JP5087807B2 - Method for producing organic semiconductor element and composition for forming insulating film used therefor - Google Patents

Description

  The present invention relates to a method for producing an organic semiconductor element and an insulating film forming composition used therefor.

  In recent years, along with research on organic semiconductors, various organic field effect transistors (hereinafter referred to as organic FETs) using organic semiconductors have been proposed. Compared to thin film transistors (hereinafter referred to as TFTs) made of conventional amorphous silicon, polysilicon, or the like, it can be manufactured using a process at a low temperature and normal pressure, so that it has a flexible polymer support (hereinafter referred to as polymer). Application to a display or the like on which a TFT is formed is expected.

  Organic field-effect transistors (hereinafter referred to as organic FETs) use many thin films as semiconductors and are sometimes referred to as organic thin film transistors (hereinafter referred to as organic TFTs). The organic TFT includes a substrate, an insulating film, a gate electrode layer, a source electrode, a drain electrode, and an organic semiconductor film. As a material exhibiting semiconducting properties used for the organic semiconductor film, for example, a low molecular compound such as polyacene, a π-conjugated polymer such as polythiophene, and a π-conjugated oligomer are used.

  In an organic TFT using such a resin as a semiconductor film, when the gate voltage applied to the gate electrode layer is changed, the amount of charge at the interface between the insulating film and the organic semiconductor film becomes excessive or insufficient. As a result, the drain-source current value flowing from the source electrode to the organic semiconductor film changes to enable switching.

  The organic TFT has the same or better charge mobility than the amorphous silicon TFT, but has a very high driving voltage and threshold voltage. Accordingly, in the development of organic semiconductor elements, there is a demand for an organic insulator layer that can adjust the drive voltage and reduce the threshold voltage.

  When using a polymer base for the substrate, each component such as an organic insulator layer and a gate insulating film is at a temperature lower than the glass transition point of the polymer base in order to prevent the substrate from being softened or deteriorated, and It must be formed while avoiding vacuum.

In Patent Document 1, an insulating film containing a compound having a silsesquioxane structure is used. As a result, the organic insulating film can be formed at a low temperature. It is also possible to provide an organic semiconductor element that can be driven at a low voltage and has a stable driving voltage value.
JP 2004-304121 A

  However, in the insulating film disclosed in Patent Document 1, since all substituents of the silsesquioxane skeleton are inactive groups, voids are generated between molecules, and the insulating film is completely densified. It is not possible. For this reason, a large number of minute voids exist in the organic insulator layer, which causes problems such as an increase in leakage current and a decrease in durability.

In view of the above problems, an object of the present invention is to provide a method for producing an organic semiconductor element that can be driven at a low voltage and has a stable driving voltage value, and an insulating film forming composition used therefor.
A dense insulating film can be formed by using the composition for forming an insulating film of the present invention.

  The present inventors have found that by using a resin having a specific silsesquioxane skeleton, it is effective in reducing voids between molecules and has good electrical characteristics, and the present invention has been completed. It was.

［式中、Ｘは炭素数１〜１５のアルキレン基又は炭素数６〜１５の２価の芳香族炭化水素基を表し、Ｒ^１は水素原子又は炭素数１〜１５のアルキル基又は炭素数２〜１５のアルコキシアルキル基を表し、Ｒ^２は炭素数１〜４のアルキル基を表し、ｎは０又は１である。］ A first aspect of the present invention is an insulating film for forming an insulating film between a gate electrode layer and an organic semiconductor film layer of an organic semiconductor element, which contains a resin component (A) having a silsesquioxane skeleton. A composition for forming an insulating film, the resin component (A) comprising a silsesquioxane resin (A1) having a structural unit (a1) represented by the following general formula (a-1) It is.

[Wherein, X represents an alkylene group having 1 to 15 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R ¹ represents a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or 2 carbon atoms. Represents an alkoxyalkyl group having ˜15, R ² represents an alkyl group having 1 to 4 carbon atoms, and n is 0 or 1. ]

  According to a second aspect of the present invention, there is provided a step of forming an insulating film by applying the above-described composition for forming an insulating film on a substrate provided with a gate electrode layer, and forming an organic semiconductor film on the insulating film. And a step of forming a source electrode and a drain electrode on the organic semiconductor film.

  In the present invention, the “structural unit” refers to a monomer unit constituting a polymer. Further, “organic semiconductor film layer (hereinafter also referred to as organic semiconductor film)” and “insulating film” are intended to include a single thin film and a layered structure in which a plurality of thin films are stacked.

  According to the present invention, at least a part of the side chain of the resin (A) having a silsesquioxane skeleton has a hydroxyl group and / or a group obtained by substituting a hydrogen atom of this hydroxyl group with a hydrophobic group (a1). By doing so, it becomes possible to reduce voids between molecules. As a result, a dense insulating film can be formed. As a result, it is possible to provide an organic semiconductor element that can be driven at a low voltage and has a stable driving voltage value.

  Hereinafter, embodiments of the present invention will be described.

[Insulating film forming composition]
The composition for forming an insulating film according to the present invention generates a resin component (A) having a silsesquioxane skeleton (hereinafter also referred to as component (A)), preferably further generating an acid or a base by the action of light or heat. Compound (B) (hereinafter also referred to as component (B)). Each will be described below.

［式中、Ｘは炭素数１〜１５のアルキレン基又は炭素数６〜１５の２価の芳香族炭化水素基を表し、Ｒ^１は水素原子又は炭素数１〜１５のアルキル基又は炭素数２〜１５のアルコキシアルキル基を表し、Ｒ^２は炭素数１〜５のアルキレン基を表し、ｎは０又は１である。］ <(A) component>
(A) A component contains the silsesquioxane resin (A1) which has a structural unit (a1) represented by the following general formula (a-1).

[Wherein, X represents an alkylene group having 1 to 15 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R ¹ represents a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or 2 carbon atoms. Represents an alkoxyalkyl group having ˜15, R ² represents an alkylene group having 1 to 5 carbon atoms, and n is 0 or 1. ]

  X represents an alkylene group having 1 to 15 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms. Examples of the alkylene group having 1 to 15 carbon atoms include linear, branched and cyclic alkylene groups. The linear or branched alkylene group preferably has 1 to 6 carbon atoms and is hydrogen from a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a tert-butyl group, or the like. Examples include groups excluding one atom.

  In the case of a cyclic alkylene group, it is preferably 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples thereof include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing two or more hydrogen atoms from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

  The divalent aromatic hydrocarbon group having 6 to 15 carbon atoms is a group obtained by removing one hydrogen atom from a naphthyl group, phenyl group, anthracenyl group, phenanthryl group, etc., and removing one hydrogen atom from a phenyl group The groups are preferred.

