Photosensitive resin composition and method for forming a cured relief pattern

Abstract

To provide a photosensitive polyimide precursor composition with low i-line absorbance, high Tg, and high resistance to HAST (High Temperature and High Humidity Stress Test). [Solution] (A) General formula (A-1) below A photosensitive resin composition comprising (B) a polyimide precursor having a structure represented by formula (A-1), (B) a photopolymerization initiator, (C) a thermobase generator, and (D) a solvent.

Description

[Technical Field]

[0001] The present invention relates to a photosensitive resin composition and a method for forming a cured relief pattern. [Background technology]

[0002] Polyimide resins have traditionally been used as insulating materials for electronic components, passivation films for semiconductor devices, surface protective films, and interlayer insulating films. Polyimide resins possess excellent heat resistance, electrical properties, and mechanical properties, making them suitable for the above applications. In particular, those provided in the form of photosensitive polyimide precursor compositions can easily form heat-resistant cured relief pattern coatings, and significantly reduce the process time compared to non-photosensitive polyimide materials (Non-Patent Literature 1).

[0003] Photosensitive polyimide precursor compositions are required to have, for example, high resolution capable of forming fine patterns, and high heat resistance so that the adhesion between the cured film and the wiring is not impaired even at high temperatures. To improve the resolution of a photosensitive polyimide precursor composition, it is necessary to lower the absorbance of the composition (improve light transmittance) so that the ultraviolet light irradiated during exposure reaches the bottom surface of the composition film. In particular, the absorbance of the photosensitive polyimide precursor composition to the i-line (wavelength 365 nm) used for exposure is required to be low. Furthermore, in order to improve the heat resistance of the cured film, it is necessary to improve the glass transition temperature (Tg) of the polyimide resin. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] Japan Polyimide and Aromatic Polymer Research Association (ed.), "Revised Edition: Latest Polyimides - Fundamentals and Applications," published by NTS Corporation, August 2010, p. 330. [Overview of the project] [Problems that the invention aims to solve]

[0005] The absorbance of a photosensitive polyimide precursor composition is primarily determined by the absorbance of the polyimide precursor contained in the composition. The absorbance of the polyimide precursor is thought to depend, for example, on the HOMO-LUMO gap and the structure of the main chain of the starting materials, tetracarboxylic dianhydride and diamine. For example, polyimide precursors obtained from weakly acidic tetracarboxylic dianhydrides and weakly basic diamines are thought to have low absorbance. However, such tetracarboxylic dianhydrides and diamines are poorly reactive, making the synthesis of polyimide precursors difficult. Furthermore, polyimide precursors with a bent structure introduced into the main chain are thought to have low absorbance. However, the cured product (polyimide) of such polyimide precursors is thought to have a low Tg.

[0006] Furthermore, in recent years, the High Accelerated Stress Test (HAST) has been introduced as a reliability test for electronic equipment. HAST predicts the lifespan under normal operating conditions by observing the degradation of materials after they have been subjected to high temperature and high humidity conditions more severe than those of normal operating conditions for a predetermined period of time.

[0007] In this context, the object of the present invention is to provide a photosensitive polyimide precursor composition with low i-line absorbance, high Tg, and high HAST resistance, and a method for forming a cured relief pattern using the same. [Means for solving the problem]

[0008] In view of the above problems, the present inventors conducted diligent studies and found that by using an acidic dianhydride containing an alicyclic skeleton as a polyimide precursor, and by using it in combination with a thermobase generator, a photosensitive polyimide precursor composition with low i-line absorbance, high Tg, and high HAST resistance can be obtained, thus completing the present invention. That is, the present invention is as follows.

[0009] Appearance 1: (A) The following general formula (A-1) [ka] A polyimide precursor having the structure represented by formula (A-1), where X1 is a tetravalent organic group, Y1 is a divalent organic group, n1 is the number of repeating units and is an integer from 2 to 150, R1 and R2 are each independently a hydrogen atom or a monovalent organic group, and at least one part of X1 includes an alicyclic skeleton. (B) Photopolymerization initiator, (C) Thermobase generator, and (D) Solvent A photosensitive resin composition containing [the specified element]. 《Aspect 2》X1 in the above formula (A-1) is the following formula (X1-1) to (X1-11) [ka] A photosensitive resin composition according to Embodiment 1, comprising one or more structures selected from each of the structures represented by {R3 to R6 in formula (X1-1) are each independently a hydrogen atom or an organic group having 1 to 4 carbon atoms}. <Aspect 3> The photosensitive resin composition according to aspect 1, wherein at least one of R1 and R2 in formula (A-1) is a monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms. <Aspect 4> The photosensitive resin composition according to aspect 2, wherein at least one of R1 and R2 in formula (A-1) is a monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms. <Aspect 5> The photosensitive resin composition according to any one of aspects 1 to 4, wherein the (C) thermobase generating agent is a urea-type thermobase generating agent or a carbonate-type thermobase generating agent. <Aspect 6> The photosensitive resin composition according to any one of aspects 1 to 4, wherein the amount of (C) the thermal base generating agent is 1 part by mass or more and 50 parts by mass or less per 100 parts by mass of the (A) polyimide precursor. <Aspect 7> A photosensitive resin composition according to any one of aspects 1 to 4, used for forming an interlayer insulating film. 《Aspect 8》(1) Applying the photosensitive resin composition according to any one of Aspects 1 to 4 onto a substrate to form a photosensitive resin layer on the substrate; (2) Exposing the photosensitive resin layer; (3) Developing the exposed photosensitive resin layer to form a relief pattern, and (4) Heat-treating the relief pattern to form a cured relief pattern A method for forming a cured relief pattern, comprising the above steps. 《Aspect 9》A polyimide film which is a cured product of the photosensitive resin composition according to any one of Aspects 1 to 4. 《Aspect 10》The polyimide film according to Aspect 9, which is an interlayer insulating film.

Advantages of the Invention

[0010] According to the present invention, there are provided a photosensitive polyimide precursor composition having a low i-line absorbance, a high Tg, and high HAST resistance, and a method for forming a cured relief pattern using the same.

