Method for forming pattern of colored resist and composition used therefor

Abstract

The present invention provides, in order to form a good colored resist pattern: a composition for forming a resist underlayer film for the formation of a resist underlayer film that is disposed between a substrate and a colored resist film; a resist underlayer film which is formed using the composition for forming a resist underlayer film; and a laminated body using the resist underlayer film, a method for forming a pattern of a colored resist, and provides a self-luminous display element and a liquid crystal element.　The present invention specifically provides a composition for forming a resist underlayer film for the formation of a resist underlayer film that is disposed between a substrate and a colored resist film, the composition for forming a resist underlayer film containing an alkali-soluble resin and a solvent. The resist underlayer film, which is formed by baking the composition for forming a resist underlayer film, exhibits solvent resistance to a solvent that is contained in a resist material for forming the colored resist film, and exhibits solubility in an alkali developer solution for the colored resist film.

Description

Method for forming a colored resist pattern and composition used therein

[0001] The present invention relates to a method for forming a colored resist pattern and a composition used therein. More specifically, the present invention relates to a method for forming a colored resist pattern, a composition for forming a resist underlayer film, a resist underlayer film, a laminate, a self-luminous display element, and a liquid crystal display element.

[0002] Conventionally, anti-reflection circular polarizers have been used in self-luminous display elements such as organic light-emitting diodes (OLEDs) and micro LEDs. However, the use of polarizers reduces brightness due to light absorption by the polarizers. In recent years, there has been a trend toward not using anti-reflection circular polarizers. Instead of using anti-reflection circular polarizers, display devices have been proposed that suppress reflection of external light and improve brightness by providing partition walls made of black material in an area surrounding the display area (see Patent Documents 1 and 2).

[0003] Japanese Patent Application Laid-Open No. 2005-317271

[0004] To form black pixel partitions as described in Patent Documents 1 and 2, a colored resist material containing a photosensitive resin mixed with a coloring material is used. The colored resist material is applied to a substrate, and then exposed and developed to pattern the colored resist. Therefore, there is a constant demand for a method capable of successfully patterning a colored resist formed on a substrate. The inventors have conducted extensive research and found that when attempting to form a patterned colored resist using a colored resist material containing a dispersed pigment, residues of colorant, such as pigments and particles insoluble in developer, are generated on the substrate between adjacent resist patterns. Furthermore, it has been found that colored resist films have reduced adhesion to the substrate compared to resist films containing no coloring agent, making the resist pattern more likely to peel off from the substrate. While changing the composition of the resist material could be considered to solve the above-mentioned problems of residue and pattern peeling, changing the composition would undesirably deteriorate the properties of the colored resist film itself.

[0006] Therefore, it has been desired to provide a method for forming a colored resist pattern, in which the composition of the colored resist material is not changed so as not to sacrifice the properties of the film itself as a colored resist film, and the colored resist is then coated on a substrate, exposed, and developed to pattern the colored resist, in which no developer-insoluble colorant residue is generated on the substrate between adjacent resist patterns, the resist pattern is not easily peeled off from the substrate, and a good colored resist pattern can be formed.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a resist underlayer film-forming composition for forming a resist underlayer film to be disposed between the substrate and the colored resist film in order to form a good colored resist pattern, a resist underlayer film formed from the resist underlayer film-forming composition, and a laminate, a colored resist pattern-forming method, a self-luminous display element, and a liquid crystal element using the resist underlayer film.

[0005] As a result of extensive research conducted by the present inventors to solve the above-mentioned problems, they discovered that the above-mentioned problems can be solved by providing a specific resist underlayer film between a substrate and a colored resist film, and thus completed the present invention, which has the following gist.

[0006] That is, the present invention encompasses the following aspects. [1] A composition for forming a resist underlayer film for forming a resist underlayer film disposed between a substrate and a colored resist film, the composition for forming a resist underlayer film comprising an alkali-soluble resin and a solvent, and the resist underlayer film formed by baking the composition for forming a resist underlayer film exhibits solvent resistance to a solvent contained in a resist material for forming the colored resist film and exhibits solubility in an alkaline developer for the colored resist film. [2] The composition for forming a resist underlayer film according to [1], wherein the alkali-soluble resin is a polyamic acid. [3] The composition for forming a resist underlayer film according to [1] or [2], which contains a crosslinking agent. [4] The composition for forming a resist underlayer film according to [3], wherein the crosslinking agent is an epoxy compound. [5] The composition for forming a resist underlayer film according to any one of [1] to [4], which contains a development rate adjuster. [6] The composition for forming a resist underlayer film according to [5], wherein the development rate adjuster is a compound containing a phenolic hydroxyl group or a carboxy group. [7] A resist underlayer film that is a cured film of the composition for forming a resist underlayer film according to any one of [1] to [6]. [8] The resist underlayer film according to [7], which is non-photosensitive. [9] A laminate comprising a substrate, the resist underlayer film according to [7] or [8], and a colored resist film.

[10] The laminate according to [9], wherein the solvent resistance developing temperature of the resist underlayer film with respect to a solvent contained in a resist material for forming the colored resist film is set to be lower than the developer insolubilization temperature of the resist underlayer film with respect to an alkaline developer.

[11] A method for forming a colored resist pattern, comprising: a step of applying the composition for forming a resist underlayer film according to any one of [1] to [6] onto a substrate and baking the composition to form a resist underlayer film; a step of forming a colored resist film on the resist underlayer film; and a step of exposing the colored resist film to light and developing a desired portion of the colored resist film and the resist underlayer film formed under the desired portion of the colored resist film, thereby obtaining a colored resist pattern.

[12] The method for forming a colored resist pattern according to

[11] , wherein the baking performed when forming the resist underlayer film is performed under temperature conditions between a temperature at which the resist underlayer film exhibits solvent resistance to a solvent contained in a resist material for forming the colored resist film and a temperature at which the resist underlayer film becomes insolubilized in an alkaline developer.

[13] The method for forming a colored resist pattern according to

[11] or

[12] , wherein the colored resist film is formed using a pigment-dispersed resist material.

[14] The method for forming a colored resist pattern according to

[11] or

[12] , wherein the colored resist film is formed using a metal oxide particle-dispersed resist material.

[15] The laminate according to [9] or

[10] , wherein the resist underlayer film and the colored resist film are patterned.

[16] A self-luminous display element or liquid crystal display element having the laminate according to

[15] .

[0007] According to the present invention, it is possible to provide a composition for forming a resist underlayer film for forming a resist underlayer film that is disposed between a substrate and a colored resist film in order to form a good colored resist pattern, a resist underlayer film formed from the composition for forming a resist underlayer film, a laminate using the resist underlayer film, a method for forming a colored resist pattern, a self-luminous display element, and a liquid crystal display element.

[0008] Fig. 1 is a graph showing the relationship between the baking temperature of a resist underlayer film and the degree of solvent resistance of the resist underlayer film as a result of the baking, and the relationship between the baking temperature of a resist underlayer film and the degree of insolubilization in a developer of the resist underlayer film as a result of the baking. Fig. 2 is a schematic diagram showing the relationship between the baking temperature and the solubility of the resist underlayer film in a developer.

[0009] (Resist Underlayer Film) The resist underlayer film according to the present invention is disposed between the substrate and the colored resist film. The resist underlayer film is formed from a composition for forming a resist underlayer film.