R ¹ is an alkyl group having 1 to 15 carbon atoms or an alkoxyalkyl group having 2 to 15 carbon atoms. Examples of the alkyl group having 1 to 15 carbon atoms include linear, branched and cyclic alkyl groups. The linear or branched alkyl group preferably has 1 to 6 carbon atoms, and is a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, tert-butyl, tert-amyl. Groups and the like.

  In the case of a cyclic alkyl group, the alkyl group preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one hydrogen atom from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane. Among these, 2-methyl-2-adamantyl group, 2-ethyl-2-adamantyl group, 1-methyl-1-cyclohexyl group, 1-methyl-1-cyclopentyl group, 1-ethyl-1-cyclohexyl group, 1 -Ethyl-1-cyclopentyl group etc. are mentioned.

  Examples of the alkoxyalkyl group having 2 to 15 carbon atoms include 1-ethoxyethyl group, 1-ethoxymethyl group, 1-methoxyethyl group, 1-methoxymethyl group, 1-methoxypropyl group, 1-ethoxypropyl group, 1-ethoxypropyl group, An n-butoxyethyl group, a 2-adamantoxymethyl group, a 1-cyclohexyloxymethyl group and the like can be mentioned.

R ² is an alkylene group having 1 to 5 carbon atoms, and is a hydrogen atom 1 from a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a tert-butyl group, a tert-amyl group, or the like. Examples include groups other than individual groups.

  n is 0 or 1, and is preferably 1. However, n is 0 when X is a linear or branched alkylene group.

  The structural unit (a1) is 10 to 95 mol%, preferably 15 to 90 mol%, more preferably 20 to 85 mol%, based on all structural units constituting the silsesquioxane resin (A1). 30 to 80 mol% is most preferable. By setting it as the said range, it is excellent in the effect of this invention.

  The silsesquioxane skeleton has a ladder structure in which an inorganic compound and an organic compound are hybridized because the main chain is a siloxane unit and the side chain is a hydrocarbon group. Since this ladder structure has few branches, there are fewer intermolecular voids than a resin having a normal silsesquioxane skeleton. Therefore, by having a silsesquioxane skeleton, a dense insulating film can be formed even at a low temperature. Further, even when the film thickness is 500 nm or less, an insulating film having sufficient insulating properties can be formed.

However, because of the ladder structure, there are inevitably generated voids between molecules. According to the present invention, since the structural unit (a1) represented by the general formula (a-1) is used, the group represented by R ¹ in the structural unit (a1) serves as a reactive site, and an insulating film is formed. It becomes possible to fill the gaps between the molecules that occur during the process. As a result, a denser insulating film can be formed than a resin having no reaction active site.

［式中、Ｒ^３は炭素数１〜１５のアルキル基又は炭素数６〜１５の芳香族炭化水素基を表す。］ The component (A) may further contain a structural unit (a2) represented by the following general formula (a-2).

[Wherein R ³ represents an alkyl group having 1 to 15 carbon atoms or an aromatic hydrocarbon group having 6 to 15 carbon atoms. ]

R ³ represents an alkyl group having 1 to 15 carbon atoms or an aromatic hydrocarbon group having 6 to 15 carbon atoms. Examples of the alkyl group having 1 to 15 carbon atoms include linear, branched and cyclic alkyl groups. The linear or branched alkyl group preferably has 1 to 6 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and a tert-butyl group. It is done.

  In the case of a cyclic alkyl group, the alkyl group preferably has 4 to 15 carbon atoms, more preferably 4 to 12 carbon atoms, and most preferably 5 to 10 carbon atoms. Specific examples include groups in which two or more hydrogen atoms have been removed from a polycycloalkane such as monocycloalkane, bicycloalkane, tricycloalkane, and tetracycloalkane. Specific examples include monocycloalkanes such as cyclopentane and cyclohexane, and groups obtained by removing one hydrogen atom from polycycloalkanes such as adamantane, norbornane, isobornane, tricyclodecane, and tetracyclododecane.

  Examples of the aromatic hydrocarbon group include a naphthyl group, a phenyl group, an anthracenyl group, a phenanthryl group, and a benzyl group, and a phenyl group or a benzyl group is preferable.

  The structural unit (a2) is preferably 5 to 50 mol%, more preferably 10 to 40 mol%, more preferably 15 to 30 mol, based on all structural units constituting the silsesquioxane resin (A1). % Is most preferred. By setting it as the said range, it is excellent in the effect of this invention.

  By further containing this structural unit (a2), it is possible to control the reactivity of the structural unit (a1) and to impart an appropriate reactivity to the extent that it is possible to reduce the voids between molecules. Become.

The silsesquioxane resin (A1) may be a random polymer in which the structural unit (a1) and the structural unit (a2) are randomly polymerized, or may be a block polymer. Moreover, not only a binary polymer but a ternary polymer and a quaternary polymer may be sufficient. Specifically, at least one selected from the following structural formulas (A-1) to (A-7) is preferably included.

  The mass average molecular weight (Mw) of the silsesquioxane resin (A1) is not particularly limited, but is preferably 1000 or more and 10,000 or less, and more preferably 2000 or more and 10,000 or less. By setting it within the above range, the solubility in an organic solvent is good.

  The component (A) according to the present invention can be produced by the method disclosed in WO2004 / 055598 or WO2004 / 051376.

<(B) component>
The composition for forming an insulating film according to the present invention further contains a compound (B) that generates an acid or a base by the action of light or heat (hereinafter also referred to as component (B)). By further containing the component (B), the hydrolysis reaction in the component (A) is promoted, and the silsesquioxane compound is efficiently crosslinked in a ladder shape. As a result, it is possible to efficiently fill the gaps between molecules generated when the insulating film is formed. As a result, a denser insulating film can be formed than a resin having no reaction active point.

Here, the “compound that generates an acid or a base by the action of heat” refers to a compound that generates an acid or a base by heating at 80 ° C. or higher and 200 ° C. or lower.
The “compound that generates an acid or a base by the action of light” refers to a compound that generates an acid or a base by irradiation with ultraviolet rays.
Here, a compound that generates an acid by the action of heat is referred to as a thermal acid generator.
Here, a compound that generates a base by the action of heat is referred to as a thermal base generator.
Here, a compound that generates an acid by the action of light is called a photoacid generator.
Here, a compound that generates a base by the action of light is called a photobase generator.
The component (B) of the present invention preferably contains at least one selected from the group consisting of a thermal acid generator, a thermal base generator, a photoacid generator, and a photobase generator.