Modes for Carrying Out the Invention

[0011] Hereinafter, modes for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. Throughout this specification, when a structure represented by the same reference numeral in a general formula exists in plural in a molecule, they may be the same as each other or different from each other. The present invention is not limited to the following present embodiment, and various modifications may be made and implemented within the scope of the gist thereof.

[0012] 《Photosensitive Resin Composition》 The photosensitive resin composition of the present embodiment is (A) The following general formula (A-1)

[0013]

Chemical Formula

[0014] A polyimide precursor having the structure represented by formula (A-1), where X1 is a tetravalent organic group, Y1 is a divalent organic group, n1 is the number of repeating units and is an integer from 2 to 150, R1 and R2 are each independently a hydrogen atom or a monovalent organic group, and at least one part of X1 includes an alicyclic skeleton. (B) Photopolymerization initiator, (C) Thermobase generator, and (D) Solvent Includes.

[0015] The photosensitive resin composition of this embodiment may optionally contain any component other than (A) a polyimide precursor, (B) a photopolymerization initiator, (C) a thermobase generator, and (D) a solvent. The optional component may be one or more selected from, for example, (A) a resin other than the polyimide precursor (other resins), a crosslinking agent, a sensitizer, an adhesion aid, a thermal polymerization inhibitor, a discoloration inhibitor, a heat resistance improver, etc.

[0016] (A) Polyimide precursor In this embodiment, (A) the polyimide precursor is The following general formula (A-1)

[0017] [ka]

[0018] The structure is represented by {Formula (A-1), where X1 is a tetravalent organic group, Y1 is a divalent organic group, n1 is the number of repeating units and is an integer between 2 and 150, and R1 and R2 are each independently a hydrogen atom or a monovalent organic group, and at least one part of X1 includes an alicyclic skeleton.}

[0019] It has been conventionally known that compositions containing a polyimide precursor in which at least one part of X1 in formula (A-1) contains an alicyclic skeleton have low i-line absorbance, and that the Tg of the polyimide precursor can be improved by adjusting the remaining structure. However, in the prior art, it was not possible to obtain a cured film with high HAST resistance from compositions containing a polyimide precursor containing an alicyclic skeleton. However, in the present invention, by using a polyimide precursor containing an alicyclic skeleton in combination with a thermobase generator, it has become possible to provide a photosensitive polyimide precursor composition with low i-line absorbance, high Tg, and high HAST resistance.

[0020] In formula (A-1), X1 is a tetravalent organic group, and at least one of X1 contains an alicyclic skeleton. "At least one of X1 contains an alicyclic skeleton" means that at least one of the X1 groups contained in one polyimide precursor molecule has a structure that includes an alicyclic skeleton. (A) The proportion of X1 containing an alicyclic skeleton among the total X1 in the polyimide precursor may be 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, 90 mol% or more, or 95 mol% or more, or 100 mol%.

[0021] In formula (A-1), X1 is bonded to a -COOR1 group, a -COOR2 group, and two -CONH- groups. Here, the -COOR1 group and one of the -CONH- groups may each be bonded to two carbon atoms adjacent to each other in X1, and the -COOR2 group and the other -CONH- group may each be bonded to two other carbon atoms adjacent to each other in X1.

[0022] In equation (A-1), X1 is, from the perspective of improving HAST resistance, for example, as shown in equations (X1-1) to (X1-11) below.

[0023] [ka] {In formula (X1-1), R3 to R6 are each independently a hydrogen atom or an organic group having 1 to 4 carbon atoms.} and may be one or more selected from the structures represented by each of these formulas.

[0024] In formula (A-1), X1 only needs to have a structure that includes an alicyclic skeleton in at least one part, and the remaining part of X1 may be a tetravalent organic group that does not include an alicyclic skeleton. From the viewpoint of improving the Tg of the composition, X1 that does not include an alicyclic skeleton may be a group represented by each of the following general formulas (X1-12) to (X1-14), and may be one or more selected from these.

[0025] [ka]

[0026] [ka]

[0027] [ka]

[0028] {In formulas (X1-12) to (X1-14), R is a group selected from the group consisting of hydrogen atoms, fluorine atoms, monovalent hydrocarbon groups having 1 to 10 carbon atoms, and monovalent fluorine-containing hydrocarbon groups having 1 to 10 carbon atoms; l is an integer selected from 0 to 2; m is an integer selected from 0 to 3; and n is an integer selected from 0 to 4.}

[0029] In formula (A-1), X1 is derived from the tetracarboxylic dianhydride used in the synthesis of the (A) polyimide precursor. As tetracarboxylic dianhydrides that lead to X1 represented by (X1-1) to (X1-11), for example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, tricyclo[6.4.0.0 2,7] Dodecane-1,8:2,7-tetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride (CHDA), bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic dianhydride, bicyclo[2,2,2]octo-7-ene-2,3,5,6-tetracarboxylic dianhydride (BCD), norbornane-2- Examples include spiro-α-cyclopentanone-α′-spiro-2″-norbornane-5,5″,6,6″-tetracarboxylic dianhydride (CpODA), 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexen-1,2-carboxylic dianhydride, and 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-carboxylic dianhydride.

[0030] Examples of tetracarboxylic dianhydrides that lead to X1, represented by (X1-12) to (X1-14), include pyromellitic anhydride, diphenyl ether-3,3',4,4'-tetracarboxylic dianhydride, benzophenone-3,3',4,4'-tetracarboxylic dianhydride, biphenyl-3,3',4,4'-tetracarboxylic dianhydride, 9,9-bis(3,4-dicarboxyphenyl)fluorene dianhydride, bis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylic acid)1,4-phenylene, diphenylsulfone-3,3',4,4'-tetracarboxylic dianhydride, diphenylmethane-3,3',4,4'-tetracarboxylic dianhydride, 2,2-bis(3,4-phthalic anhydride)propane, and 2,2-bis(3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane.

[0031] In formula (A-1), Y1 is a divalent organic group, and from the viewpoint of improving the Tg of the composition, the groups represented by the following general formulas (Y1-1) to (Y1-3) are listed, and one or more selected from these may be included.