[0010] <Composition for forming a resist underlayer film> The composition for forming a resist underlayer film of the present invention contains an alkali-soluble resin and a solvent. The resist underlayer film formed by baking the composition for forming a resist underlayer film of the present invention exhibits solvent resistance to the solvent contained in the resist material for forming the colored resist film and exhibits solubility in an alkaline developer for the colored resist film. The composition for forming a resist underlayer film of the present invention may also contain a crosslinking agent, a development speed adjuster, etc. By using a specific resist underlayer film formed from the composition for forming a resist underlayer film of the present invention, when the colored resist film formed on the resist underlayer film is exposed and developed to pattern the colored resist, it is possible to prevent residues from being generated on the substrate between adjacent resist patterns, prevent the resist pattern from being easily peeled off from the substrate, and form a good colored resist pattern.

[0011] <<Alkali-Soluble Resin>> The alkali-soluble resin is not particularly limited and can be appropriately selected depending on the purpose, as long as the resist underlayer film formed by baking the composition for forming a resist underlayer film of the present invention containing an alkali-soluble resin exhibits solvent resistance to the solvent contained in the resist material for forming the colored resist film and exhibits solubility in an alkaline developer for the colored resist film. It is more preferable that the alkali-soluble resin is a polyamic acid.

[0012] <<<Polyamic Acid>>> The polyamic acid that is the alkali-soluble resin according to the present invention is preferably a polyamic acid having a repeating unit represented by the following formula (1).

[0013] (R １ is a tetravalent organic group constituting a tetracarboxylic acid or a derivative thereof, and R ２ is a divalent organic group constituting a diamine, and k is a natural number.

[0014] The method for obtaining this polyamic acid is not particularly limited, but it can generally be obtained by reacting and polymerizing a diamine with a tetracarboxylic acid or its derivatives such as a tetracarboxylic acid dianhydride or a dicarboxylic acid dihalide, etc. Also, a method that usually can be used is to react and polymerize a diamine with a tetracarboxylic acid dianhydride (hereinafter abbreviated as acid dianhydride) in a polar solvent such as N-methylpyrrolidone.

[0015] The diamines that can be used to obtain polyamic acid are not particularly limited, and may be used alone or in combination of two or more. Specific examples include p-phenylenediamine, m-phenylenediamine, 4,4-methylene-bis(2,6-ethylaniline), 4,4'-methylene-bis(2-isopropyl-6-methylaniline), 4,4'-methylene-bis(2,6-diisopropylaniline), 2,4,6-trimethyl-1,3-phenylenediamine, 2,3,5,6-tetramethyl-1,4-phenylenediamine, o-tolidine, m-tolidine, 3,3',5,5'- Tetramethylbenzidine, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]hexafluoropropane, 4,4'-diamino-3,3'-dimethyldicyclohexylmethane, 4,4'-diaminodiphenyl ether, 3,4-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,2-bis(4-aniline) Hexafluoropropane, 2,2-bis(3-anilino)hexafluoropropane, 2,2-bis(3-amino-4-toluyl)hexafluoropropane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,4-bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)pentane, 1,6-bis(4-aminophenoxy)hexane, 1,10-bis(4-aminophenoxy)deca Examples of suitable diamines include bis[4-(4-aminophenoxy)phenyl]sulfone, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 3,5-diaminobenzoic acid, 4-aminobenzoic acid-4-aminophenyl, and 4,4'-diaminobenzanilide. It is also preferable to use a siloxane-containing diamine to enhance adhesion to the substrate. Examples of suitable siloxane-containing diamines include the following diamines:

[0016] (wherein p represents an integer of 1 to 10)

[0017] The acid dianhydride that can be used to obtain the polyamic acid is not particularly limited, and one or more of these may be used simultaneously. Specific examples of the acid dianhydride include aromatic tetracarboxylic acid dianhydrides such as pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, and 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride. In addition, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, Examples of the tetracarboxylic acid dianhydride include hydrates, alicyclic tetracarboxylic acid dianhydrides such as 2,3,5-tricarboxy-2-cyclopentaneacetic acid dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride and 3,5,6-tricarboxy-2-norbornane acetic acid dianhydride, and aliphatic tetracarboxylic acid dianhydrides such as 1,2,3,4-butane tetracarboxylic acid dianhydride.

[0018] In terms of the solubility of the polyamic acid resin coating film in an alkaline developer, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-cyclopentanetetracarboxylic acid dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenetetracarboxylic acid dianhydride, Acid dianhydrides consisting of tetracarboxylic acids in which four carbonyl groups are not directly bonded to aromatic rings, such as lenthrin succinic dianhydride, 2,3,5-tricarboxy-2-cyclopentane acetic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic dianhydride, and 3,5,6-tricarboxy-2-norbornane acetic dianhydride, are preferred, and 1,2,3,4-cyclobutane tetracarboxylic dianhydride is more preferred.

[0019] In the polymerization of polyamic acid, the ratio of the total number of moles of diamine to the total number of moles of acid dianhydride is preferably 0.8 to 1.2. As with ordinary polycondensation reactions, the closer this molar ratio is to 1, the higher the degree of polymerization of the resulting polymer. If the degree of polymerization is too low, the film strength will be insufficient. On the other hand, if the degree of polymerization is too high, workability during film production may be impaired. Therefore, the degree of polymerization of the product in the present invention is preferably such that the reduced viscosity is 0.05 to 5.0 dl / g (in N-methylpyrrolidone at a temperature of 30°C, at a concentration of 0.5 g / dl). In particular, the reduced viscosity is preferably 0.2 to 2.0 dl / g. Examples of polar solvents that can be used when reacting a diamine and an acid dianhydride in a polar solvent include N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N-vinylpyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, m-cresol, γ-butyrolactone, propylene glycol monomethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monoethyl ether, and propylene glycol mono-n-propyl ether. These may be used alone or in combination. Furthermore, even if a solvent does not dissolve polyamic acid, it may be mixed with the above solvent as long as the polyamic acid produced by the polymerization reaction does not precipitate. The reaction temperature between the diamine and the acid dianhydride can be selected from the range of −20 to 150°C, preferably −5 to 100°C. The polyamic acid thus obtained can be used as it is, or can be recovered and used after isolation by precipitation in a poor solvent such as methanol, ethanol, or water.

[0020] The content of the alkali-soluble resin in the composition for forming a resist underlayer film is not particularly limited, but is preferably 10% by mass to 95% by mass, and more preferably 20% by mass to 90% by mass, based on the film-constituting components. The film-constituting components refer to components other than the solvent in the composition for forming a resist underlayer film.

[0021] <<Solvent>> The composition for forming a resist underlayer film of the present invention can be easily prepared by uniformly mixing the components, and is used in the form of a solution dissolved in a suitable solvent. Examples of such solvents that can be used include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone. These solvents can be used alone or in combination of two or more kinds. Furthermore, high boiling point solvents such as propylene glycol monobutyl ether and propylene glycol monobutyl ether acetate can be mixed and used.

[0022] The composition for forming a resist underlayer film is preferably used after being filtered using a filter having a pore size of about 0.2 μm.

[0023] The content of the solvent in the composition for forming a resist underlayer film is not particularly limited, but is preferably 50% by mass to 99.99% by mass, more preferably 75% by mass to 99.95% by mass, and particularly preferably 90% by mass to 99.9% by mass.