The thermal acid generator used in the present invention is a compound that generates an acid in response to heat. The thermal acid generator is not particularly limited, but 2,4,4,6-tetrabromocyclohexadienone, benzoin tosylate, 2-nitrobenzyl tosylate, other alkyl esters of organic sulfonic acid, etc. Can be used. Specific examples include sulfonium salts, iodonium salts, benzothiazonium salts, ammonium salts, onium salts such as phosphonium salts, and the like. Of these, iodonium salts, sulfonium salts, and benzothiazonium salts are particularly preferable. Specific examples of the sulfonium salt and the benzothiazonium salt include, for example, 4-acetoxyphenyldimethylsulfonium hexafluoroarsenate, benzyl-4-hydroxyphenylmethylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylmethylsulfonium hexafluoroantimony Nate, dibenzyl-4-hydroxyphenylsulfonium hexafluoroantimonate, 4-acetoxyphenylbenzylsulfonium hexafluoroantimonate, 3-benzylbenzothiazolium hexafluoroantimonate, a compound represented by the following chemical formula (B-1), etc. Is mentioned.

  The thermal base generator used in the present invention is a compound that generates a base in response to heat. The thermal base generator is not particularly limited, but carbamate derivatives such as 1-methyl-1- (4-biphenylyl) ethyl carbamate and 1,1-dimethyl-2-cyanoethyl carbamate, urea and N, Urea derivatives such as N-dimethyl-N′-methylurea, dihydropyridine derivatives such as 1,4-dihydronicotinamide, quaternized ammonium salts of organic silane and organic borane, dicyandiamide and the like are used. In addition, guanidine trichloroacetate, methylguanidine trichloroacetate, potassium trichloroacetate, guanidine phenylsulfonylacetate, guanidine p-chlorophenylsulfonylacetate, guanidine p-methanesulfonylphenylsulfonylacetate, potassium phenylpropiolate, guanidine phenylpropiolate, phenylpropiolic acid Examples include cesium, guanidine p-chlorophenylpropiolate, guanidine p-phenylene-bis-phenylpropiolate, tetramethylammonium phenylsulfonylacetate, and tetramethylammonium phenylpropiolate.

  The photoacid generator used in the present invention is a compound that generates an acid in response to light. The photoacid generator is not particularly limited, but onium salts, diazomethane derivatives, glyoxime derivatives, bissulfone derivatives, β-ketosulfone derivatives, disulfone derivatives, nitrobenzyl sulfonate derivatives, sulfonate ester derivatives, N-hydroxyimides Known acid generators such as sulfonic acid ester derivatives of compounds can be used.

  Specific examples of the onium salt include tetramethylammonium trifluoromethanesulfonate, tetramethylammonium nonafluorobutanesulfonate, tetra-n-butylammonium nonafluorobutanesulfonate, tetraphenylammonium nonafluorobutanesulfonate, p -Toluenesulfonic acid tetramethylammonium, trifluoromethanesulfonic acid diphenyliodonium, trifluoromethanesulfonic acid (p-tert-butoxyphenyl) phenyliodonium, p-toluenesulfonic acid diphenyliodonium, p-toluenesulfonic acid (p-tert-butoxyphenyl) ) Phenyliodonium, trifluoromethanesulfonic acid triphenylsulfonium, trifluoromethanesulfonic acid (p-tert-butyl) Xylphenyl) diphenylsulfonium, bis (p-tert-butoxyphenyl) phenylsulfonium trifluoromethanesulfonate, tris (p-tert-butoxyphenyl) sulfonium trifluoromethanesulfonate, triphenylsulfonium p-toluenesulfonate, p-toluenesulfonic acid (P-tert-butoxyphenyl) diphenylsulfonium, p-toluenesulfonic acid bis (p-tert-butoxyphenyl) phenylsulfonium, p-toluenesulfonic acid tris (p-tert-butoxyphenyl) sulfonium, nonafluorobutanesulfonic acid tri Phenylsulfonium, butanesulfonic acid triphenylsulfonium, trifluoromethanesulfonic acid trimethylsulfonium, p-toluenesulfonic acid Limethylsulfonium, cyclohexylmethyl trifluoromethanesulfonate (2-oxocyclohexyl) sulfonium, cyclohexylmethyl p-toluenesulfonate (2-oxocyclohexyl) sulfonium, dimethylphenylsulfonium trifluoromethanesulfonate, dimethylphenylsulfonium p-toluenesulfonate, Dicyclohexylphenylsulfonium trifluoromethanesulfonate, dicyclohexylphenylsulfonium p-toluenesulfonate, trinaphthylsulfonium trifluoromethanesulfonate, cyclohexylmethyl (2-oxocyclohexyl) sulfonium trifluoromethanesulfonate, (2-norbornyl) methyl trifluoromethanesulfonate ( 2-Oxocyclohexyl) sulfoniu And ethylene bis [methyl (2-oxocyclopentyl) sulfonium trifluoromethanesulfonate], 1,2'-naphthylcarbonylmethyltetrahydrothiophenium triflate, and the like.

  Examples of the diazomethane derivative include bis (benzenesulfonyl) diazomethane, bis (p-toluenesulfonyl) diazomethane, bis (xylenesulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, bis (cyclopentylsulfonyl) diazomethane, and bis (n-butylsulfonyl). Diazomethane, bis (isobutylsulfonyl) diazomethane, bis (sec-butylsulfonyl) diazomethane, bis (n-propylsulfonyl) diazomethane, bis (isopropylsulfonyl) diazomethane, bis (tert-butylsulfonyl) diazomethane, bis (n-amylsulfonyl) Diazomethane, bis (isoamylsulfonyl) diazomethane, bis (sec-amylsulfonyl) diazomethane, bis (tert-amyl) Sulfonyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-butylsulfonyl) diazomethane, 1-cyclohexylsulfonyl-1- (tert-amylsulfonyl) diazomethane, 1-tert-amylsulfonyl-1- (tert-butylsulfonyl) diazomethane Etc.