[0032] [ka]

[0033] [ka]

[0034] [ka]

[0035] {In formulas (Y1-1) to (Y1-3), R is a group selected from the group consisting of a hydrogen atom, a fluorine atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, and a monovalent fluorine-containing hydrocarbon group having 1 to 10 carbon atoms.}

[0036] In formula (A-1), Y1 is derived from the diamine used in the synthesis of the (A) polyimide precursor. Examples of diamines that lead to Y1, represented by (Y1-1) to (Y1-3), include 2,2'-dimethyl-4,4-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminobenzanilide, 1,3-bis(aminophenoxy)propane, 1,2-bis[2-(4-aminophenoxy)ethoxy]ethane, 9,9-bis(4-aminophenyl)fluorene, and 5(6)-(4-aminomethyl)-1,3,3-trimethyl Examples include thylindan, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 2,2-bis(4-aminophenoxyphenyl)propane, 2,2-bis(4-aminophenoxyphenyl)hexafluoropropane, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, p-aminobenzoic acid-p-aminophenyl ester, p-phenylenediamine, m-phenylenediamine, etc.

[0037] In formula (A-1), R1 and R2 are each independently a hydrogen atom or a monovalent organic group. Here, at least one of R1 and R2 may be a monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms. This monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms may be, for example, a group represented by the following general formula (R-1).

[0038] [ka]

[0039] {In formula (R-1), R7, R8, and R9 are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and m1 is an integer from 1 to 10.} In (R-1), m1 is preferably an integer between 1 and 5, and more preferably an integer between 1 and 3. The group represented by the above general formula (R-1) is preferably the group represented by the following general formula (R-2).

[0040] [ka]

[0041] {In equation (R-2), R7, R8, and R9 have the same meanings as R7, R8, and R9 in equation (R-1), respectively.} In formulas (R-1) and (R-2), the monovalent organic groups having 1 to 3 carbon atoms in R5, R6, and R7 specifically include the methyl group, ethyl group, n-propyl group, and isopropyl group. R5 is preferably a hydrogen atom or a methyl group, and R6 and R7 are preferably hydrogen atoms, respectively.

[0042] From the viewpoint of achieving higher resolution in the resulting photosensitive resin composition, the proportion of monovalent organic groups having radical polymerizable groups with 2 to 40 carbon atoms in formula (A-1) is preferably 30 mol% or more, more preferably 50% or more, particularly preferably 70 mol% or more, and may also be 100 mol% based on the total number of moles of R3 and R4 in formula (A-1).

[0043] If R1 and R2 are monovalent organic groups other than monovalent organic groups having radical polymerizable groups, R1 and R2 may each be independently a C1-C4 alkyl group, preferably a methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, or t-butyl group.

[0044] (A) A polyimide precursor can be prepared, for example, by reacting a tetracarboxylic dianhydride having the tetravalent organic group X1 described above with an alcohol having a radical polymerizable group and optionally another alcohol to prepare a partially esterified tetracarboxylic acid (hereinafter referred to as "acid / ester"), and then by amide polycondensation of this acid / ester with a diamine having the divalent organic group Y1 described above. The reaction to prepare an acid / ester by reacting a tetracarboxylic dianhydride having a tetravalent organic group X1 with an alcohol having a radical polymerizable group, and the amide polycondensation of the obtained acid / ester with a diamine having a divalent organic group Y1, are preferably carried out in a suitable solvent. Typically, the acid / ester mixture is prepared in a suitable solvent, and the resulting reaction mixture is then mixed with a diamine, followed by amide polycondensation.

[0045] (A) Alcohols having radical polymerizable groups used in the preparation of polyimide precursors include, specifically, 2-hydroxyethyl methacrylate, 2-acryloyloxyethyl alcohol, 1-acryloyloxy-3-propyl alcohol, 2-acrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-butoxypropyl acrylate, 2-hydroxy-3-t-butoxypropyl acrylate, 2-hydroxy-3-cyclohexyloxypropyl acrylate, 2-methacryloyloxyethyl alcohol, 1-methacryloyloxy-3-propyl Examples include propyl alcohol, 2-methacrylamidoethyl alcohol, methylol vinyl ketone, 2-hydroxyethyl vinyl ketone, 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-t-butoxypropyl methacrylate, 2-hydroxy-3-cyclohexyloxypropyl methacrylate, glycerol diacrylate, 1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol, glycerol dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, etc., and one or more selected from these can be used. However, the alcohols having radical polymerizable groups used in the preparation of (A) polyimide precursors are not limited to the above examples.

[0046] The proportion of alcohols having radical polymerizable groups may be appropriately set according to the proportion of monovalent organic groups having radical polymerizable groups in the polyimide precursor (A).

[0047] (A) Other alcohols used in the preparation of polyimide precursors include, for example, methanol, ethanol, n-propanol, isopropanol, n-butanol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, neopentyl alcohol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 3-octanol, 1-nonanol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, benzyl alcohol, etc., and one or more selected from these may be used.

[0048] The above-mentioned tetracarboxylic dianhydride and an alcohol having a radical polymerizable group are reacted in the presence of a suitable basic catalyst (e.g., pyridine) at a temperature of preferably 20 to 50°C for preferably 4 to 10 hours under stirring to obtain an acid / ester compound.

[0049] The amide condensation of the above acid / ester compound with the diamine having a divalent organic group Y1 is carried out in the presence of a suitable dehydrating condensation agent, preferably under ice cooling. Typically, a solution containing an acid / ester compound is treated with a dehydrating condensation agent under ice cooling to convert the acid / ester compound into a polyacid anhydride, and then a diamine having a divalent organic group Y1 is added and the reaction is carried out further to obtain the desired (A) polyimide precursor. Examples of dehydration condensation agents include dicyclohexylcarbodiimide, 1-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline, 1,1-carbonyldioxy-di-1,2,3-benzotriazole, and N,N'-disuccinimidyl carbonate. Depending on the reactivity of the substrate, 1-hydroxybenzotriazole or the like may be used instead of the dehydrating condensation agent.

