organic semiconductor layer 4 only onto the convex portion C4 by closely heating the transfer body 41 and the transfer body 60, and a gate insulating film 3 and a gate electrode thereon 2 in that order, and a step of forming a protective layer 7b covering the whole.

  Each configuration of the organic TFT shown in FIG. 7 obtained by the manufacturing method according to the fourth embodiment is basically the same as that described in the first embodiment, so that the following is shown in FIG. The difference between the manufacturing process and the first embodiment will be mainly described, and the description of overlapping contents will be omitted.

  In this embodiment, as shown in FIG. 8B, the transferred body 41 has a source electrode 5 and a drain electrode 6 formed on the substrate 1 and fills between the electrodes 5 and 6. The insulating layer 8 is formed in such a form, and they are integrated to form a convex portion (denoted by reference numeral C4).

  FIGS. 8A and 8B are an example of forming such a transferred body 41. For example, as shown in FIG. 8A, an insulating layer 8 having a predetermined pattern is formed on the substrate 1, and the insulating layer is formed. 8 can be obtained by opening portions where the source electrode 5 and the drain electrode 6 are to be formed by photolithography or the like, and then forming the source electrode 5 and the drain electrode 6 so as to fill the openings. On the other hand, although not shown, the source electrode 5 and the drain electrode 6 having a predetermined pattern are formed on the substrate 1, and the insulating layer 8 is formed so as to fill the opening between the source electrode 5 and the drain electrode 6. You can also. As described above, the insulating film 8 formed here is preferably made of the same crosslinkable resist material as the gate insulating film 3 of the first embodiment. That is, a pre-baked layer is formed by applying a cross-linkable resist material on the substrate 1 and then performing pre-baking. Since this pre-baked layer has adhesiveness, when the transfer body 60 is heated in close contact with the pre-baked layer in the transfer step shown in FIGS. 8C, 8D, and 8E, the organic semiconductor layer 4 and the pre-baked layer are separated. The adhesion force between them becomes larger than the adhesion force between the organic semiconductor layer 4 and the release layer, and the organic semiconductor layer 4 is easily transferred onto the pre-baked layer. The pre-baked layer is post-baked after the transfer process to form the insulating layer 8. By such means, the organic semiconductor layer 4 can be transferred onto the pre-baked layer (insulating layer 8) forming the convex portion C4. This example is merely an example, and the present invention is not limited to this means. Further, the crosslinkable resist material can be easily formed into a predetermined pattern by a known film forming process and patterning process.

  Next, as shown in FIGS. 8C, 8 </ b> D, and 8 </ b> E, the prepared transfer body 41 and the transfer body 60 are heated in close contact to form the organic semiconductor layer 4 and the gate insulating film only on the convex portion C <b> 4. 3 and the gate electrode 2 are integrally transferred so that they are laminated in that order.

As shown in FIG. 9B, the transfer body 60 includes a sheet-like transfer body 60 in which the gate electrode 2, the gate insulating film 3, and the organic semiconductor layer 4 are formed in this order on the transfer body substrate 51. Used. Since the transfer substrate 51 has been described in the first embodiment, a description thereof will be omitted. The gate insulating film 3 formed on the transfer body 60 may be formed of a cross-linkable resist material as exemplified in the first and second embodiments, but transfer using adhesiveness as in the above embodiment. Therefore, a normal insulating film (eg, SiO ₂ ) may be used. Further, a release layer is preferably formed on the transfer substrate 51 so that the gate electrode 2, the gate insulating film 3, and the organic semiconductor layer 4 can be integrally transferred to the transfer target 41. Since the release layer has been described in the first embodiment, the description thereof is omitted. If the gate electrode 2 is formed directly on the release layer, it may be difficult to release the gate electrode 2 from the release layer at the time of transfer. It is preferable to form the same layer (not shown) as the protective layer 7a shown in the embodiment. By forming such a layer (referred to as a protective layer) between the release layer and the gate electrode 2, it is easy to release between the release layer and the protective layer. The gate insulating film 3 and the organic semiconductor layer 4 can be transferred together. Further, since the transfer is performed under the same conditions as in the first embodiment, the description is omitted here. As described above, as shown in FIG. 8E, the organic semiconductor layer 4 and the like are formed only on the convex portion C4.