  Examples of the glyoxime derivative include bis-O- (p-toluenesulfonyl) -α-dimethylglyoxime, bis-O- (p-toluenesulfonyl) -α-diphenylglyoxime, bis-O- (p-toluenesulfonyl). -Α-dicyclohexylglyoxime, bis-O- (p-toluenesulfonyl) -2,3-pentanedione glyoxime, bis-O- (p-toluenesulfonyl) -2-methyl-3,4-pentanedione glyoxime Bis-O- (n-butanesulfonyl) -α-dimethylglyoxime, bis-O- (n-butanesulfonyl) -α-diphenylglyoxime, bis-O- (n-butanesulfonyl) -α-dicyclohexylglyme Oxime, bis-O- (n-butanesulfonyl) -2,3-pentanedione glyoxime, bis-O (N-butanesulfonyl) -2-methyl-3,4-pentanedione glyoxime, bis-O- (methanesulfonyl) -α-dimethylglyoxime, bis-O- (trifluoromethanesulfonyl) -α-dimethylglyoxime Bis-O- (1,1,1-trifluoroethanesulfonyl) -α-dimethylglyoxime, bis-O- (tert-butanesulfonyl) -α-dimethylglyoxime, bis-O- (perfluorooctanesulfonyl) ) -Α-dimethylglyoxime, bis-O- (cyclohexanesulfonyl) -α-dimethylglyoxime, bis-O- (benzenesulfonyl) -α-dimethylglyoxime, bis-O- (p-fluorobenzenesulfonyl)- α-dimethylglyoxime, bis-O- (p-tert-butylbenzenesulfonate )-.Alpha.-dimethylglyoxime, bis -O- (xylene sulfonyl)-.alpha.-dimethylglyoxime, bis -O- (camphorsulfonyl)-.alpha.-dimethylglyoxime, and the like.

  Examples of the bissulfone derivatives include bisnaphthylsulfonylmethane, bistrifluoromethylsulfonylmethane, bismethylsulfonylmethane, bisethylsulfonylmethane, bispropylsulfonylmethane, bisisopropylsulfonylmethane, bis-p-toluenesulfonylmethane, and bisbenzenesulfonylmethane. Is mentioned.

  Examples of the β-ketosulfone derivative include 2-cyclohexylcarbonyl-2- (p-toluenesulfonyl) propane, 2-isopropylcarbonyl-2- (p-toluenesulfonyl) propane, and the like.

  Examples of the disulfone derivatives include disulfone derivatives such as diphenyl disulfone derivatives and dicyclohexyl disulfone derivatives.

  Examples of the nitrobenzyl sulfonate derivative include nitrobenzyl sulfonate derivatives such as 2,6-dinitrobenzyl p-toluenesulfonate and 2,4-dinitrobenzyl p-toluenesulfonate.

  Examples of the sulfonic acid ester derivatives include 1,2,3-tris (methanesulfonyloxy) benzene, 1,2,3-tris (trifluoromethanesulfonyloxy) benzene, 1,2,3-tris (p-toluenesulfonyloxy). ) Sulphonic acid ester derivatives such as benzene.

  Examples of the sulfonate derivative of the N-hydroxyimide compound include N-hydroxysuccinimide methanesulfonate, N-hydroxysuccinimide trifluoromethanesulfonate, N-hydroxysuccinimide ethanesulfonate, N-hydroxysuccinimide 1-propanesulfone. Acid ester, N-hydroxysuccinimide 2-propanesulfonic acid ester, N-hydroxysuccinimide 1-pentanesulfonic acid ester, N-hydroxysuccinimide 1-octanesulfonic acid ester, N-hydroxysuccinimide p-toluenesulfonic acid ester, N-hydroxy Succinimide p-methoxybenzenesulfonic acid ester, N-hydroxysuccinimide 2-chloroethanesulfonic acid ester N-hydroxysuccinimide benzenesulfonic acid ester, N-hydroxysuccinimide 2,4,6-trimethylbenzenesulfonic acid ester, N-hydroxysuccinimide 1-naphthalenesulfonic acid ester, N-hydroxysuccinimide 2-naphthalenesulfonic acid ester, N -Hydroxy-2-phenylsuccinimide methanesulfonate, N-hydroxymaleimide methanesulfonate, N-hydroxymaleimide ethanesulfonate, N-hydroxy-2-phenylmaleimide methanesulfonate, N-hydroxyglutarimide methanesulfone Acid ester, N-hydroxyglutarimide benzenesulfonic acid ester, N-hydroxyphthalimide methanesulfonic acid ester, N-hydride Xylphthalimidobenzene sulfonate, N-hydroxyphthalimide trifluoromethanesulfonate, N-hydroxyphthalimide p-toluenesulfonate, N-hydroxynaphthalimide methanesulfonate, N-hydroxynaphthalimide benzenesulfonate, N- Hydroxy-5-norbornene-2,3-dicarboximide methanesulfonate, N-hydroxy-5-norbornene-2,3-dicarboximide trifluoromethanesulfonate, N-hydroxy-5-norbornene-2,3 -Dicarboximide p-toluenesulfonic acid ester etc. are mentioned.

  The photobase generator used in the present invention is a compound that generates a base in response to light. The photobase generator is not particularly limited, and examples thereof include photoactive carbamates such as triphenylmethanol, benzylcarbamate and benzoincarbamate; O-carbamoylhydroxylamide, O-carbamoyloxime, aromatic sulfonamide, Examples include amides such as alpha lactam and N- (2-allylethynyl) amide and other amides; oxime esters, α-aminoacetophenone, cobalt complexes, and the like. Of these, 2-nitrobenzylcyclohexylcarbamate, triphenylmethanol, o-carbamoylhydroxylamide, o-carbamoyloxime, [[(2,6-dinitrobenzyl) oxy] carbonyl] cyclohexylamine, bis [[(2-nitrobenzyl ) Oxy] carbonyl] hexane 1,6-diamine, 4- (methylthiobenzoyl) -1-methyl-1-morpholinoethane, (4-morpholinobenzoyl) -1-benzyl-1-dimethylaminopropane, N- (2- Preferred examples include nitrobenzyloxycarbonyl) pyrrolidine, hexaamminecobalt (III) tris (triphenylmethylborate), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone and the like.

Among these, it is preferable to use a thermal acid generator, more preferably an iodonium salt or a sulfonium salt, and a compound represented by the chemical formula (B-1) and the following chemical formula (B-2) is preferable.

  (B) As for content of a component, 0.5-30 mass parts is preferable with respect to 100 mass parts of (A) component, 0.5-25 mass parts is more preferable, 0.5-20 mass parts is the most. preferable. When the content exceeds 0.5 parts by mass, the crosslinking formation proceeds sufficiently and a good insulating film can be formed. When the content is less than 30 parts by mass, the storage stability of the composition for forming an insulating film can be kept good, and deterioration of the formed insulating film over time is suppressed.

<(C) component>
The composition for insulating film formation which concerns on this invention can further contain (C) component which is a crosslinking agent component. The component (C) is not particularly limited as long as it can react with the —OR ¹ group in the structural unit (a1). By further containing the component (B), the hydrolysis reaction in the component (A) is promoted, and the structural units (a1) and (a2) of the silsesquioxane compound are efficiently crosslinked in a ladder shape. As a result, it is possible to efficiently fill the gaps between molecules generated when the insulating film is formed. As a result, a denser insulating film can be formed than a resin having no reaction active point.