[0050] Alternatively, the desired (A) polyimide precursor (polyamic acid ester) can also be obtained by acid-chloridizing the acid portion of the acid / ester product with thionyl chloride or the like, and then reacting it with a diamine in the presence of a base such as pyridine.

[0051] As described above, the reaction to prepare the acid / ester by reacting a tetracarboxylic dianhydride with an alcohol, and the amide polycondensation of the acid / ester with a diamine, are preferably carried out in a suitable solvent. The solvent used here is preferably one that can uniformly dissolve or disperse the tetracarboxylic dianhydride, alcohol, acid / ester compound, and (A) polyimide precursor in order to carry out the reaction efficiently in a homogeneous system. Specific examples of solvents include, for instance, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, N-ethyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, dimethyl sulfoxide, tetramethylurea, gamma-butyrolactone, 3-methoxy-N,N-dipropanamide, 3-butoxy-N,N-dipropanamide, ketones, esters, lactones, ethers, halogenated hydrocarbons, hydrocarbons, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, methyl acetate, ethyl acetate, butyl acetate, diethyl oxalate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, chlorobenzene, o-dichlorobenzene, hexane, heptane, benzene, toluene, xylene, etc., and one or more selected from these may be used.

[0052] As described above, the desired (A) polyimide precursor is obtained, typically in solution in the reaction mixture. The obtained (A) polyimide precursor is, if necessary, filtered to remove water-absorbing by-products of the dehydrating condensing agent present in the reaction solution, and then precipitated with a poor solvent to recover as a crude product. Suitable poor solvents include, for example, water, aliphatic lower alcohols, or mixtures thereof. The crude product can be purified by repeated redissolution and reprecipitation operations, and then vacuum-dried to isolate the target (A) polyimide precursor. To improve the degree of purification, a solution of this polymer may be passed through a column packed with an anion exchange resin, a cation exchange resin, or both of these swollen with a suitable organic solvent, to remove ionic impurities.

[0053] In this embodiment, (A) polyimide precursor may be used alone or as a mixture of two or more types.

[0054] (B) Photopolymerization initiator In this embodiment, (B) the photopolymerization initiator is preferably a photoradical polymerization initiator. Examples of photoradical polymerization initiators include, Benzophenone compounds such as benzophenone, o-methyl benzoylbenzoate, 4-benzoyl-4'-methyldiphenyl ketone, dibenzyl ketone, and fluorenone; Acetophenone compounds such as 2,2'-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, and 1-hydroxycyclohexylphenyl ketone; Thioxanthone compounds such as thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, and diethylthioxanthone; Benzyl compounds such as benzyl, benzyldimethyl ketal, and benzyl-β-methoxyethyl acetal; Benzoin compounds such as benzoin and benzoin methyl ether; Oxime compounds such as 1-phenyl-1,2-butanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-benzoyl)oxime, 1,3-diphenylpropanetrione-2-(o-ethoxycarbonyl)oxime, and 1-phenyl-3-ethoxypropanetrione-2-(o-benzoyl)oxime; N-arylglycine compounds such as N-phenylglycine; In addition to peroxides such as benzoyl perchloride, Examples include aromatic biimidazole compounds and titanocene compounds, and one or more selected from these may be used.

[0055] The photopolymerization initiator (B) in this embodiment is not limited to the above examples. In this embodiment, (B) as the photopolymerization initiator, an oxime compound is preferred from the viewpoint of high photosensitivity.

[0056] The amount of (B) photopolymerization initiator in the photosensitive resin composition of this embodiment is preferably 0.1 parts by mass or more and 30 parts by mass or less per 100 parts by mass of (A) polyimide precursor. From the viewpoint of ensuring the photosensitivity or patternability of the resulting photosensitive resin composition, the amount of (B) is preferably 0.1 parts by mass or more per 100 parts by mass of (A) polyimide precursor, and from the viewpoint of improving the physical properties of the resulting cured film, it is preferably 30 parts by mass or less per 100 parts by mass of (A) polyimide precursor. The amount of (B) photopolymerization initiator is more preferably 0.5 parts by mass or more and 20 parts by mass or less, more preferably 1 part by mass or more and 15 parts by mass or less, more preferably 2 parts by mass or more and 10 parts by mass or less, and particularly preferably 3 parts by mass or more and 8 parts by mass or less per 100 parts by mass of (A) polyimide precursor.

[0057] (C) Thermal base generator In this embodiment, (C) the thermobase generating agent is a compound that generates a precipitate when heated to 40°C or higher. By incorporating (A) a polyimide precursor having an alicyclic skeleton and (C) a thermobase generator into the photosensitive resin composition of this embodiment, it is possible to improve the HAST resistance of the resulting cured film. In this embodiment, (C) the thermal base generator may be selected from, for example, ion-pair type thermal base generators, dicarboxylic acid type thermal base generators, urea type thermal base generators, carbonate type thermal base generators, and the like.

[0058] The ion-pair type thermobase generator may be, for example, a compound represented by the following formula (CI-1).

[0059] [ka]

[0060] The dicarboxylic acid-type thermobase generator may be, for example, a compound represented by the following formula (CD-1).

[0061] [ka]

[0062] Preferably, the urea-type thermobase generator is a compound obtained by reacting an amine with an isocyanate to convert the amino group of the amine into a urea bond for protection. The urea-type thermobase generator does not exhibit basicity at room temperature (e.g., 23°C), but when heated to 40°C or higher, the protecting group (isocyanate) is removed, the amino group is regenerated, and basicity is exhibited. Here, as the amine, for example, diethanolamine, dihexylamine, dibutylamine, etc. may be used. Examples of isocyanates that may be used include ethyl isocyanate, butyl isocyanate, hexyl isocyanate, 2-isocyanatoethyl methacrylate (MOI), 2-isocyanatoethyl acrylate, 2-(2-methacryloyloxyethyloxy)ethyl isocyanate, and 1,1-(bisacryloyloxymethyl)ethyl isocyanate. A preferred example of a urea-type thermobase generator is a compound represented by the following formula (CU-1).