  Next, as shown in FIG. 8 (F), after patterning the gate electrode 2 to a predetermined size, finally, as shown in FIG. 8 (G), a protective layer 7b covering the entire organic TFT is formed. Thus, an organic TFT having a top gate / bottom contact structure according to the fourth embodiment of the present invention is manufactured.

  In this manufacturing method, a convex portion C4 having good shape accuracy and positional accuracy is formed on an object to be transferred 41 with an insulating layer, a source / drain electrode, and the like, and an organic semiconductor layer formed on the transfer body 60 only on the convex portion C4. 4 and the like are transferred by close heating, so that the organic semiconductor layer 4 can be easily placed on a predetermined portion (only on the convex portion C4) without using a laser as in the prior art and without performing accurate alignment. It can be formed with high accuracy. The convex portion C4 having good shape accuracy and position accuracy can be easily formed by applying a well-known lithography technique, so that a new expensive manufacturing facility is unnecessary, which is advantageous in terms of manufacturing cost. .

(Organic TFT sheet)
Next, although embodiment which forms the organic TFT obtained by the preparation method of the organic TFT of this invention on a sheet | seat is described, it is not limited by the following. The organic TFT sheet of the present invention is an organic TFT produced by the organic TFT production method of the present invention described above arranged in a matrix on a sheet-like substrate, and the organic TFT comprises at least a gate electrode and an insulating layer. (Including a gate insulating film), an organic semiconductor layer, a source electrode and a drain electrode, and the organic semiconductor layer is formed of any one of the insulating layer, the gate insulating film, the source electrode and the drain electrode. It is formed on the convex part.

  FIG. 10 is a schematic equivalent circuit diagram showing an example of the organic TFT sheet. The organic TFT sheet 80 has a large number of organic TFTs 81 arranged in a matrix, and gate bus lines 82 of gate electrodes and source bus lines 83 of source electrodes extend vertically and horizontally. An output element 84 is connected to the drain electrode of each organic TFT 81. The output element 84 is, for example, a liquid crystal display element or the like, and is shown by an equivalent circuit composed of a resistor and a capacitor 85. A region for each output element 84 constitutes a pixel of the display device. Reference numeral 86 denotes a horizontal drive circuit, and reference numeral 87 denotes a vertical drive circuit.

  FIG. 11 is a plan view showing the electrode arrangement of the organic TFT formed in one pixel and the formation site of the organic semiconductor layer with respect to the electrode arrangement. In FIG. 11, (a) is an aspect in which an electrode addition portion 6 a is provided on the drain electrode 6, (b) is an aspect in which an electrode addition portion 5 a is provided on the source electrode 5, and (c) is an illustration on the gate electrode 2. This is an aspect in which an electrode addition portion 2a is provided. The cross hatching in FIG. 11 is the formation part of the organic semiconductor layer 4 with respect to the electrode pattern composed of the gate electrode 2, the source electrode 5 and the drain electrode 6, and the organic semiconductor layer 4 includes the gate electrode 2, the source electrode 5 and the drain electrode. It is formed so as to overlap the three electrodes 6a in plan view. The formation site of the organic semiconductor layer 4 corresponds to the formation site of the convex portion to which the organic semiconductor layer 4 is transferred in the method for manufacturing the organic TFT of the present invention.

  FIG. 12 is a plan view showing an example of the formation site of the organic semiconductor layer when pixels having organic TFTs are arranged in a matrix. This figure is formed in the pattern shape of FIG. In the method for producing an organic TFT of the present invention, as described above, a convex portion having good shape accuracy and positional accuracy is formed on the transfer target, and the organic semiconductor layer 4 formed on the transfer body is formed only on the convex portion. Since the transfer is performed with close contact heating, the organic semiconductor layer 4 can be easily and accurately formed at a predetermined site without using a laser as in the prior art and without performing accurate alignment. As a result, it is possible to manufacture a flexible active drive element with low manufacturing equipment and low manufacturing costs. As a result, it can be used as an active drive element of a liquid crystal display device or an active drive element of an organic EL element.