  The component (C) is not particularly limited and can be arbitrarily selected from known crosslinking agents.

  Specifically, 2,3-dihydroxy-5-hydroxymethylnorbornane, 2-hydroxy-5,6-bis (hydroxymethyl) norbornane, cyclohexanedimethanol, 3,4,8 (or 9) -trihydroxytricyclo Aliphatic cyclic carbonization having a hydroxyl group such as decane, 2-methyl-2-adamantanol, 1,4-dioxane-2,3-diol, 1,3,5-trihydroxycyclohexane, or a hydroxyalkyl group or both Examples thereof include hydrogen or an oxygen-containing derivative thereof.

  In addition, amino group-containing compounds such as melamine, acetoguanamine, benzoguanamine, urea, ethylene urea, propylene urea, glycoluril are reacted with formaldehyde or formaldehyde and lower alcohol, and the hydrogen atom of the amino group is hydroxymethyl group or lower alkoxymethyl group And a compound substituted with.

  Of these, those using melamine are melamine-based crosslinking agents, those using urea are urea-based crosslinking agents, those using alkylene ureas such as ethylene urea and propylene urea are alkylene urea-based crosslinking agents, and glycoluril is used. This was called a glycoluril-based crosslinking agent. The component (C) is at least one selected from the group consisting of melamine crosslinking agents, urea crosslinking agents, alkylene urea crosslinking agents, epoxy crosslinking agents, oxetane crosslinking agents, and glycoluril crosslinking agents. In particular, it is preferable to use a melamine crosslinking agent or an epoxy crosslinking agent.

Melamine-based crosslinking agents include compounds in which melamine and formaldehyde are reacted to replace the amino group hydrogen atom with a hydroxymethyl group, and melamine, formaldehyde and lower alcohol are reacted to convert the amino group hydrogen atom into a lower alkoxy group. Examples include compounds substituted with a methyl group. Specific examples include hexamethoxymethyl melamine, hexaethoxymethyl melamine, hexapropoxymethyl melamine, hexabutoxybutyl melamine, and the like. Among them, hexamethoxymethyl melamine represented by the following structural formula (C-1) is used. preferable.

  Urea-based crosslinking agents include compounds in which urea and formaldehyde are reacted to replace amino group hydrogen atoms with hydroxymethyl groups; urea, formaldehyde and lower alcohols are reacted to convert amino group hydrogen atoms into lower alkoxy groups. Examples include compounds substituted with a methyl group. Specific examples include bismethoxymethylurea, bisethoxymethylurea, bispropoxymethylurea, bisbutoxymethylurea, and the like, with bismethoxymethylurea being preferred.

［式中、Ｒ_３とＲ_４はそれぞれ独立して水酸基又は低級アルコキシ基であり、Ｒ_５とＲ_６はそれぞれ独立に水素原子、水酸基又は低級アルコキシ基であり、ｐは０〜２の整数である。］ As an alkylene urea type crosslinking agent, the compound represented by the following general formula (C-2) is mentioned.

[Wherein, R ₃ and R ₄ are each independently a hydroxyl group or a lower alkoxy group, R ₅ and R ₆ are each independently a hydrogen atom, a hydroxyl group or a lower alkoxy group, and p is an integer of 0 to 2. is there. ]

The lower alkoxy group for R ₃ and R ₄ is preferably an alkoxy group having 1 to 4 carbon atoms. This alkoxy group may be linear or branched. R ₃ and R ₄ may be the same or different from each other, but are preferably the same.

The lower alkoxy group for R ₅ and R ₆ is preferably an alkoxy group having 1 to 4 carbon atoms. This alkoxy group may be linear or branched. R ₅ and R ₆ may be the same or different from each other, but are preferably the same. P is an integer of 0 to 2, preferably 0 or 1.

  The alkylene urea crosslinking agent is particularly preferably at least one of a compound in which p is 0 (ethylene urea crosslinking agent) or a compound in which p is 1 (propylene urea crosslinking agent).

  The compound represented by the general formula (C-2) is obtained by reacting a product obtained by condensation reaction of alkylene urea and formalin with a lower alcohol.

  Examples of the alkylene urea crosslinking agent include mono and / or dihydroxymethylated ethylene urea, mono and / or dimethoxymethylated ethylene urea, mono and / or diethoxymethylated ethylene urea, mono and / or dipropoxymethylated ethylene urea, Ethylene urea-based crosslinkers such as mono and / or dibutoxymethylated ethylene urea; mono and / or dihydroxymethylated propylene urea, mono and / or dimethoxymethylated propylene urea, mono and / or diethoxymethylated propylene urea, mono And / or propylene urea-based crosslinking agents such as dipropoxymethylated propylene urea, mono and / or dibutoxymethylated propylene urea; 1,3-di (methoxymethyl) 4,5-dihydroxy-2-imidazolidinone, 1 , 3-Di (methoxymethyl) -4, - dimethoxy-2-imidazolidinone.

The epoxy-based crosslinking agent is not particularly limited as long as it has an epoxy group, and can be arbitrarily selected and used. Among these, it is preferable to have two or more epoxy groups. By having two or more epoxy groups, the crosslinking reactivity with the resin component (A) is improved. The number of epoxy groups is preferably 2 or more, more preferably 2 to 4, and most preferably 2. The following are suitable as the epoxy-based crosslinking agent.

The oxetane-based crosslinking agent is not particularly limited as long as it is a compound having an oxetane skeleton, but is preferably a compound represented by the following chemical formula.

  Examples of the glycoluril-based crosslinking agent include glycoluril derivatives in which the N position is substituted with one or both of a hydroxyalkyl group and an alkoxyalkyl group having 1 to 4 carbon atoms. Such a glycoluril derivative is obtained by reacting a product obtained by condensation reaction of glycoluril and formalin with a lower alcohol.

  Glycoluril-based crosslinkers include mono, di, tri and / or tetrahydroxymethylated glycoluril, mono, di, tri and / or tetramethoxymethylated glycoluril, mono, di, tri and / or tetraethoxymethylated Examples include glycoluril, mono, di, tri and / or tetrapropoxymethylated glycoluril, mono, di, tri and / or tetrabutoxymethylated glycoluril. Said crosslinking agent may be used independently and may be used in combination of 2 or more type.