[0063] [ka]

[0064] {In formula (CU-1), R 10 ~R 12 Each of these is independently a hydrogen atom or an organic group having 1 to 12 carbon atoms, and R 11 and R 12 These atoms may be bonded together to form a cyclic structure containing nitrogen atoms. In equation (CU-1), R 11 and R 12 Preferably, at least one of them is not a hydrogen atom. Specific examples of compounds represented by (CU-1) include the compounds represented by (CU-2) and (CU-3) below.

[0065] [ka]

[0066] [ka]

[0067] The carbonate-type thermal base generator is a compound in which an amine is reacted with a carbonate to convert the amino group of the amine into a urethane bond for protection. The carbonate-type thermal base generator does not exhibit basicity at room temperature (e.g., 23 °C), but when heated to 40 °C or higher, the protecting group (carbonate) is removed and the amino group is regenerated, thereby exhibiting basicity. Here, as the amine, for example, imidazole or the like is preferably used. Examples of the carbonate include di-tert-butyl dicarbonate and the like. The carbonate-type thermal base generator may be, for example, a compound represented by the following formula (CC-1).

[0068]

Chemical formula

[0069] {In formula (CC-1), R 13 and R 14 are each independently a hydrogen atom or an organic group having 1 to 12 carbon atoms, and R 13 and R 14 may be bonded to each other to form a cyclic structure containing a nitrogen atom.} In formula (CC-1), it is preferable that at least one of R 13 and R 14 is not a hydrogen atom.

[0070] In this embodiment, as the (C) thermal base generator, from the viewpoint of improving the viscosity stability of the photosensitive resin composition, it is preferable to use a urea-type thermal base generator or a carbonate-type thermal base generator.

[0071] In the photosensitive resin composition of this embodiment, the amount of (C) thermal base generator blended is preferably 1 to 50 parts by mass, more preferably 3 to 40 parts by mass, even more preferably 5 to 30 parts by mass, and particularly preferably 10 to 25 parts by mass, per 100 parts by mass of (A) polyimide precursor. By adjusting the amount of (C) thermal base generator blended within this range, the resulting cured film will have an excellent balance between HAST resistance and thermal expansion coefficient.

[0072] (D) Solvent In the photosensitive resin composition of this embodiment, the solvent (D) is preferably a polar organic solvent from the viewpoint of having high solubility for the polyimide precursor (A). Specific examples of the solvent (D) in this embodiment include N,N-dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylacetamide, dimethyl sulfoxide, diethylene glycol dimethyl ether, cyclopentanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, 3-methoxy-N,N-dipropanamide, 3-butoxy-N,N-dipropanamide, ethyl lactate, methyl lactate, propyl lactate, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, 2-octanone, etc., and one or more selected from these may be used.

[0073] The amount of solvent (D) in the photosensitive resin composition of this embodiment may be set appropriately depending on the method of coating the composition, the desired film thickness, etc. The amount of solvent (D) can be 30 parts by mass or more and 1,500 parts by mass or less per 100 parts by mass of polyimide precursor (A), preferably 50 parts by mass or more and 1,000 parts by mass or less, and more preferably 100 parts by mass or more and 500 parts by mass or less.

[0074] <Optional ingredients> (Other resins) The photosensitive resin composition of this embodiment may also contain resins other than (A) the polyimide precursor (other resins). Other resins include, for example, polyimide precursors that do not fall under (A) polyimide precursor in the present invention (such as polyamic acid and polyamic acid esters), polyimides, polyoxazoles, polyoxazole precursors, phenolic resins, polyamides, epoxy resins, siloxane resins, acrylic resins, and the like. The amount of other resins blended in the photosensitive resin composition of this embodiment may be limited to a range that does not diminish the effects of the present invention. For example, per 100 parts by mass of (A) polyimide precursor, the amount may be 20 parts by mass or less, 10 parts by mass or less, 5 parts by mass or less, or 1 part by mass or less, or even 0 parts by mass. When other resins are added to the photosensitive resin composition, the amount added may be 0.01 parts by mass or more per 100 parts by mass of the polyimide precursor (A).

[0075] (Crosslinking agent) The photosensitive resin composition of this embodiment may contain a solvent to improve the resolution of the composition. As a crosslinking agent, (meth)acrylate compounds with two or more functions are preferred, and (meth)acrylate compounds with two to six functions are particularly preferred. Crosslinking agents include, for example, (Poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, glycerol di(meth)acrylate, glycerol tri(meth)acrylate, silohexane di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, bisphenol A di(meth)acrylate, benzene tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, glycerol di(meth)acrylate, glycerol tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, etc.; and These ethylene oxide compounds, these propylene oxide adducts, etc. These are some examples.

[0076] The amount of crosslinking agent in the photosensitive resin composition of this embodiment may be 80 parts by mass or less, 60 parts by mass or less, 40 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 5 parts by mass or less, or 1 part by mass or less, or 0 parts by mass, per 100 parts by mass of (A) polyimide precursor. When a crosslinking agent is incorporated into a photosensitive resin composition, the amount of the crosslinking agent may be 1 part by mass or more per 100 parts by mass of (A) polyimide precursor, from the viewpoint of effectively improving the resolution of the composition.

[0077] (Sensitizer) The photosensitive resin composition of this embodiment may contain a sensitizer to improve the light sensitivity of the composition. Sensitizers include, for example, Michla's ketone, 4,4'-bis(diethylamino)benzophenone, 2,5-bis(4'-diethylaminobenzal)cyclopentane, 2,6-bis(4'-diethylaminobenzal)cyclohexanone, 2,6-bis(4'-diethylaminobenzal)-4-methylcyclohexanone, 4,4'-bis(dimethylamino)chalcone, 4,4'-bis(diethylamino)chalcone, p-dimethylaminocinnamyrideneindanone, p-dimethyl Aminobenzylidene indanone, 2-(p-dimethylaminophenylbiphenylene)-benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonaphthothiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-bis(4'-diethylaminobenzal)acetone, 3,3'-carbonyl-bis(7-diethylaminocoumarin), 3-acetyl-7-dimethylaminocoumarin Phosphorus, 3-ethoxycarbonyl-7-dimethylaminocoumarin, 3-benzyloxycarbonyl-7-dimethylaminocoumarin, 3-methoxycarbonyl-7-diethylaminocoumarin, 3-ethoxycarbonyl-7-diethylaminocoumarin, N-phenyl-N'-ethylethanolamine, N-phenyldiethanolamine, Np-tolyldiethanolamine, N-phenylethanolamine, 4-morpholinobenzophenone, isoamyl dimethylaminobenzoate, di Examples include isoamyl ethylaminobenzoate, 2-mercaptobenzimidazole, 1-phenyl-5-mercaptotetrazol, 2-mercaptobenzothiazole, 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-(p-dimethylaminostyryl)naphtho(1,2-d)thiazole, 2-(p-dimethylaminobenzoyl)styrene, and one or more selected from these may be used.