[0024] <<Material Properties of the Composition for Forming a Resist Underlayer Film>> The composition for forming a resist underlayer film of the present invention can change the developer dissolution rate of the resist underlayer film in an alkaline developer for a colored resist film by changing the temperature conditions of the baking performed when forming the resist underlayer film. The composition for forming a resist underlayer film of the present invention exhibits properties, for example, as shown in FIG. 1 , depending on the baking temperature. FIG. 1 is a graph showing the degree of solvent resistance and the degree of insolubilization in a developer of the resist underlayer film after baking at different baking temperatures. In FIG. 1 , the degree of resistance of the resist underlayer film to a solvent contained in the resist material for forming the colored resist film is indicated by symbol A. Furthermore, in FIG. 1 , the degree of insolubilization of the resist underlayer film in a developer is indicated by symbol B. For example, when the resist underlayer film-forming composition contains a polyamic acid, as indicated by a1 in the broken line of symbol A, the resist underlayer film obtained by baking the resist underlayer film-forming composition of the present invention at a temperature of a1 or higher exhibits increased resistance to the solvents contained in the resist material due to the onset of imidization and crosslinking reactions. Up to a2, the higher the baking temperature, the higher the solvent resistance. At a temperature of a2 or higher, the solvent resistance reaches an acceptable level. The resist underlayer film obtained by baking at a baking temperature of a2 or higher does not undergo mixing even when a colored resist material is applied onto the resist underlayer film. Here, the baking temperature of a2 is also referred to as the "solvent resistance development temperature" of the resist underlayer film against the solvents contained in the colored resist material. On the other hand, as indicated by b1 in the broken line of symbol B, in the resist underlayer film obtained by baking the composition for forming a resist underlayer film of the present invention at a temperature of b1 or higher, an imidization reaction or a crosslinking reaction begins, and as the imidization or crosslinking progresses, the proportion of carboxylic acid in the composition decreases, thereby increasing the degree of insolubilization of the resist underlayer film in an alkaline developer. Note that if the baking temperature is b2 or higher, the resist underlayer film becomes insoluble in the developer. Here, the baking temperature of b2 is also referred to as the "developer insolubilization temperature" of the resist underlayer film in an alkaline developer.

[0025] In the present invention, it is preferable to use a composition for forming a resist underlayer film whose "solvent resistance developing temperature" is set lower than the "developer insolubilization temperature." Furthermore, in the present invention, it is preferable that the baking performed when forming the resist underlayer film is performed under temperature conditions between the "solvent resistance developing temperature" and the "developer insolubilization temperature" (corresponding to the temperature range indicated by symbol T in FIG. 1 ). A preferred baking temperature is, for example, around 130°C to 220°C when the composition for forming a resist underlayer film contains a polyamic acid. The baking step will also be described below in the section on the method for producing a colored resist pattern.

[0026] As described above, the resist underlayer film-forming composition of the present invention may contain, in addition to the alkali-soluble resin and solvent, a crosslinking agent, a development speed modifier, and the like. The crosslinking agent and development speed modifier are described in detail below. For example, when the resist underlayer film-forming composition contains an alkali-soluble polyamic acid resin or an epoxy compound crosslinking agent, baking the resist underlayer film-forming composition causes a portion of the polyamic acid to be imidized, and another portion to react with the epoxy compound. By adjusting the content of the polyamic acid, the content of the epoxy compound, the content of the development speed modifier, and the like, which are subjected to the imidization reaction in the resist underlayer film-forming composition, it is possible to adjust the interval between the "solvent resistance exhibiting temperature" and the "developer insolubilization temperature" (corresponding to the temperature range indicated by symbol T in FIG. 1 ) and the slope of the developer dissolution rate of the resist underlayer film (corresponding to the slope from b1 to b2 in the broken line indicated by symbol B in FIG. 1 ). The wider the interval between the "solvent resistance exhibiting temperature" and the "developer insolubilizing temperature" (corresponding to the temperature range indicated by symbol T in FIG. 1 ), the easier the handling of the resist underlayer film when it is produced. Furthermore, the smaller the slope of the dissolution rate of the resist underlayer film in the developer (corresponding to the slope from b1 to b2 in the broken line indicated by symbol B in FIG. 1 ), the wider the temperature margin. Furthermore, in the present invention, the slope of the dissolution rate of the resist underlayer film in the developer (corresponding to the slope from b1 to b2 in the broken line indicated by symbol B in FIG. 1 ) can be adjusted by adding a development speed adjuster to the composition for forming the resist underlayer film.

[0027] <<Crosslinking Agent>> The composition for forming a resist underlayer film of the present invention may contain a crosslinking agent in addition to the alkali-soluble resin and solvent. Examples of the crosslinking agent include epoxy compounds. Such compounds are not particularly limited as long as they have an epoxy group. For example, examples of compounds having at least two epoxy groups include tris(2,3-epoxypropyl)isocyanurate, 1,4-butanediol diglycidyl ether, 1,2-epoxy-4-(epoxyethyl)cyclohexane, glycerol triglycidyl ether, diethylene glycol diglycidyl ether, 2,6-diglycidylphenyl glycidyl ether, 1,1,3-tris[p-(2,3-epoxypropoxy)phenyl]propane, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, 4,4'-methylenebis(N,N-diglycidylaniline), 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, trimethylolethane triglycidyl ether, bisphenol-A diglycidyl ether, and pentaerythritol polyglycidyl ether. Furthermore, polymers having epoxy groups can also be used as compounds having at least two epoxy groups. Such polymers can be used without particular limitation as long as they have epoxy groups. Such polymers can be produced by addition polymerization using an addition-polymerizable monomer having an epoxy group, or by reacting a polymer compound having a hydroxyl group with a compound having an epoxy group, such as epichlorohydrin or glycidyl tosylate. Examples of such polymers include addition-polymerized polymers such as polyglycidyl methacrylate, a copolymer of glycidyl methacrylate and ethyl methacrylate, a copolymer of glycidyl methacrylate, styrene, and 2-hydroxyethyl methacrylate, and poly(3,4-epoxycyclohexylmethyl methacrylate), as well as condensation-polymerized polymers such as epoxy novolac. The weight-average molecular weight of such polymers is, for example, 300 to 200,000.

[0028] Examples of compounds having at least two epoxy groups include epoxy resins having an amino group, such as Sumiepoxy ELM-434 and Sumiepoxy ELM-434L (manufactured by Sumitomo Chemical Co., Ltd.); epoxy resins having a cyclohexene oxide structure, such as Epolead GT-401, GT-403, GT-301, GT-302, Celloxide 2021, and Celloxide 3000 (manufactured by Daicel Corporation); bisphenol A type epoxy resins, such as JER1001, JER1002, JER1003, JER1004, JER1007, JER1009, JER1010, and JER828 (all manufactured by Mitsubishi Chemical Corporation); and bisphenol F type epoxy resins, such as Epolead GT-401, GT-403, GT-301, GT-302, Celloxide 2021, and Celloxide 3000 (manufactured by Daicel Corporation). phenol novolac epoxy resins such as JER152 and 154 (all manufactured by Mitsubishi Chemical Corporation), EPPN201 and 202 (all manufactured by Nippon Kayaku Co., Ltd.), cresol novolac epoxy resins such as EOCN-102, EOCN-103S, EOCN-104S, EOCN-1020, EOCN-1025 and EOCN-1027 (all manufactured by Nippon Kayaku Co., Ltd.) and JER180S75 (manufactured by Mitsubishi Chemical Corporation), alicyclic epoxy resins such as Denacol EX-252 (manufactured by Nagase Chemtex Corporation), CY175, CY177 and CY179 (all manufactured by CIBA-GEIGY) AG), Araldite CY-182, CY-192, CY-184 (all manufactured by CIBA-GEIGY AG), Epiclon 200, 400 (all manufactured by DIC Corporation), JER871, JER872 (all manufactured by Mitsubishi Chemical Corporation), ED-5661, ED-5662 (all manufactured by Celanese Coatings Co., Ltd.), and the like, together with aliphatic polyglycidyl ethers such as Denacol EX-611, EX-612, EX-614, EX-622, EX-411, EX-512, EX-522, EX-421, EX-313, EX-314, and EX-321 (manufactured by Nagase Chemtex Corporation), and triazine epoxy compounds TEPIC-S, TEPIC-SS, TEPIC-HS, TEPIC-VL, and TEPIC-FL (manufactured by Nissan Chemical Industries, Ltd.).The content of the epoxy group-containing compound is, for example, 70 parts by mass or less, preferably 50 parts by mass or less, and more preferably 45 parts by mass or less, relative to 100 parts by mass of the alkali-soluble resin. If the content of the epoxy group-containing compound is more than 70 parts by mass, sufficient solubility in the photoresist developer may not be obtained.