  (C) 0.5-30 mass parts is preferable with respect to 100 mass parts of (A) component, as for content of a component, 0.5-25 mass parts is more preferable, and 0.5-20 mass parts is the most. preferable. When the content exceeds 0.5 parts by mass, the crosslinking formation proceeds sufficiently and a good insulating film can be formed. When the content is less than 30 parts by mass, the storage stability of the composition for forming an insulating film can be kept good, and deterioration of the formed insulating film over time is suppressed.

<(D) component>
The composition for forming an insulating film according to the present invention further contains a component (D) that is an organic solvent. The component (D) is not particularly limited as long as it can dissolve a resin and a crosslinking agent such as alcohols and esters. For example, lactones such as γ-butyrolactone;
Ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl-n-amyl ketone, methyl isoamyl ketone, 2-heptanone;
Polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol;
Compounds having an ester bond such as ethylene glycol monoacetate, diethylene glycol monoacetate, propylene glycol monoacetate, dipropylene glycol monoacetate, monomethyl ether, monoethyl ether, monopropyl of the polyhydric alcohols or the compound having an ester bond Derivatives of polyhydric alcohols such as ethers, monoalkyl ethers such as monobutyl ether or compounds having an ether bond such as monophenyl ether [in these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME) Is preferred];
Cyclic ethers such as dioxane and esters such as methyl lactate, ethyl lactate (EL), methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, ethyl pyruvate, methyl methoxypropionate, ethyl ethoxypropionate;
Aromatic organic solvents such as anisole, ethyl benzyl ether, cresyl methyl ether, diphenyl ether, dibenzyl ether, phenetol, butyl phenyl ether, ethylbenzene, diethylbenzene, amylbenzene, isopropylbenzene, toluene, xylene, cymene, mesitylene, etc. be able to.

These organic solvents may be used independently and may be used as 2 or more types of mixed solvents.
Among these, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), and EL are preferable.

Moreover, the mixed solvent which mixed PGMEA and the polar solvent is preferable. The blending ratio (mass ratio) may be appropriately determined in consideration of the compatibility between PGMEA and the polar solvent, preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. It is preferable to be within the range.
More specifically, when EL is blended as a polar solvent, the mass ratio of PGMEA: EL is preferably 1: 9 to 9: 1, more preferably 2: 8 to 8: 2. Moreover, when mix | blending PGME as a polar solvent, the mass ratio of PGMEA: PGME becomes like this. Preferably it is 1: 9-9: 1, More preferably, it is 2: 8-8: 2, More preferably, it is 3: 7-7: 3.

In addition, as the component (D), a mixed solvent of at least one selected from PGMEA and EL and γ-butyrolactone is also preferable. In this case, the mixing ratio of the former and the latter is preferably 70:30 to 95: 5.
The amount of component (D) used is not particularly limited, but is a concentration that can be applied to a substrate or the like, and is appropriately set according to the coating film thickness. Generally, the solid content of the composition for forming an insulating film The concentration is 2 to 20% by mass, preferably 5 to 15% by mass.

  As a manufacturing method of the composition for insulating film formation concerning this invention, various components are melt | dissolved or disperse | distributed in (C) component which is a solvent, and it is obtained by mixing with a stirrer.

[Organic semiconductor devices]
An organic semiconductor element is manufactured by three aspects. Hereinafter, each aspect will be specifically described.

<First aspect>
Hereinafter, a 1st aspect is demonstrated in order using FIG. In FIG. 1 to FIG. 3, the same reference numerals indicate the names of the same parts, and the description of the duplicate reference numerals is omitted.

  In a first aspect, a process for forming an insulating film by applying the composition for forming an insulating film according to the present invention onto a substrate provided with a gate electrode layer (hereinafter referred to as an insulating film forming process), and the insulation A step of forming an organic semiconductor film on the film (hereinafter referred to as an organic semiconductor film formation step), and a step of forming a source electrode and a drain electrode on the organic semiconductor film (hereinafter referred to as an electrode formation step). Including. The organic semiconductor element 1 manufactured by this process is a so-called top contact type.

  The insulating film forming step may further include a step of forming the gate electrode layer 21 on the substrate 10. The substrate 10 can be made of resin, glass, silicon or the like. The material of the gate electrode layer 21 is not particularly limited as long as it can be formed on the substrate 10 at a low temperature. For example, organic materials such as polyaniline and polythiophene, and raw materials such as conductive ink are used. These are formed as electrode layers by coating on the substrate 10.

  The gate electrode layer 21 is made of metal such as gold, platinum, chromium, palladium, aluminum, indium, molybdenum, nickel, alloys using these metals, polysilicon, amorphous silicon, indium / tin oxide (ITO It is also possible to use inorganic materials such as tin oxide. These inorganic materials can be formed as electrodes by known photolithography. In addition, you may use said material individually or in combination of 2 or more types. A substrate on which a gate electrode is stacked from the beginning can also be used.

  The insulating film 30 is formed by applying the insulating film forming composition according to the present invention to the substrate 10 on which the gate electrode layer 21 is formed. The coating method of the composition for forming an insulating film is not particularly limited, and is a known spin coating method, dip coating method, printing method, roll coating method, cast method, spray coating method, doctor blade method, die coating. It is carried out by a wet process such as an ink jet method. Among these, it is preferable to use a spin coating method, a dip coating method, a printing method, a roll coating method, or the like in that the coating amount can be controlled to form a film with a desired film thickness.

  The insulating film forming composition applied on the substrate 10 is preferably dried at a predetermined temperature. The drying temperature is preferably 70 ° C. or higher and 200 ° C. or lower, and more preferably 180 ° C. or lower. When the heating temperature is within the above range, a dense insulating film can be formed, and electrical characteristics are improved. The drying time is preferably 5 to 120 minutes, and more preferably 5 to 100 minutes.

  The thickness of the insulating film 30 formed through such a process is 10 to 1000 nm, preferably 10 to 900 nm, and more preferably 10 to 800 nm.

  In the organic semiconductor film forming step, the organic semiconductor film 40 is formed on the insulating film formed in the insulating film forming step. As the organic semiconductor film 40, it is preferable to use a π-electron conjugated aromatic compound, a chain compound, an organic pigment, an organic silicon compound, or the like. Specific examples include pentacene derivatives, tetracene, anthracene, thiophene oligomer derivatives, phenylene derivatives, phthalocyanine compounds, polyacetylene derivatives, polythiophene derivatives, and cyanine dyes, but are not limited thereto.

  As a method for forming the organic semiconductor film 40, a known thin film forming method such as vapor deposition, coating, or adhesion from a solution can be used. However, when the substrate 10 is a resin, the method can be performed at a lower temperature. It is preferred to select a possible method.