[0078] The amount of sensitizer in the photosensitive resin composition of this embodiment may be 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, or 10 parts by mass or less, or 0 parts by mass, per 100 parts by mass of (A) polyimide precursor. When a sensitizer is added to a photosensitive resin composition, the amount added may be 0.1 parts by mass or more per 100 parts by mass of (A) polyimide precursor, from the viewpoint of effectively improving the photosensitivity of the composition.

[0079] (Adhesion enhancer) The photosensitive resin composition of this embodiment may contain an adhesion promoter to improve the adhesion between the cured film and the substrate. The adhesion promoter may be selected from, for example, silane coupling agents, aluminum-based adhesion promoters, purine derivatives, etc., and one or more of these may be used.

[0080] Examples of silane coupling agents include γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, and N-(3-diethoxymethylsilane). Examples include lylpropyl)succinimide, N-[3-(triethoxysilyl)propyl]phthalamidic acid, benzophenone-3,3'-bis(N-[3-triethoxysilyl]propylamide)-4,4'-dicarboxylic acid, benzene-1,4-bis(N-[3-triethoxysilyl]propylamide)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propyl succinic anhydride, N-phenylaminopropyltrimethoxysilane, etc., and one or more selected from these may be used.

[0081] Examples of aluminum-based adhesion promoters include aluminum tris(ethyl acetate), aluminum tris(acetylacetonate), and ethyl acetate aluminum diisopropylate, and one or more selected from these may be used. Examples of purine derivatives include purine, adenine, guanine, 2,6-diaminopurine, 2-hydroxyadenine, 2-methyladenine, 2-fluoroadenine, 8-azaadenine, 8-azaguanine, and 8-azapurine, and one or more selected from these may be used.

[0082] The amount of adhesion aid in the photosensitive resin composition of this embodiment may be 25 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, or 5 parts by mass or less, or 0 parts by mass, per 100 parts by mass of (A) polyimide precursor. When a sensitizer is added to the photosensitive resin composition, the amount added may be 0.5 parts by mass or more per 100 parts by mass of (A) polyimide precursor, from the viewpoint of effectively improving the adhesion between the cured film and the substrate.

[0083] (Thermal polymerization inhibitor) The photosensitive resin composition of this embodiment may contain a thermal polymerization inhibitor to improve the stability of the composition's viscosity and photosensitivity when the composition is stored for a long period of time. The thermal polymerization inhibitor may be, for example, a nitrosamine compound, a phenol derivative, a hydroquinone derivative, a hydroxyquinoline derivative, a chelating agent, an ammonium salt, or the like.

[0084] (Discoloration inhibitor) The photosensitive resin composition of this embodiment may contain an adhesion aid or a discoloration inhibitor to suppress discoloration of the substrate. The discoloration inhibitor may be, for example, an azole compound or a hindered phenol compound.

[0085] (Heat resistance improver) The photosensitive resin composition of this embodiment may contain a heat resistance improver to further improve the HAST resistance of the resulting cured film. The cured film obtained from the photosensitive resin composition containing the heat resistance improver exhibits an extremely high rate of elongation retention before and after HAST. The heat resistance improver may be, for example, a titanium chelate having two or more alkoxyl groups, a tetraalkoxy titanium compound, a titanocene compound, a monoalkoxy titanium compound, a titanium oxide compound, a titanium tetraacetylacetonate compound, or a titanate-based coupling agent.

[0086] (Uses of photosensitive resin compositions) The photosensitive resin composition of this embodiment may be used, for example, to form passivation films, surface protective films, interlayer insulating films, redistribution insulating films for semiconductor substrates; protective films for flip-chip devices; and protective films for semiconductor devices having a bump structure. It is particularly suitable for forming interlayer insulating films for semiconductor substrates.

[0087] In addition to applications to semiconductor devices as described above, the photosensitive resin composition of the present invention is also useful for applications such as surface protective films, insulating films, and planarization films for TFT liquid crystal display elements and color filter elements; protrusions for MVA type liquid crystal display devices; interlayer insulating films for multilayer circuits; cover coats for flexible copper-clad plates; solder resist films; and liquid crystal alignment films.

[0088] Method for forming hardened relief patterns The present invention also provides a method for forming a cured relief pattern using the above-described photosensitive resin composition. The method for forming the hardened relief pattern in this embodiment is: (1) Applying the photosensitive resin composition of this embodiment onto a substrate to form a photosensitive resin layer on the substrate (photosensitive resin layer formation step), (2) Exposing the photosensitive resin layer (exposure process), (3) Developing the photosensitive resin layer after exposure to form a relief pattern (development step), and (4) Heat treatment of the relief pattern to form a hardened relief pattern. This is a method for forming a hardened relief pattern, including a heat treatment step. The following describes each step in the method for forming the hardened relief pattern of this embodiment.

[0089] <(1) Photosensitive resin layer formation process> In the photosensitive resin layer formation process, the photosensitive resin composition of this embodiment is applied to a substrate, and if necessary, then dried to form a photosensitive resin layer on the substrate. As for the coating method, methods that have been conventionally used for coating photosensitive resin compositions may be used. Specifically, for example, methods such as coating with a spin coater, bar coater, blade coater, curtain coater, screen printing machine, etc., and spray coating with a spray coater can be used.