  Hereinafter, the present invention will be described in more detail with reference to examples.

Example 1
Preparation of transfer object 11: A photosensitive resist for photolithography was formed on a substrate 1 made of a PET film having a thickness of 100 μm, and then Ti was formed by sputtering, followed by a lift-off method with a width of 50 μm and a thickness of 500 nm. Ti gate electrode 2 was formed. Next, a 20% solution (solvent: PEGMIA) of cardoacrylic negative resist material (V259PA / PH5 manufactured by Nippon Steel Chemical Co., Ltd.) is applied thereon by screen printing, followed by pre-baking and light irradiation at 90 ° C. for 30 minutes. Alkali development was performed and patterning was performed to form a pre-baked layer to be a gate insulating film. The pre-baked layer on the gate electrode 2 had the convex part C1 which protruded 200 nm in height from the pre-baked layer of the site | part in which the gate electrode 2 is not formed. Screen printing was performed using a screen plate of 500 lines and an emulsion thickness of 1.7 μm at a squeegee pressure of 0.176 Pa and a squeegee speed of 295 mm / sec.

  Preparation of transfer body 50: On a substrate 51 made of a PET film having a thickness of 75 μm, 20 wt% of PETA (pentaerythritol triacrylate), 2 wt% of Irgacure 184 (Ciba Specialty Chemicals Co., Ltd.) and a solvent (MEK: MIBK = 1: A release layer forming coating solution consisting of 1) was applied by die coating, and then UV irradiation was performed in a nitrogen atmosphere to form a release layer having a thickness of 0.9 μm. Thereafter, a protective layer-forming coating solution made of polyvinyl alcohol was applied on the release layer by die coating to form a protective layer 7a having a thickness of 200 nm. Furthermore, the organic-semiconductor-layer formation coating liquid was apply | coated on the protective layer 7a, and the 100-nm-thick organic-semiconductor layer 4 was formed. The organic semiconductor layer forming coating solution is obtained by dissolving 0.7 wt% of P3HT (regioregular type poly- (3-hexylthiophene)) in toluene. The organic semiconductor layer 4 is spin-coated on the release layer. A film was formed. In this way, a sheet-like transfer body 50 was produced.

Transfer: The obtained transfer body 50 is placed on the obtained transfer body 11, and the pre-baking of the transfer body 11 is performed by press heating under the conditions of pressure: 3 MPa / cm ² and temperature: 80 ° C. The organic semiconductor layer 4 and the protective layer 7a of the transfer body 50 were transferred only on the convex portion C1 of the layer. Thereafter, post-baking was performed at 220 ° C. for 30 minutes, and the pre-baked layer was used as the gate insulating film 3.

  Fabrication of organic TFT: The source electrode 5 and the drain electrode 6 are vapor-deposited with a thickness of about 250 nm using a mask designed to have a channel length of 50 μm and a channel width of 1000 μm (deposition rate is 0). 4 Å / s). Next, a protective layer 7b made of silicon nitride was formed so as to cover the whole by the CVD method. Thus, an organic TFT having a bottom gate / top contact structure according to the first embodiment of the present invention was produced.

(Example 2)
Fabrication of transfer target 21: After forming a photosensitive resist for photolithography on a substrate 1 made of a PET film having a thickness of 100 μm, Ti is formed by sputtering, and then by a lift-off method with a width of 50 μm and a thickness of 500 nm. Ti gate electrode 2 was formed. Next, a 20% solution of cardoacrylic negative resist material (V259PA / PH5 manufactured by Nippon Steel Chemical Co., Ltd.) (solvent: PEGMIA) is spin-coated to a thickness of 350 μm, and light irradiation and post-baking are performed. Cured. Thereafter, the same negative resist material as described above is spin-coated so as to have a thickness of 350 μm, followed by patterning by performing pre-baking at 90 ° C. for 30 minutes, light irradiation and alkali development, and forming a gate insulating film. Formed. The pre-baked layer on the gate electrode 2 has a convex portion C2 that protrudes 200 nm higher than the pre-baked layer at the portion where the gate electrode 2 is not formed. The convex portion C2 has a channel length of 50 μm and a channel width of 1000 μm. The recesses 9 and 9 having a depth of about 250 nm were formed by patterning (see FIG. 4D). Next, the recesses 9 and 9 were filled with gold by gold vapor deposition (0.4 Å / s) to form the source electrode 5 and the drain electrode 6. In this way, a transfer body 21 was produced.