[0029] The content of the crosslinking agent in the composition for forming a resist underlayer film is not particularly limited, but is, for example, 70% by mass or less, and preferably 50% by mass or less, based on the alkali-soluble resin.

[0030] <<Development Speed ​​Adjuster>> The composition for forming a resist underlayer film of the present invention may contain a development speed adjuster in addition to the alkali-soluble resin and solvent. The development speed adjuster can be used for the purpose of adjusting the dissolution rate in a photoresist developer. Examples of the development speed adjuster include compounds containing a phenolic hydroxyl group or a carboxyl group.

[0031] For example, compounds having an aromatic ring substituted with a phenolic hydroxyl group or a carboxyl group are preferred. Examples include 1-naphthoic acid, 2-naphthoic acid, 1-naphthol, 2-naphthol, 1-aminonaphthalene, 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 3,7-dihydroxy-2-naphthoic acid, 6-bromo-2-hydroxynaphthalene, 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic ...2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid, 2-naphthalenedicarboxylic acid ,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-dihydroxynaphthalene, 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 6-hydroxy-1-naphthoic acid, 1-hydroxy-2-naphthoic acid, 3-hydroxy- 2-Naphthoic acid, 6-hydroxy-2-naphthoic acid, 1-bromo-2-hydroxy-3-naphthoic acid, 1-bromo-4-hydroxy-3-naphthoic acid, 1,6-dibromo-2-hydroxy-3-naphthoic acid, 3-hydroxy-7-methoxy-2-naphthoic acid, 1-amino-2-naphthol, 1,5-dimercaptonaphthalene, 1,4,5,8-naphthalenetetracarboxylic acid, 3,5-dihydroxy-2-naphthoic acid, 1,4-dihydroxy-2-naphthoic acid, 2-ethoxy-1-naphthoic acid, 2,6-dichloro-1 -naphthol, 2-hydroxy-3-naphthalenecarboxylic acid methyl ester, 6-hydroxy-2-naphthalenecarboxylic acid methyl ester, 3-hydroxy-7-methoxy-2-naphthalenecarboxylic acid methyl ester, 3,7-dihydroxy-2-naphthalenecarboxylic acid methyl ester, 2,4-dibromo-1-naphthol, 1-bromo-2-naphthol, 2-naphthalenethiol, 4-methoxy-1-naphthol, 6-acetoxy-2-naphthoic acid, 1,6-dibromo-1-naphthol, 2,6-dibromo-1,5-dihydroxynaphthalene, 1-acetyl-2-naphthol, 9-anthracenecarboxylic acid, 1,4,9,10-tetrahydroxyanthracene, and 1,8,9-trihydroxyanthracene, benzoic acid, 4-methylbenzoic acid, o-phthalic acid, m-phthalic acid, p-phthalic acid, 2-methoxybenzoic acid, isophthalic acid, terephthalic acid, 2-hydroxybenzoic acid, 3-hydroxybenzoic acid, 4-hydroxybenzoic acid Acid, 2-acetoxybenzoic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid, trimesic acid, 1,4-benzenedicarboxylic acid, 2,3-dimethoxybenzoic acid, 2,4-dimethoxybenzoic acid, 2,5-dimethoxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 4-acetylbenzoic acid, pyrrole Examples of the hydroxybenzoic acid include butyl hydroxybenzoic acid, ...

[0032] These compounds can also be used by reacting them with a polymer or a compound having one or more reactive groups. For example, in the case of a compound having a carboxy group or a phenolic hydroxyl group, compounds obtained by reacting with an epoxy compound such as tris(2,3-epoxypropyl)isocyanurate, 1,4-butanediol diglycidyl ether, 1,2-epoxy-4-(epoxyethyl)cyclohexane, glycerol triglycidyl ether, diethylene glycol diglycidyl ether, 2,6-diglycidylphenyl glycidyl ether, 1,1,3-tris(p-(2,3-epoxypropoxy)phenyl)propane, 1,2-cyclohexanedicarboxylic acid diglycidyl ester, 4,4'-methylenebis(N,N-diglycidylaniline), 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, trimethylolethane triglycidyl ether, bisphenol-A-diglycidyl ether, and pentaerythritol polyglycidyl ether, or a polymer containing a structure having an epoxy group such as glycidyl methacrylate, can be used. Examples of such development speed adjusters include compounds represented by the following formula (45): In formula (45), Ar is a benzene ring, a naphthalene ring, or an anthracene ring substituted with one or more hydroxyl groups and / or carboxy groups, and may be substituted with a group selected from the group consisting of an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a nitro group, a cyano group, a thiol group, a thioalkyl group having 1 to 5 carbon atoms, a phenoxy group, an acetyl group, an alkoxycarbonyl group having 1 to 5 carbon atoms, and a vinyl group.

[0033]

[0034] Examples of the development speed adjuster include a combination of the above-mentioned epoxy compounds such as tris(2,3-epoxypropyl)isocyanurate and 1,4-butanediol diglycidyl ether, and 1-hydroxy-2-naphthoic acid, 3-hydroxy-2-naphthoic acid, 3,7-dihydroxy-2-naphthoic acid, 1,2-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,3-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 6-hydroxy- Preferred are compounds obtainable by reacting 1-naphthoic acid, 3-hydroxy-2-naphthoic acid, 1-bromo-2-hydroxy-3-naphthoic acid, 1-bromo-4-hydroxy-3-naphthoic acid, 1,6-dibromo-2-hydroxy-3-naphthoic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 3,5-dihydroxy-2-naphthoic acid, and 1,4-dihydroxy-2-naphthoic acid with an aromatic compound having two or more carboxy groups or phenolic hydroxyl groups, such as terephthalic acid, isophthalic acid, p-hydroxybenzoic acid, m-hydroxybenzoic acid, o-hydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, and gallic acid.

[0035] The content of the development speed adjuster is, for example, 50 parts by mass or less, preferably 40 parts by mass or less, and more preferably 30 parts by mass or less, per 100 parts by mass of the alkali-soluble resin.

[0036] The resist underlayer film formed using the resist underlayer film-forming composition of the present invention is preferably a non-photosensitive film. For example, when a photosensitive film is used as the resist underlayer film, a certain amount of exposure is required to develop the photosensitive film. However, since the resist film of the present invention is a colored resist film, the resist material forming the colored resist film contains a colorant. When attempting to expose the colored resist film, the colorant interferes with the light transmission, resulting in poorer light transmittance toward the lower part of the colored resist film layer. Therefore, when a photosensitive resist underlayer film is used, the resist underlayer film is exposed to weak light that passes through the colored resist film. In such cases, the exposure dose may be insufficient, and the inherent function (e.g., developability) of the exposed photosensitive film may not be exhibited. Therefore, regardless of whether the resist underlayer film is photosensitive, it is preferable to control the solubility of the colored resist film in a developer by adjusting the baking temperature to form a colored resist pattern. Therefore, it is preferable to use a non-photosensitive resist underlayer film rather than a photosensitive one.

[0037] <Preparation of Resist Underlayer Film> The resist underlayer film of the present invention is a cured film of the composition for forming a resist underlayer film described above. The resist underlayer film can be produced, for example, by applying the composition for forming a resist underlayer film described above onto a substrate and baking it.

[0038] (Laminate) The laminate of the present invention comprises a substrate, the resist underlayer film of the present invention, and a colored resist film. The substrate and the colored resist film will be described in detail below.