[0090] The coating obtained as described above may be dried if necessary. Methods for drying the coating film include, for example, heat drying and vacuum drying. Heat drying may be performed, for example, by air drying, oven, or hot plate. When air-drying or heat-drying, it is preferable to dry at a temperature of 20°C to 140°C for 1 minute to 1 hour. As described above, a photosensitive resin layer is formed on the substrate. (2) Exposure process In the exposure process, the photosensitive resin layer formed above is exposed to light using an ultraviolet light source or the like. Exposure can be performed using, for example, an exposure device such as a contact aligner, mirror projection, or stepper. Exposure may be performed via a photomask or reticle having a pattern, or it may be performed directly without such a pattern.

[0091] After coating, if necessary, at least one of post-exposure baking (PEB) and pre-development baking may be performed at any temperature and for any duration to improve light sensitivity, etc. For both post-exposure baking and pre-development baking, the baking conditions are preferably a temperature of 40°C to 120°C and a duration of 10 seconds to 240 seconds.

[0092] <(3) Development process> In the development process, the unexposed portions of the photosensitive resin layer after exposure are developed and removed from the substrate, leaving a relief pattern composed of the exposed portions on the substrate. Conventional photoresist development methods can be used for development. Specifically, any method can be selected from, for example, the rotary spray method, the paddle method, or the immersion method with ultrasonic treatment. After development, if necessary, post-development baking may be performed using any combination of temperature and time for purposes such as adjusting the shape of the relief pattern.

[0093] The developer used for development is preferably, for example, a good solvent for the negative-type photosensitive resin composition, or a combination of the good solvent and a poor solvent. Preferred good solvents include, for example, N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and α-acetyl-γ-butyrolactone. Preferred poor solvents include, for example, toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, and water. The above good solvents and poor solvents may be used individually or as a mixture of two or more. When using a mixture of a good solvent and a poor solvent, it is preferable to adjust the ratio of the poor solvent to the good solvent according to the solubility of the polymer (unexposed (A) polyimide precursor) in the photosensitive resin composition. Furthermore, the photosensitive resin composition of this embodiment may be used for development with an organic solvent. In this case, (A) the polyimide precursor may be alkali-insoluble. Furthermore, the photosensitive resin composition of this embodiment may be used for development with a developer containing 90% or more, preferably 95% or more, of an organic solvent.

[0094] <Heat treatment process> In the heat treatment step, the relief pattern obtained in the development step is heated to dilute the photosensitive components and imidize the (A) polyimide precursor, thereby converting it into a cured relief pattern made of polyimide. Heating may be carried out, for example, by a hot plate, an oven, or a heating oven with a temperature programmable. The heat treatment may be carried out at a temperature of, for example, 150°C to 400°C, preferably 16°C to 300°C, more preferably 170°C to 250°C, and even more preferably 170°C to 200°C, for a period of time of, for example, 30 minutes to 5 hours. Air may be used as the atmospheric gas during the heat treatment, or an inert gas such as nitrogen or argon may be used.

[0095] Polyimide film According to another aspect of the present invention, a polyimide film is provided. The polyimide film of this embodiment is a cured product of the photosensitive resin composition of this embodiment, and is preferably formed using the photosensitive resin composition of this embodiment by the method for forming a cured relief pattern of this embodiment. The polyimide film of this embodiment may be, for example, a passivation film for a semiconductor substrate, a surface protective film, an interlayer insulating film, an insulating film for redistribution; a protective film for a flip-chip device; a protective film for a semiconductor device having a bump structure, etc., and is particularly suitable as an interlayer insulating film for a semiconductor substrate.

[0096] Semiconductor devices and display devices According to yet another aspect of the present invention, semiconductor devices and display devices are provided. The semiconductor device of this embodiment includes a substrate which is a semiconductor element and a polyimide film on the substrate, the polyimide film being a cured product of the photosensitive resin composition of this embodiment. The polyimide film in the semiconductor device of this embodiment may be, for example, a surface protective film, an interlayer insulating film, an insulating film for rewiring; a protective film for a flip-chip device; or a protective film for a semiconductor device having a bump structure. The display device of this embodiment includes a substrate which is a display element and a polyimide film on the substrate, the polyimide film being a cured product of the photosensitive resin composition of this embodiment. The polyimide film in the display device of this embodiment may be, for example, a surface protective film, insulating film, planarization film, etc. for TFT liquid crystal display elements and color filter elements; or a protrusion for an MVA type liquid crystal display device, etc. [Examples]

[0097] The present invention will be described below in the form of examples in order to provide a more detailed explanation of it. However, the present invention is not limited to the embodiments described below.

[0098] Evaluation Method The i-line absorbance, Tg, and HAST resistance in the following examples and comparative examples were measured by the methods described below.

[0099] (1) Measurement of i-line absorbance The resin compositions obtained in each example and comparative example were diluted with γ-butyrolactone to a polyimide precursor concentration of 0.1% by mass, and then packed into quartz cells with a thickness of 1 cm. The above-mentioned cell was loaded into the sample side of a UV-Vis spectrophotometer, model "UV-1800," manufactured by Shimadzu Corporation, and a similar quartz cell filled only with γ-butyrolactone was loaded into the reference side. Absorbance measurements were performed at a medium scan speed and a sampling pitch of 0.5 nm. The absorbance at a wavelength of 365 nm, corresponding to the i-line, was investigated. When the absorbance at 365 nm is less than 0.5, the i-line absorbance can be evaluated as good.

[0100] (2) Measurement of Tg Using a coater developer (manufactured by SEBACS SPE Services Co., Ltd., model name "SK-W60A-AVPQN"), the resin compositions obtained in each example and comparative example were spin-coated onto a 6-inch silicon wafer substrate having an aluminum (Al) vapor-deposited layer on its surface. At this time, the amount of the coating composition was adjusted so that the film thickness after curing was 7.5 μm. The obtained coating was pre-baked at 110°C for 4 minutes, then front-facing exposure for 59.9 seconds using a Canon Inc. exposure system, model "ghi-line stepper PLA-501F," followed by heat treatment at 230°C for 2 hours using a JTEKT Thermo Systems Corporation mini-batch type vertical system (vertical curing furnace), model "VF-2000B," to obtain a wafer with a polyimide film formed on one side. Using a dicing saw manufactured by Disco Corporation, model "DAD3350," the obtained polyimide-coated wafer was diced into 3 mm wide strips. The aluminum-deposited film was then dissolved by immersion in 10% by mass hydrochloric acid for 16 hours, and the polyimide film was peeled off and recovered.