  The thickness of the organic semiconductor film 40 is preferably 5 nm to 200 nm, and more preferably 20 nm to 100 nm. When the thickness is 200 nm or more, in the case of the top contact structure, the resistance in the film thickness direction portion increases, and the transistor characteristics deteriorate. If the thickness is 5 nm or less, a thin film is not formed and an island-shaped film is formed.

  In the electrode forming step, the drain electrode 22 and the source electrode 23 are formed on the organic semiconductor film 40 formed in the organic semiconductor film forming step. These are formed by the same method as the gate electrode layer 21. Further, the same material as that of the gate electrode layer 21 may be used, but it may be different.

<Second aspect>
In the second aspect, after forming a source electrode and a drain electrode on a substrate, an organic semiconductor film is formed, and the insulating film is formed by applying the insulating film forming composition according to the present invention on the organic semiconductor film. And forming a gate electrode layer over the insulating film.

  As shown in FIG. 2, the organic semiconductor element 1 </ b> A in this embodiment includes a drain electrode 22 and a source electrode 23 formed on a substrate 10, an organic semiconductor film 40 and an insulating film 30 formed thereon, and further thereon. This is a so-called bottom contact structure in which a gate electrode layer 21 is formed. In addition, the formation method of each structural member is performed by the method similar to a 1st aspect.

[Third embodiment]
According to a third aspect, a step of forming an organic semiconductor film on a substrate, and after forming a source electrode and a drain electrode on the organic semiconductor film, the composition for forming an insulating film according to the present invention is applied to form an insulating film And a step of forming a gate electrode layer on the insulating film.

  In this embodiment, as shown in FIG. 3, the organic semiconductor element 1 </ b> B includes an organic semiconductor film 40 formed on the substrate 10, a drain electrode 22 and a source electrode 23 formed thereon, and an insulating film 30, This is a so-called bottom contact structure in which the gate electrode layer 21 is formed. In addition, the formation method of each structural member is performed by the method similar to a 1st aspect.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the scope of the examples.

[Example 1]
A p-type organic thin film transistor having a top contact structure as shown in FIG. 1 was manufactured as an organic semiconductor element by the method described below. This was designated as Sample 1.

In the composition for forming an insulating film, 100 parts by mass of a resin represented by the following structural formula (A-1-a) (p-hydroxybenzylsilsesquioxane / phenylsilsesquioxane = 70/30 (molar ratio) ), Mw = 7000, Mw / Mn = 1.8) was prepared in propylene glycol monomethyl ether acetate (hereinafter referred to as PGMEA) so as to be 15% by mass.

  As the organic semiconductor film forming material, α, ω-dihexyl-sexithiophene (a, ω-dihexylxithiophene: trade name DH-6T: manufactured by Starck Vitec) was used. A commercially available polished indium / tin oxide glass substrate (ITO glass substrate) was used as the substrate. The gate electrode layer was formed by patterning the glass substrate by etching.

  First, the above-mentioned composition for forming an insulating film is applied onto a gate electrode layer formed on a glass substrate by a spin coating method, formed into a film, and then heated in air at 200 ° C. for 20 minutes for insulation. A film was formed. The thickness of the insulating film at this time was 360 nm.

  Next, the organic semiconductor film composition was formed to a thickness of 30 nm at a deposition rate of 1 mm / min by an organic molecular beam deposition method to form an organic semiconductor film. Next, gold electrodes were formed by vapor deposition as source / drain electrodes, and the p-type organic thin film transistor having the top contact structure shown in FIG. 1 was manufactured. The channel length at this time was 100 μm, the channel width was 2 mm, and the film thickness was 30 nm.

The voltage-current characteristics were measured at room temperature, in vacuum, and in a dark state. Further, the mobility of transistor characteristics was calculated using the following calculation formula. The results are shown in Table 1.
I _d = 1/2 × (L / W) × C _i × μ × (V _g −V _th ) ²
I _d : drain current (A)
L: Gate length (cm)
W: Gate width (cm)
C _i : Capacitance per unit volume (C / cm ² )
m: mobility (cm ² / Vs)
V _g : gate voltage (V)
V _th : gate voltage threshold (V)
In Example 1, the mobility was 0.10 cm ² / Vs, and V _th was 6.6 V.

[Example 2]
Instead of the resin represented by the above structural formula (A-1-a), a resin represented by the following structural formula (A-4-a) (p-methoxybenzylsilsesquioxy) was used as the insulating film forming composition. Example except that 100 parts by mass of sun / p-hydroxybenzylsilsesquioxane / phenylsilsesquioxane = 10/60/30 (molar ratio), Mw = 7000, Mw / Mn = 1.8) was used. A p-type organic thin film transistor was produced in the same manner as in Example 1. This was designated as Sample 2. Note that the film thickness of the insulating film at this time was 310 nm. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

Example 3
A p-type organic thin film transistor was produced in the same manner as in Example 1 except that a crosslinking agent represented by the following structural formula (C-1) was used as the insulating film forming composition. This was designated as Sample 3. The addition amount of this crosslinking agent was 10 mass parts with respect to 100 mass parts of resin. Note that the thickness of the insulating film at this time was 290 nm. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

Example 4
A p-type organic thin film transistor was produced in the same manner as in Example 3 except that a thermal acid generator represented by the following structural formula (B-2) was used as the composition for forming an insulating film. This was designated as Sample 4. Note that the film thickness of the insulating film at this time was 310 nm. The addition amount of the crosslinking agent and the thermal acid generator at this time was 10 parts by mass of the crosslinking agent and 2 parts by mass of the thermal acid generator with respect to 100 parts by mass of the resin, respectively.

Example 5
The composition described in Example 1 was used as the composition for forming an insulating film. [6,6] -Phenyl C61-butyric acid methyl ester (PCBM) (manufactured by Frontier Carbon Co.) represented by the following structural formula (E-1) was used as the organic semiconductor film forming material.

  As in Example 1, α, ω-dihexyl-sexithiophene was used as the organic semiconductor film forming material, and a commercially available indium / tin oxide glass substrate (ITO glass substrate) was used as the substrate. The gate electrode layer was formed by patterning the glass substrate by etching.

  First, the above-mentioned composition for forming an insulating film is applied onto a gate electrode layer formed on a glass substrate by a spin coating method, formed into a film, and then heated in air at 200 ° C. for 20 minutes for insulation. A film was formed. The thickness of the insulating film at this time was 360 nm.