[0039] In preparing the laminate, the resist underlayer film preferably has a solvent resistance developing temperature set lower than the developer insolubilization temperature. That is, for example, as shown in FIG. 1, the resist underlayer film preferably exhibits a solvent resistance developing temperature (see symbol a2 in FIG. 1) lower than the developer insolubilization temperature (see symbol b2 in FIG. 1). The baking conditions for forming the resist underlayer film will be described in detail below. The laminate of the present invention may be subjected to the method for forming a colored resist pattern described below to prepare a laminate in which a resist underlayer film and a colored resist film are patterned. The self-luminous display element or liquid crystal display element of the present invention can be provided by using a laminate having such a patterned colored resist pattern. The self-luminous display element or liquid crystal display element of the present invention will be described in detail below.

[0040] (Method for forming a colored resist pattern) The method for forming a colored resist pattern of the present invention comprises at least the following steps: a step of forming a resist underlayer film on a substrate using the composition for forming a resist underlayer film of the present invention, a step of forming a colored resist film on the resist underlayer film, and a step of exposing and developing the colored resist.

[0041] The composition for forming a resist underlayer film of the present invention is applied onto a substrate by an appropriate coating method such as a spinner or a slit coater, and then baked using a heating means such as a hot plate to form a resist underlayer film.

[0042] <Substrate> Examples of the substrate include glass substrates, quartz substrates, glass substrates coated with metals such as aluminum, molybdenum, and chromium, polysilicon, ITO, IZO, SiN, and SiO ２ Examples of the organic film include glass substrates on which an inorganic film such as a polyimide film, a polyethylene terephthalate film, a polycarbonate film, and a cycloolefin polymer film are formed, and semiconductor substrates such as silicon wafers, gallium arsenide, and gallium nitride. Examples of the organic film include, but are not limited to, films obtained from UV-curable resins such as color filters, overcoats, and planarizing films.

[0043] <Baking Step> The baking performed when forming the resist underlayer film is preferably performed under temperature conditions between the "solvent resistance developing temperature" (see symbol a2 in FIG. 1 ) of the resist underlayer film for the solvent contained in the resist material for forming the colored resist film and the "developer insolubilization temperature" (see symbol b2 in FIG. 1 ) of the resist underlayer film for the alkaline developer of the colored resist film. That is, the resist underlayer film is preferably formed by baking a coating film made of the composition for forming the resist underlayer film at a desired temperature within the temperature range indicated by symbol T in FIG. 1 . For example, if the baking temperature is set to b2 or higher, the resist underlayer film will not dissolve in the developer, so the temperature must be lower than b2. On the other hand, if the baking temperature is not set to a2 or higher, the resist underlayer film will dissolve in the solvent of the colored resist material, resulting in mixing with the resist material. Therefore, the baking temperature is preferably set to a temperature in the range of a2 or higher but lower than b2, and at a temperature that exhibits a desired development dissolution rate.

[0044] FIG. 2 is a schematic diagram showing the relationship between baking temperature and dissolution of a resist underlayer film in a developer. In FIG. 2(1), a resist underlayer film 2 is formed on a substrate 1. By baking a coating film of a resist underlayer film-forming composition, a resist underlayer film that is resistant to the solvent contained in the colored resist material is formed. In FIG. 2(2), a colored resist film 3 is formed on the resist underlayer film 2. In FIG. 2(2), irradiation from above a mask 4 is performed to develop the colored resist film 3 and the resist underlayer film 2 formed below the colored resist film 3. For example, when baked at a desirable baking temperature, the resist underlayer film dissolves at a favorable developer dissolution rate, and as shown in FIG. 2(4), only the portions of the resist underlayer film 2 corresponding to the portions without the colored resist film 3 are dissolved, forming a favorable resist pattern. On the other hand, if the resist underlayer film is baked at a temperature higher than the desired baking temperature, the resist underlayer film becomes less soluble in the developer. As a result, as shown in FIG. 2(3), the resist underlayer film 2 formed under the colored resist film 3 may not dissolve beyond the area corresponding to the absence of the colored resist film 3 (residual film, residue, etc.). In this case, a resist pattern with a good shape cannot be obtained. Furthermore, if the resist underlayer film is baked at a temperature lower than the desired baking temperature, the resist underlayer film 2 formed under the colored resist film 3 may dissolve beyond the area corresponding to the absence of the colored resist film 3, as shown in FIG. 2(5). In this case, a resist pattern with a good shape cannot be obtained. In this way, a coating film formed from the resist underlayer film-forming composition of the present invention can be baked under suitable temperature conditions that allow the resist underlayer film to dissolve in the developer at a desired rate, thereby forming a resist pattern with a good shape. The baking conditions are appropriately selected from, for example, a baking temperature of 120°C to 250°C and a baking time of 0.5 minutes to 120 minutes. Preferably, the baking temperature is 130° C. to 200° C. and the baking time is 1 minute to 60 minutes.

[0045] The film thickness of the resist underlayer film is, for example, 0.001 μm (1 nm) to 10 μm, 0.002 μm (2 nm) to 1 μm, 0.005 μm (5 nm) to 0.5 μm (500 nm), 0.001 μm (1 nm) to 0.05 μm (50 nm), 0.002 μm (2 nm) to 0.05 μm (50 nm), 0.003 μm (3 nm) to 0.05 μm (50 nm), 0.004 μm (4 nm) to 0.05 μm (50 nm), or 0.005 μm (5 nm) to 0.05 μm (50 nm).

[0046] A colored resist film is formed on the resist underlayer film. The colored resist film has a thickness of, for example, 50 μm or less, 30 μm or less, or 20 μm or less.

[0047] The colored resist film formed on the resist underlayer film by a known method (for example, coating and baking a colored resist material) is not particularly limited as long as it responds to light or electron beam (EB) used for irradiation. Either a negative photoresist or a positive photoresist can be used.

[0048] <Colored Resist Film> The colored resist film of the present invention is formed using a colored resist material. The colored resist material refers to a material in which a colorant is added to a commonly known resist material. The colorant is not particularly limited, and for example, organic or inorganic pigments can be used alone or in combination. A dye can also be added within a range that does not reduce heat resistance. Furthermore, metal oxide particles can be used as the inorganic pigment. In particular, white particles (titanium oxide, zirconium oxide, etc.) can be added. Other examples of inorganic pigments include black inorganic pigments (carbon black, zirconium nitride, zirconium oxide, titanium black, etc.). Furthermore, organic pigments can include black organic pigments (perylene black, lactam black, aniline black, anthraquinone black, azo-based black pigments, etc.). A preferred embodiment of the colored resist film of the present invention is a colored resist film formed using a pigment-dispersed resist material. A preferred embodiment of the colored resist film of the present invention is a colored resist film formed using a metal oxide particle-dispersed resist material.

[0049] Any colorant that can be normally contained in a resist material can be used without any particular restrictions. A preferred embodiment of the resist material will be described below. In this specification, resists that respond to electron beams (EB) are also referred to as photoresists. Examples of photoresists include positive photoresists composed of an acrylic-soluble resin such as a phenol novolac resin, a cresol novolac resin, an acrylic acid copolymer, a methacrylic acid copolymer, a hydroxystyrene copolymer, a hydroxyphenylacrylamide copolymer, a hydroxyphenylmethacrylamide copolymer, or a hydroxyphenylmaleimide copolymer, and a 1,2-naphthoquinone diazide sulfonic acid ester; chemically amplified positive photoresists composed of a binder having a group that is decomposed by acid to increase the alkaline dissolution rate and a photoacid generator; and photoresists that are decomposed by acid to increase the alkaline dissolution rate of the photoresist. Examples of such photoresists include chemically amplified positive photoresists that consist of a low molecular weight compound that increases the dissolution rate, an alkali-soluble binder, and a photoacid generator; chemically amplified positive photoresists that consist of a binder having a group that decomposes in acid to increase the alkali dissolution rate, a low molecular weight compound that decomposes in acid to increase the alkali dissolution rate of the photoresist, and a photoacid generator; resists containing metal elements; negative photoresists that consist of an alkali-soluble resin, a polyunsaturated group-containing monomer, and a photoradical initiator; and negative photoresists that consist of an alkali-soluble resin, a polyfunctional cationically polymerizable monomer, and a photocationic initiator.