Production and transfer of transfer body 50: As the transfer body 50, the same sheet-like transfer body 50 as in Example 1 was used. The transfer body 50 is placed on the transfer body 21 obtained as described above, and the pre-baking of the transfer body 21 is performed by pressing the transfer body 50 under pressure: 3 MPa / cm ² and temperature: 80 ° C. Only on the convex part C2 of the layer, the organic semiconductor layer 4 and the protective layer 7a of the transfer body 50 were transferred. Thereafter, post-baking was performed at 220 ° C. for 30 minutes, and the pre-baked layer was used as the gate insulating film 3.

  Fabrication of organic TFT: Finally, a protective layer 7b made of silicon nitride was formed so as to cover the whole by the CVD method, thereby fabricating a bottom gate / bottom contact organic TFT according to the second embodiment of the present invention.

(Example 3)
Production of Transferred Body 31: A cardo-acrylic negative resist material (V259PA / PH5 manufactured by Nippon Steel Chemical Co., Ltd.) 20% solution (solvent: PEGMIA) is 1 μm thick on a substrate 1 made of a PET film having a thickness of 100 μm. After spin coating as described above, prebaking at 90 ° C. for 30 minutes, light irradiation, and alkali development were performed for patterning to form a prebaked layer forming a convex portion C3 protruding 200 nm in height from the surface of the substrate 1.

Production and transfer of transfer body 50: As the transfer body 50, the same sheet-like transfer body 50 as in Example 1 was used. The transfer body 50 is placed on the transfer body 31 obtained as described above, and the pre-baking of the transfer body 31 is performed by press heating from above on the conditions of pressure: 3 MPa / cm ² and temperature: 80 ° C. Only on the convex part C3 of the layer, the organic semiconductor layer 4 and the protective layer 7a of the transfer body 50 were transferred. Thereafter, post baking was performed at 220 ° C. for 30 minutes, and the pre-baked layer was changed to the insulating layer 8.

  Fabrication of organic TFT: The source electrode 5 and the drain electrode 6 are vapor-deposited with a thickness of about 250 nm using a mask designed to have a channel length of 50 μm and a channel width of 1000 μm (deposition rate is 0). 4 Å / s). Next, an acrylic resin (JNPC-48GL: manufactured by JSR) was formed thereon with a thickness of 1 μm by spin coating, and was cured by irradiation with UV in a nitrogen atmosphere. Thereafter, Ti was formed into a film by sputtering under a condition using a mask, and then a Ti gate electrode 2 having a width of 50 μm and a thickness of 500 nm was formed by a lift-off method. Finally, a protective layer 7b made of silicon nitride was formed so as to cover the whole by the CVD method. Thus, an organic TFT having a top gate / top contact structure according to the third embodiment of the present invention was produced.

Example 4
Production of Transferred Material 41: Cardoacrylic negative resist material (V259PA / PH5 manufactured by Nippon Steel Chemical Co., Ltd.) 20% solution (solvent: PEGMIA) is 1 μm thick on a substrate 1 made of a PET film having a thickness of 100 μm. After spin coating as described above, patterning was performed by performing pre-baking at 90 ° C. for 30 minutes, light irradiation, and alkali development to form a pre-baked layer forming a convex portion C4 projecting 200 nm in height from the surface of the substrate 1. Next, after forming an opening in the pre-baked layer, gold deposition (0.4 Å / s) was performed, and the source electrode 5 and the drain electrode 6 were filled in the opening.