  Next, the organic semiconductor film forming material was formed into a thickness of 30 nm by a spin coating method to form an organic semiconductor film. Next, gold electrodes were formed by vapor deposition as source / drain electrodes, and the n-type organic thin film transistor having the top contact structure shown in FIG. 1 was manufactured. The channel length at this time was 100 μm, the channel width was 2 mm, and the film thickness was 30 nm. This was designated as Sample 5. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

Example 6
As a test for organic solvent resistance, a mixed solvent of ethyl lactate (EL) and PGMEA (EL: PGMEA = 40: 60) was dropped on the substrate with an insulating film, immersed for 20 seconds, and the solvent was dried. Observed. The film thickness after immersion was measured by using Nanospec model 210XP manufactured by Nanometrics Japan. No change in film thickness was observed.

As a composition for forming an insulating film, the resin described in Example 1 is added with a crosslinking agent (C-3) represented by the following structural formula and a thermal acid generator represented by the following structural formula (B-1). Using. The addition amount of the crosslinking agent and the thermal acid generator was 10 parts by mass for the crosslinking agent and 3 parts by mass for the thermal acid generator with respect to 100 parts by mass of the resin, respectively. This composition for forming an insulating film was applied on a silicon substrate by a spin coating method and formed into a thickness of 30 nm to form an organic semiconductor film.

Example 7
As a composition for forming an insulating film, a resin (p-hydroxybenzylsilsesquioxy) represented by the following structural formula (A-7-a) is used instead of the resin represented by the structural formula (A-1-a). Sun / p- (1-ethoxyethoxy) benzylsilsesquioxane / phenylsilsesquioxane = 50/30/20 (molar ratio), Mw = 7500, Mw / Mn = 1.7) 100 parts by mass were used. A p-type organic thin film transistor was produced in the same manner as in Example 1 except for the above. This was designated as Sample 7. Note that the thickness of the insulating film at this time was 410 nm. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

Example 8
A p-type organic thin film transistor was produced in the same manner as in Example 7 except that a crosslinking agent represented by the following structural formula (C-4) was used as the composition for forming an insulating film. This was designated as Sample 8. The addition amount of this crosslinking agent was 10 mass parts with respect to 100 mass parts of resin. Note that the thickness of the insulating film at this time was 380 nm. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 1]
As a composition for forming an insulating film, instead of the resin described in Example 1, a poly (p-hydroxystyrene) resin represented by the following structural formula (A-8) (Mw = 8000, Mw / Mn = 1. 2) A p-type organic thin film transistor was manufactured by the same method as in Example 1 except that 100 parts by mass and an insulating film having a thickness of 390 nm were formed. This was designated as Comparative Sample 1. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 2]
In addition to 100 parts by mass of the resin represented by the structural formula (A-8) described in Comparative Example 1 as the composition for forming an insulating film, the crosslinking agent represented by the structural formula (C-1) described in Example 3 Was added in an amount of 10 parts by mass with respect to 100 parts by mass of the resin to form a 410 nm-thick insulating film, and a p-type organic thin film transistor was manufactured in the same manner as in Comparative Example 1. This was designated as Comparative Sample 2. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

[Comparative Example 3]
An n-type organic thin film transistor was manufactured using the composition for forming an insulating film described in Comparative Example 1 as the composition for forming an insulating film. This was designated as Comparative Sample 3. Further, the mobility of transistor characteristics was calculated in the same manner as in Example 1. The results are shown in Table 1.

  From this, it was shown that the composition for forming an insulating film according to the present invention can provide an organic semiconductor element that can be driven at a low voltage and has a stable driving voltage value.

It is the figure which showed the 1st aspect of the organic-semiconductor element based on this invention. It is the figure which showed the 2nd aspect of the organic-semiconductor element based on this invention. It is the figure which showed the 3rd aspect of the organic-semiconductor element based on this invention.

Explanation of symbols

1, 1A, 1B Organic semiconductor element 10 Substrate 21 Gate electrode layer 22 Drain electrode 23 Source electrode 30 Insulating film 40 Organic semiconductor film

Claims (13)

An insulating film forming composition for forming an insulating film between a gate electrode layer and an organic semiconductor film layer of an organic semiconductor element, comprising a resin component (A) having a silsesquioxane skeleton,
The said resin component (A) is a composition for insulating film formation containing the silsesquioxane resin (A1) which has the structural unit (a1) represented by the following general formula (a-1).

[Wherein, X represents an alkylene group having 1 to 15 carbon atoms or a divalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R ¹ represents a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or 2 carbon atoms. Represents an alkoxyalkyl group having ˜15, R ² represents an alkyl group having 1 to 4 carbon atoms, and n is 0 or 1. ] The composition for forming an insulating film according to claim 1, wherein the resin component (A) further contains a structural unit (a2) represented by the following general formula (a-2).

[Wherein R ³ represents an alkyl group having 1 to 15 carbon atoms or an aromatic hydrocarbon group having 6 to 15 carbon atoms. ]   The said structural unit (a1) is a composition for insulating film formation of Claim 1 or 2 contained 10-95 mol% with respect to all the structural units which comprise the said silsesquioxane resin (A1).   The said structural unit (a2) is a composition for insulating film formation of Claim 2 or 3 contained 5-50 mol% with respect to all the structural units which comprise the said silsesquioxane resin (A1).   The composition for forming an insulating film according to any one of claims 1 to 4, wherein the silsesquioxane resin (A1) has a mass average molecular weight of 1,000 or more and 10,000 or less.   The composition for insulating film formation as described in any one of Claims 1-5 containing the compound (B) which generate | occur | produces an acid or a base by the effect | action of light or a heat | fever.   The composition for insulating film formation as described in any one of Claims 1-6 containing a crosslinking agent component (C). Applying the composition for forming an insulating film according to claim 1 on a substrate provided with a gate electrode layer to form an insulating film;
Forming an organic semiconductor film on the insulating film;
Forming a source electrode and a drain electrode on the organic semiconductor film. Forming an organic semiconductor film after forming a source electrode and a drain electrode on a substrate;
Applying the composition for forming an insulating film according to any one of claims 1 to 7 on the organic semiconductor film to form an insulating film;
Forming a gate electrode layer on the insulating film. Forming an organic semiconductor film on the substrate;
After forming a source electrode and a drain electrode on the organic semiconductor film, a step of applying an insulating film forming composition according to any one of claims 1 to 7 to form an insulating film;
Forming a gate electrode layer on the insulating film.   The method for producing an organic semiconductor element according to any one of claims 8 to 10, wherein the composition for forming an insulating film is applied by spin coating, dip coating, printing, or roll coating.   Furthermore, the process of forming the said insulating film is a manufacturing method of the organic-semiconductor element as described in any one of Claims 8-10 which has the process of performing heat processing for 5 minutes-120 minutes at 70 to 200 degreeC.   The method of manufacturing an organic semiconductor element according to claim 8, wherein the insulating film has a thickness of 10 to 1000 nm.

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