[0050] For example, an alkaline developer is used for development. The development temperature is, for example, 5°C to 50°C. The development time is, for example, 10 seconds to 300 seconds. Examples of alkaline developers that can be used include aqueous solutions of alkalis such as inorganic alkalis (e.g., sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, and aqueous ammonia); primary amines (e.g., ethylamine and n-propylamine); secondary amines (e.g., diethylamine and di-n-butylamine); tertiary amines (e.g., triethylamine and methyldiethylamine); alcohol amines (e.g., dimethylethanolamine and triethanolamine); quaternary ammonium salts (e.g., tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline); and cyclic amines (e.g., pyrrole and piperidine). Furthermore, the aqueous solutions of the alkalis may be used by adding an appropriate amount of alcohols (e.g., isopropyl alcohol) or a nonionic surfactant. Among these, preferred developers are aqueous solutions of potassium hydroxide or quaternary ammonium salts, more preferably aqueous solutions of tetramethylammonium hydroxide and choline. Furthermore, surfactants and the like may also be added to these developers. For example, if the colored resist film is a positive resist film, the colored resist film in the exposed portion is dissolved by the developer upon exposure, while the colored resist film in the unexposed portion remains. In this case, during development, in addition to the colored resist film in the exposed portion, the resist underlayer film formed below the colored resist film in the exposed portion is also dissolved by the developer. That is, the resist underlayer film corresponding to the exposed portion from which the colored resist film has disappeared upon development is also removed by development. By removing the resist underlayer film, the residue of the colored resist film after development is also removed. In this way, the colored resist film in the desired portion and the resist underlayer film formed below the colored resist film in the desired portion are removed by development, so that no residue of the colored resist film is generated, and the patterned colored resist film is not peeled off, resulting in the formation of a good colored resist pattern. Alternatively, if the colored resist film is a negative resist film, the colored resist film in the unexposed portion is dissolved by the developer upon exposure, while the colored resist film in the exposed portion remains.In this case, during development, not only the colored resist film in the unexposed portions but also the resist underlayer film formed below the colored resist film in the unexposed portions is dissolved by the developer. That is, the resist underlayer film corresponding to the unexposed portions from which the colored resist film has been removed by development is also removed by development. By removing the resist underlayer film, the residue of the colored resist film after development is also removed. In this way, by removing the colored resist film in the desired portions and the resist underlayer film formed below the colored resist film in the desired portions by development, no residue of the colored resist film is left, and the patterned colored resist film is not peeled off, resulting in the formation of a good colored resist pattern.

[0051] (Self-luminous display element) The self-luminous display element of the present invention has a colored resist pattern formed by the above-mentioned method for forming a colored resist pattern according to the present invention. That is, the self-luminous display element of the present invention has a laminate in which the above-mentioned colored resist pattern formation is applied to the laminate of the present invention described in the above (Laminate) section, and a resist underlayer film and a colored resist film are patterned. Here, examples of the self-luminous display element include light-emitting diodes (OLEDs) and micro LEDs that use organic EL.

[0052] (Liquid Crystal Display Element) The liquid crystal display element of the present invention has a colored resist pattern formed by the above-mentioned method for forming a colored resist pattern according to the present invention. That is, the liquid crystal display element of the present invention has a laminate in which a resist underlayer film and a colored resist film are patterned by applying the above-mentioned colored resist pattern formation to the laminate of the present invention described in the above (Laminate) section. Examples of the liquid crystal display element include a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, an IPS (In-Plane Switching) mode, a VA (Vertical Alignment) mode, an OCB (Opticaly Compensated Birefringence) mode, an FFS (Fringe Field Switching) mode, and a PSA (Polymer Sustained Alignment) mode.

[0053] The present invention will now be described in detail with reference to examples, but the present invention is not limited to these examples. In the examples, the apparatus and conditions used for sample preparation and analysis of physical properties are as follows:

[0054] (1) Ultraviolet irradiation device Device: PLA-600FA manufactured by Canon Inc. (2) Developing device Device: AD-1200 manufactured by Takizawa Sangyo Co., Ltd. (3) Gel permeation chromatography (GPC) Device: Shimadzu Corporation Column: Shodex (registered trademark) GPC K-803L, GPC K-804L manufactured by Resonac Corporation Column temperature: 40°C Eluent: Tetrahydrofuran The number average molecular weight (hereinafter referred to as Mn) and the weight average molecular weight (hereinafter referred to as Mw) are expressed in polystyrene equivalent values. (4) Residue evaluation Device: Optical microscope MX61A manufactured by Olympus Corporation Device: Scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation

[0055] The abbreviations have the following meanings: PMDA: pyromellitic dianhydride 6FDA: 4,4'-(hexafluoroisopropylidene)diphthalic anhydride ODPA: 4,4'-oxydiphthalic anhydride PA: phthalic anhydride BAFP: 2,2-bis(3-amino-4-toluyl)hexafluoropropane DDS: 4,4'-diaminodiphenyl sulfone TFMB: 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl DBA: 3,5-diaminobenzoic acid PMA: pyromellitic acid QD: a compound synthesized by the condensation reaction of 1 mol of α,α,α'-tris(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene with 2 mol of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride GT-401: butanetetracarboxylic acid Tetra(3,4-epoxycyclohexylmethyl)-modified ε-caprolactone [Epolead GT-401, manufactured by Daicel Corporation] ELM-434: 4,4'-methylenebis(N,N-diglycidylaniline) [Sumiepoxy ELM-434, manufactured by Sumitomo Chemical Co., Ltd.] PGME: Propylene glycol monomethyl ether PGMEA: Propylene glycol monomethyl ether acetate TMAH: Tetramethylammonium hydroxide

[0056] Synthesis Example 1 Synthesis of Polyamic Acid (Polyamic Acid) 4.36 g of PMDA, 1.19 g of DBA, and 4.26 g of BAFP were reacted in 55.6 g of PGME at 60° C. for 25 hours to obtain a solution [A] containing polyamic acid (polyamic acid). GPC analysis of the obtained polyamic acid revealed that the weight average molecular weight Mw was 7,600 (standard polystyrene equivalent) and the number average molecular weight Mn was 4,100.

[0057] Synthesis Example 2 Synthesis of Polyamic Acid (Polyamic Acid) 7.55 g of 6FDA, 2.48 g of DDS, and 1.52 g of DBA were reacted in 65.5 g of PGME at 40° C. for 24 hours. After cooling the resulting solution to room temperature, 0.89 g of PA and 5.0 g of PGME were added, and the reaction was continued at room temperature for 12 hours to obtain a solution [B] containing polyamic acid (polyamic acid). GPC analysis of the resulting polyamic acid revealed a weight average molecular weight Mw of 7040 (standard polystyrene equivalent) and a number average molecular weight Mn of 4570.

[0058] (Synthesis Examples 3 to 8) <Synthesis of Polyamic Acid (Polyamic Acid)> Using the compounds listed in Table 1, solutions [C] to [H] containing polyamic acid (polyamic acid) were obtained in the same manner as in Synthesis Example 2. The compositions of each solution are listed in Table 1, and the molecular weights are listed in Table 2.