  Preparation of transfer body 60: On substrate 51 made of a PET film having a thickness of 75 μm, PETA (pentaerythritol triacrylate) 20 wt%, Irgacure 184 (Ciba Specialty Chemicals) 2 wt% and solvent (MEK: MIBK = 1: A release layer forming coating solution consisting of 1) was applied by die coating, and then UV irradiation was performed in a nitrogen atmosphere to form a release layer having a thickness of 0.9 μm. On the release layer, a coating solution for forming a protective layer made of polyvinyl alcohol is applied by die coating to form a protective layer (not shown) having a thickness of 200 nm, and then Ti having a thickness of 500 nm is sputtered to form a gate electrode. After the film 2 is formed, a 20% solution (solvent: PEGMIA) of cardoacrylic negative resist material (V259PA / PH5 manufactured by Nippon Steel Chemical Co., Ltd.) is applied by spin coating, and then post-baked at 220 ° C. for 30 minutes. A gate insulating film 3 was formed. Subsequently, an organic semiconductor layer 4 was formed by spin-coating a coating solution for forming an organic semiconductor layer in which 0.7 wt% of P3HT (regioregular type poly- (3-hexylthiophene)) was dissolved in toluene. In this way, a sheet-like transfer body 60 was produced.

Transfer: The obtained transfer body 60 is placed on the obtained transfer body 41, and the pre-baking of the transfer body 41 is performed by press-heating from above on the conditions of pressure: 3 MPa / cm ² and temperature: 80 ° C. Transfer was performed so that the organic semiconductor layer 4, the gate insulating film 3, the gate electrode 2, and the protective layer of the transfer body 60 were laminated in that order only on the convex portion C 4 of the layer.

  Preparation of organic TFT: After the transfer, post-baking at 220 ° C. for 30 minutes was performed, and the pre-baked layer formed on the transfer target 41 was changed to the insulating layer 8. Then, finally, a protective layer 7b made of silicon nitride was formed so as to cover the whole by the CVD method. Thereafter, the uppermost gate electrode 2 was changed to a gate electrode 2 having a width of 50 μm and a thickness of 500 nm, and finally a protective layer 7b made of silicon nitride was formed so as to cover the whole by a CVD method. Thus, an organic TFT having a top gate / bottom contact structure according to the fourth embodiment of the present invention was produced.

It is a schematic sectional drawing which shows an example of the organic TFT which consists of a bottom gate top contact structure obtained by the manufacturing method of the organic TFT which concerns on 1st Embodiment of this invention. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 1st Embodiment of this invention. FIG. 3 is a schematic cross-sectional view showing an example of an organic TFT having a bottom gate / bottom contact structure obtained by the method of manufacturing an organic TFT according to the second embodiment of the present invention. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 2nd Embodiment of this invention. It is a schematic sectional drawing which shows an example of the organic TFT which consists of a top-gate top contact structure obtained by the manufacturing method of the organic TFT which concerns on 3rd Embodiment of this invention. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 3rd Embodiment of this invention. FIG. 7 is a schematic cross-sectional view showing an example of an organic TFT having a top gate / bottom contact structure obtained by the organic TFT manufacturing method according to the fourth embodiment of the present invention. It is process drawing which shows an example of the manufacturing method of the organic TFT which concerns on 4th Embodiment of this invention. It is a schematic sectional drawing which shows the example of the sheet-like transfer body used by this invention. It is a schematic equivalent circuit diagram which shows an example of an organic TFT sheet. It is a top view which shows the convex part formation with respect to various electrode arrangement | positioning. It is a top view which shows an example of the formation site | part of the organic-semiconductor layer when the pixel which has organic TFT is arranged in matrix form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Gate electrode 3 Gate insulating film 4 Organic semiconductor layer 5 Source electrode 6 Drain electrode 7, 7a, 7b Protective layer 8 Insulating layer 9 Recess 10, 20, 30, 40 Organic TFT
11, 21, 31, 41 Transfer object 50, 60 Transfer object 80 Organic TFT sheet 81 Organic TFT
82 Gate bus line 83 Source bus line 84 Output element 85 Capacitor 86 Horizontal drive circuit 87 Vertical drive circuit 2a Electrode addition portion of gate electrode 5a Electrode addition portion of source electrode 6a Electrode addition portion of drain electrode