[0059]

[0060]

[0061] Synthesis Example 10 Synthesis of Developability Adjusting Compound 19.0 g of 3,7-dihydroxy-2-naphthoic acid, 10 g of tris(2,3-epoxypropyl)isocyanurate, and 0.552 g of benzyltriethylammonium chloride were reacted in 118 g of cyclohexanone at 130° C. for 24 hours to obtain a solution [a] containing a developability adjusting compound (a compound represented by the following formula (t)) which is a development speed adjusting agent.

[0062]

[0063] Example 1 Preparation of composition for forming resist underlayer film 4.38 g of solution [a] containing a developability adjusting compound, 0.630 g of 4,4′-methylenebis(N,N-diglycidylaniline), 52.3 g of PGME, and 67.5 g of PGMEA were added to 14.0 g of solution [A] containing polyamic acid (polyamic acid), and the mixture was stirred at room temperature for 30 minutes to prepare composition [1] for forming resist underlayer film.

[0064] Example 2 Preparation of composition for forming resist underlayer film To 2.05 g of solution [B] containing polyamic acid (polyamic acid), 0.06 g of PMA, 0.03 g of 4,4′-methylenebis(N,N-diglycidylaniline), 11.98 g of PGME, and 5.88 g of PGMEA were added, and the mixture was stirred at room temperature for 30 minutes to prepare composition [2] for forming resist underlayer film.

[0065] Examples 3 to 10 <Preparation of Composition for Forming Resist Underlayer Film> Compositions [3] to

[10] for forming resist underlayer film shown in Table 3 were prepared in the same manner as in Example 2.

[0066]

[0067] Reference Synthesis Example 1 Synthesis of Acrylic Polymer A1 8.20 g of N-(4-hydroxyphenyl)methacrylamide, 2.19 g of 2-hydroxyethyl methacrylate, 3.77 g of N-cyclohexylmaleimide, and 0.28 g of 2,2'-azobis(isobutyronitrile) were dissolved in 65.76 g of cyclopentanone, and the mixture was allowed to react at 90°C for 20 hours to obtain an acrylic polymer solution (solids concentration 18% by mass) (A1). The resulting acrylic polymer had an Mn of 5,100 and an Mw of 7,600.

[0068] Reference Synthesis Example 2 Synthesis of Acrylic Polymer A2 6.20 g of N-(4-hydroxyphenyl)methacrylamide, 2.28 g of 2-hydroxyethyl methacrylate, 6.27 g of N-cyclohexylmaleimide, and 0.29 g of 2,2'-azobis(isobutyronitrile) were dissolved in 68.49 g of cyclopentanone, and the mixture was allowed to react at 90°C for 20 hours to obtain an acrylic polymer solution (solids concentration 18% by mass) (A2). The resulting acrylic polymer had an Mn of 5,200 and an Mw of 10,000.

[0069] (Reference Synthesis Example 3) <Preparation of organic black pigment resist> 5.82 g of acrylic polymer solution (A1), 7.18 g of acrylic polymer solution (A2), 0.73 g of QD, 0.72 g of GT-401, 4.75 g of PGMEA, 1.39 g of cyclopentanone, were dissolved and stirred at room temperature for 30 minutes. To the resulting solution, 3.15 g of a solution (solid content concentration 21% by mass) obtained by dispersing lactam black Irgaphor Black S0100CF (manufactured by BASF) in PGMEA was added, and the mixture was stirred at room temperature for 30 minutes to prepare organic black pigment resist [X] (solid content concentration 18% by mass).

[0070] (Evaluation 1) <Evaluation when a resist underlayer film made from a resist underlayer film-forming composition is provided> The resist underlayer film-forming composition [1] was applied to a glass substrate with an ITO film using a spinner, dried on a hot plate at 100°C for 120 seconds, and then baked on a hot plate at temperatures of 170°C, 175°C, and 180°C for 60 seconds to form a resist underlayer film with a film thickness of 40 nm. The obtained resist underlayer film was insoluble in PGME, PGMEA, and cyclopentanone. A 1 μm-thick organic black pigment resist [X] film was formed on the obtained resist underlayer film, and a mixed ultraviolet light of g, h, and i was irradiated at 250 mJ / cm through a mask set to form a line / space pattern of 1.0 to 50 μm. ２ The resist underlayer film was irradiated with light. Thereafter, paddle development was performed for 60 seconds in a 2.38% TMAH aqueous solution at 23°C, followed by rinsing with running ultrapure water for 30 seconds. The coating film on which this line / space pattern was formed was observed using an optical microscope and a scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation. Regardless of the temperature at which the resist underlayer film was baked, the exposed areas of the resist underlayer film as well as the photoresist dissolved, the line / space pattern of 2.5 μm or more remained in close contact, and no residue or residual film was observed in the openings.

[0071] (Evaluation 2) <Evaluation when only a colored photoresist film is provided> An organic black pigment resist [X] film was formed to a thickness of 1 μm on a glass substrate with an ITO film, and a mixed ultraviolet light of g, h, and i was irradiated at 250 mJ / cm through a mask set to form a line / space pattern of 1.0 to 50 μm. ２ The resist was irradiated with light. Thereafter, paddle development was carried out for 60 seconds in a 2.38% TMAH aqueous solution at 23°C, followed by rinsing with running ultrapure water for 30 seconds. The coating film on which this line / space pattern had been formed was observed using an optical microscope and a scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation. The exposed areas of the photoresist film had dissolved, and line / space patterns of 30 μm or more remained adhered, but line / space patterns of 20 μm or less had all peeled off. A large amount of granular residue was confirmed in the openings.

[0072] (Evaluation 3) <Evaluation of the case where a resist underlayer film was formed from a resist underlayer film-forming composition at a low baking temperature> The resist underlayer film-forming composition [1] was applied to an ITO-coated glass substrate using a spinner, dried on a hot plate at 100°C for 120 seconds, and then baked on a hot plate at temperatures of 140°C and 150°C for 60 seconds to form a resist underlayer film with a thickness of 40 nm. The resulting resist underlayer film was dissolved in both PGME and cyclopentanone. The resulting resist underlayer film was subjected to paddle development in a 2.38% aqueous TMAH solution at 23°C for 60 seconds and then rinsed with running ultrapure water for 30 seconds, but the resist underlayer film still dissolved. When the resist underlayer film was baked at either temperature, solvent resistance was not obtained.

[0073] (Evaluation 4) <Evaluation of the case where a resist underlayer film was formed from a resist underlayer film-forming composition at a high baking temperature> The resist underlayer film-forming composition [1] was applied to an ITO-coated glass substrate using a spinner, dried on a hot plate at 100°C for 120 seconds, and then baked on a hot plate at temperatures of 230°C and 250°C for 60 seconds to form a resist underlayer film with a thickness of 40 nm. The resulting resist underlayer film was insoluble in PGME, PGMEA, and cyclopentanone. The resulting resist underlayer film was paddle-developed with a 2.38% aqueous TMAH solution at 23°C for 60 seconds, followed by rinsing with running ultrapure water for 30 seconds, but the resist underlayer film did not dissolve. Regardless of the baking temperature, the resist underlayer film exhibited solvent resistance but was unable to be developed.

[0074] (Evaluation 5-1) to (Evaluation 5-3) <Evaluation when a resist underlayer film made of a resist underlayer film-forming composition is provided> The resist underlayer film-forming composition [2] was applied to an alkali-free glass substrate using a spinner, dried on a hot plate at 100°C for 120 seconds, and then baked on a hot plate at temperatures of 165°C, 170°C, and 175°C for 60 seconds, to form a resist underlayer film with a film thickness of 50 nm. The obtained resist underlayer film was insoluble in PGMEA. On the obtained resist underlayer film, a general negative black pigment resist [Y] film using a composition containing PGMEA and a black pigment was formed to a thickness of 1 μm, and then irradiated with g, h, and i mixed ultraviolet light at 600 mJ / cm through a mask set to form a line / space pattern of 5.0 to 75 μm. ２The resist underlayer film was irradiated with light. Thereafter, the film was subjected to dipping development in a 0.04% KOH aqueous solution at 23°C for 60 seconds, followed by rinsing with running ultrapure water for 30 seconds. The coating film on which the line / space pattern was formed was observed using an optical microscope and a scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation. Regardless of the temperature at which the resist underlayer film was baked, the unexposed areas of the resist underlayer film dissolved along with the photoresist, the line / space pattern of 15 μm or more was adhered, and no residue or residual film was observed in the openings. The results of Evaluations 5-1 to 5-3 (Evaluations 5-1 to 5-3 are also collectively referred to as Evaluation 5) are shown in Table 4.

[0075] (Evaluation 6-1) to (Evaluation 11-1) <Evaluation in the case where a resist underlayer film made of a composition for forming a resist underlayer film was provided> Compositions [3] to [8] for forming a resist underlayer film listed in Table 3 were evaluated in the same manner as in Evaluation 5. The results of Evaluation 6-1 to Evaluation 11-1 are listed in Table 4.

[0076] (Evaluation 12-1) <Evaluation when only a colored photoresist film is provided> A typical negative black pigment resist [Y] film using a composition containing PGMEA and a black pigment was formed to a thickness of 1 μm on an alkali-free glass substrate, and a mixed ultraviolet light of g, h, and i was irradiated at 600 mJ / cm through a mask set to form a line / space pattern of 5.0 to 75 μm. ２ The sample was irradiated with light. Thereafter, the sample was subjected to dipping development in a 0.04% KOH aqueous solution at 23°C for 60 seconds, and then washed with running ultrapure water for 30 seconds. The coating film on which the line / space pattern was formed was observed using an optical microscope and a scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation. For all samples developed for any given time, the unexposed areas of the photoresist film were dissolved, and the line / space pattern of 15 μm or more was adhered, but a large amount of granular residue was confirmed in the openings. The results of Evaluation 12-1 are shown in Table 4.

[0077]

[0078] The evaluation criteria in Table 4 are as follows: [Pattern evaluation criteria] ◯: Line / space pattern of 15 μm or more present ×: Peeling of more than half present [Residue evaluation criteria] ◯: No residue ×: Residue present [Solvent resistance evaluation criteria] ◯: No film loss ×: Film dissolution

[0079] (Evaluation 13) <Evaluation when a resist underlayer film made of a resist underlayer film-forming composition is provided> The resist underlayer film-forming composition [2] was applied to an alkali-free glass substrate using a spinner, dried on a hot plate at 100°C for 120 seconds, and then baked on a hot plate at 175°C for 60 seconds to form a resist underlayer film with a film thickness of 50 nm. The resulting resist underlayer film was insoluble in PGMEA. A general negative black pigment resist [Z] film using a composition containing PGMEA and a black pigment was formed on the resulting resist underlayer film to a thickness of 1.6 μm, and ultraviolet light of a mixture of g, h, and i or i-line was applied at 20 mJ / cm through a mask set to form a line / space pattern of 5.0 to 20 μm. ２ The resist underlayer film was irradiated with light. Thereafter, the film was subjected to dipping development in a 0.04% KOH aqueous solution at 23°C for 30 seconds, and then washed with running ultrapure water for 30 seconds. The coating film on which this line / space pattern was formed was observed using an optical microscope and a scanning electron microscope S-4800 manufactured by Hitachi High-Technologies Corporation. Regardless of the temperature at which the resist underlayer film was baked, the unexposed areas of the resist underlayer film dissolved along with the photoresist, the line / space pattern of 15 μm or more was adhered, and no residue or remaining film was observed in the openings.

[0080] (Evaluation 14) to (Evaluation 15) <Evaluation in the case where a resist underlayer film made of a composition for forming a resist underlayer film was provided> Compositions [9] to

[10] for forming a resist underlayer film listed in Table 3 were evaluated in the same manner as in Evaluation 13. The results of Evaluations 13 to 15 are shown in Table 5 below.

[0081] The pattern evaluation criteria, residue evaluation criteria, and solvent resistance evaluation criteria in Table 5 are the same as those in Table 4.

[0082]

[0039] As shown in the above examples, a resist underlayer film is obtained by using a composition for forming a resist underlayer film that can change the developer dissolution rate of the resist underlayer film in a developer, and baking the composition for forming a resist underlayer film at a suitable temperature that results in the desired developer dissolution rate. The resist underlayer film exhibits solvent resistance to the solvent contained in the resist material for forming a colored resist film, and exhibits solubility in an alkaline developer for the colored resist film. When such a resist underlayer film is disposed between a substrate and a colored resist film and the colored resist is patterned, no developer-insoluble colorant residue is generated on the substrate between adjacent resist patterns, the resist patterns are not easily peeled off from the substrate, and a good colored resist pattern can be formed.

[0083] 1 Substrate 2 Resist underlayer film 3 Colored resist film 4 Mask

Claims

1. A composition for forming a resist underlayer film for forming a resist underlayer film disposed between a substrate and a colored resist film, the composition for forming a resist underlayer film comprising an alkali-soluble resin and a solvent, and the resist underlayer film formed by baking the composition for forming a resist underlayer film exhibits solvent resistance to a solvent contained in a resist material for forming the colored resist film and exhibits solubility in an alkaline developer for the colored resist film.

2. The composition for forming a resist underlayer film according to claim 1, wherein the alkali-soluble resin is a polyamic acid.

3. The composition for forming a resist underlayer film according to claim 1, which contains a crosslinking agent.

4. The composition for forming a resist underlayer film according to claim 3, wherein the crosslinking agent is an epoxy compound.

5. The composition for forming a resist underlayer film according to claim 1, which contains a development speed adjuster.

6. The composition for forming a resist underlayer film according to claim 5, wherein the development speed adjuster is a compound containing a phenolic hydroxyl group or a carboxyl group.

7. A resist underlayer film, which is a cured film of the composition for forming a resist underlayer film according to any one of claims 1 to 6.

8. The resist underlayer film according to claim 7, which is non-photosensitive.

9. A laminate comprising a substrate, the resist underlayer film according to claim 7, and a colored resist film.

10. The laminate according to claim 9, wherein the temperature at which the resist underlayer film develops solvent resistance to a solvent contained in a resist material for forming the colored resist film is set lower than the temperature at which the resist underlayer film becomes insolubilized in an alkaline developer for the colored resist film.

11. A method for forming a colored resist pattern, comprising the steps of: applying a composition for forming a resist underlayer film according to any one of claims 1 to 6 onto a substrate, and baking the composition to form a resist underlayer film; forming a colored resist film on the resist underlayer film; and exposing the colored resist film to light, and developing the colored resist film in a desired portion and the resist underlayer film formed under the desired portion of the colored resist film, thereby obtaining a colored resist pattern.

12. The method for forming a colored resist pattern according to claim 11, wherein the baking performed when forming the resist underlayer film is performed under temperature conditions between a temperature at which the resist underlayer film exhibits solvent resistance to a solvent contained in a resist material for forming the colored resist film and a temperature at which the resist underlayer film becomes insolubilized in an alkaline developer.

13. The colored resist pattern forming method according to claim 11, wherein the colored resist film is formed using a pigment-dispersed resist material.

14. The colored resist pattern forming method according to claim 11, wherein the colored resist film is formed using a metal oxide particle dispersed resist material.

15. The laminate according to claim 9, wherein the resist underlayer film and the colored resist film are patterned.

16. A self-luminous display element or liquid crystal display element comprising the laminate according to claim 15.

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