Claims (10)

  A step of transferring the organic semiconductor layer only on the convex portion by closely heating a transfer target having a convex portion on the substrate and a transfer body on which at least the organic semiconductor layer is formed; Is formed of any one of an insulating layer, a gate insulating film, a source electrode, and a drain electrode. A step of preparing a transfer body in which at least a gate electrode and a gate insulating film are formed in that order on a substrate, and the gate insulating film on the gate electrode forms a projection;
Preparing a transfer body having at least an organic semiconductor layer formed;
The step of transferring the organic semiconductor layer only on the convex portion by closely heating the transfer body and the transfer body; and
The method for producing an organic transistor according to claim 1, further comprising: forming a source electrode and a drain electrode on the transferred organic semiconductor layer. A transferred object in which at least a gate electrode, a gate insulating film, a source electrode, and a drain electrode are formed on a substrate, and the gate insulating film on the gate electrode forms a convex portion, and the convex portion is small. Preparing a transfer body in which two recesses are formed, and a source electrode and a drain electrode are respectively formed in each recess;
Preparing a transfer body having at least an organic semiconductor layer formed;
And a step of transferring the organic semiconductor layer only onto the convex portion on which the source electrode and the drain electrode are formed by heating the transfer target and the transfer member in close contact with each other. The manufacturing method of the organic transistor of Claim 1. A step of preparing a transfer body in which at least an insulating layer is formed on a substrate, and the insulating film forms a convex portion; and
Preparing a transfer body having at least an organic semiconductor layer formed;
The step of transferring the organic semiconductor layer only on the convex portion by closely heating the transfer body and the transfer body; and
Forming a source electrode and a drain electrode on the transferred organic semiconductor layer;
The method for producing an organic transistor according to claim 1, further comprising: forming at least a gate insulating film and a gate electrode in that order. Providing at least a source electrode and a drain electrode on a substrate, preparing an object to be transferred in which an insulating layer is formed so as to fill a space between the source electrode and the drain electrode, and forming a convex portion;
Preparing a transfer body having at least an organic semiconductor layer formed;
The step of transferring the organic semiconductor layer only on the convex portion by closely heating the transfer body and the transfer body; and
The method for producing an organic transistor according to claim 1, further comprising: forming at least a gate insulating film and a gate electrode in that order.   The method for producing an organic transistor according to claim 1, wherein the transfer body is formed by forming at least a protective layer and an organic semiconductor layer in that order on a substrate.   6. The method for producing an organic transistor according to claim 5, wherein the transfer body is formed by forming at least a gate electrode, a gate insulating film, and an organic semiconductor layer in this order on a substrate.   The gate insulating film or insulating layer forming the convex portion is made of a cross-linkable resist material, and the gate insulating film or insulating layer is pre-baked after the resist material is applied on the gate electrode in the transferred object preparing step. The method for producing an organic transistor according to claim 1, wherein a pre-baked layer is formed, and the pre-baked layer is post-baked after the transfer step.   An organic transistor comprising at least a gate electrode, an insulating layer (including a gate insulating film), an organic semiconductor layer, a source electrode, and a drain electrode, produced by the method for producing an organic transistor according to claim 1. An organic transistor, wherein the organic semiconductor layer is formed on a convex portion including any one of an insulating layer, a gate insulating film, a source electrode, and a drain electrode.   An organic transistor sheet in which the organic transistor produced by the method for producing an organic transistor according to claim 1 is arranged in a matrix on a sheet-like substrate, wherein the organic transistor comprises at least a gate electrode and an insulating material. A layer (including a gate insulating film), an organic semiconductor layer, a source electrode, and a drain electrode, and the organic semiconductor layer includes any one of the insulating layer, the gate insulating film, the source electrode, and the drain electrode. An organic transistor sheet formed on a convex portion having a height.

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