[0101] The resulting polyimide exfoliated film was washed with water and dried at 50°C to be used as the sample for Tg evaluation. Using a thermomechanical analyzer, model "TMA-60," manufactured by Shimadzu Corporation, the TMA of samples obtained at temperatures ranging from room temperature to 450°C was measured, and a TMA chart was obtained. The inflection point of the obtained chart was defined as the glass transition temperature (Tg). When the Tg is 250°C or higher, the Tg can be considered good.

[0102] (3) Evaluation of HAST resistance Two wafers were manufactured with a polyimide film formed on one side, in the same manner as in "(2) Evaluation of Tg". One of the obtained wafers with polyimide films was immersed in 10% by mass hydrochloric acid for 16 hours without dicing to dissolve the Al-deposited film and remove and recover the initial polyimide film. Meanwhile, another wafer with a polyimide film obtained was subjected to heat treatment by passing it through a reflow oven manufactured by JTEKT Thermo Systems Co., Ltd., model "801-II-5Z," three times under conditions of 260°C and 200 mm / min. Furthermore, the heated polyimide film-coated wafer was subjected to moist heat treatment by being left to stand for one week under conditions of 130°C and 85% RH using a High Accelerated Life Test (HAST) apparatus manufactured by Hirayama Seisakusho Co., Ltd., model "PC-R8D." After the heat treatment and moist heat treatment (high accelerated stress test), the polyimide film-coated wafer was immersed in 10% by mass hydrochloric acid for 16 hours to dissolve the Al vapor-deposited film, and the polyimide film after the high accelerated stress test (HAST) was peeled off and recovered.

[0103] The elongation of the initial polyimide film and the polyimide film after HAST testing was measured. The elongation was measured using a Tensilon testing machine, model "UTM-II-20," manufactured by Orientec Co., Ltd., on a rectangular specimen measuring 3 mm x 50 mm, under conditions of a load of 2 kgf and a tensile speed of 40 mm / min. Then, the ratio of the elongation of the polyimide film after HAST to the progress of the initial polyimide film (elongation maintenance rate) was determined. When the elongation retention rate is 70% or higher, HAST resistance can be evaluated as extremely good, and when the elongation retention rate is between 30% and 70%, HAST resistance can be evaluated as good.

[0104] Manufacturing Example 1 (Synthesis of the thermal base generator "MOI-DEA") In a 300 mL three-necked flask, 10.5 g (0.10 mol) of diethanolamine (DEA) and 100 g of γ-butyrolactone were charged and stirred to form a solution. To this solution, 15.5 g (0.10 mol) of 2-isocyanatoethyl methacrylate (MOI) was added dropwise over 30 minutes under ice cooling. After the addition was complete, the reaction solution was heated to 23°C and stirred for 16 hours to obtain a solution containing the compound "MOI-DEA," in which the secondary amine bond of DEA was protected by forming a urea bond with the cyano group of MOI. The compound "MOI-DEA" is represented by the following formula. [ka]

[0105] Example 1 (1) Synthesis of polyimide precursors In a separable flask, 39.22 g (0.20 mol) of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (CBDA) and 54.14 g (0.42 mol) of 2-hydroxyethyl methacrylate (HEMA) were charged. Further, 125.00 g of γ-butyrolactone and 31.64 g (0.40 mol) of pyridine were added, and the mixture was stirred at room temperature for 16 hours to obtain the half-ester of 1,2,3,4-cyclobutanetetracarboxylic acid. Next, the reaction mixture was cooled to 0°C. A solution of 80.88 g (0.39 mol) of dicyclohexylcarbodiimide (DCC) dissolved in 80.88 g of γ-butyrolactone was added dropwise over 20 minutes under stirring. Then, while maintaining the temperature of the reaction mixture below 2°C, a solution of 36.41 g (0.18 mol) of 4,4'-diaminodiphenyl ether (DADPE) suspended in 109.22 g of γ-butyrolactone was added dropwise over 30 minutes under stirring.

[0106] Subsequently, the temperature of the reaction mixture was raised to room temperature, and stirring was continued at room temperature for another 4 hours. After 4 hours, 18.25 g of ethanol was added as a terminal encapsulant and the mixture was stirred for 30 minutes. The precipitate was then filtered off to obtain a reaction solution containing the polyimide precursor. The reaction solution was added to 3 L of ethanol, and the polyimide precursor was precipitated as a crude polymer and recovered. The crude polymer was redissolved in 600 g of N-methylpyrrolidone and then dropped into 6 L of water to reprecipitate. The resulting reprecipitate was collected and vacuum-dried at 40°C for 72 hours to obtain a powdered polyimide precursor.

[0107] (2) Preparation of photosensitive resin composition 7.00 g of the polyimide precursor obtained above, 0.28 g of 1,2-octanedione,-1-[(4-phenylthio)phenyl],-2-(O-benzoyloxime) (manufactured by BASF, product name "OXE-01") as a photopolymerization initiator, and A solution containing MOI-DEA synthesized in the above production example 1, equivalent to 1.4 g of MOI-DEA, used as a thermal base generator. The mixture was dissolved in 8.4 g of γ-butyrolactone and 2.1 g of dimethyl sulfoxide, and the photosensitive resin composition of Example 1 was prepared by filtering through a microfilter with a pore size of 1 μm.

[0108] (3) Evaluation The obtained photosensitive resin composition was evaluated using the method described above. The evaluation results are shown in Table 1.

[0109] Examples 2-6, and Comparative Examples 1 and 2 The polyimide precursor was synthesized and the photosensitive resin composition was prepared and evaluated in the same manner as in Example 1, except that the types and amounts of tetracarboxylic dianhydride and diamine used in "(1) Synthesis of Polyimide Precursor" and the types and amounts of photopolymerization initiator and thermobase generator used in "(2) Preparation of Photosensitive Resin Composition" were changed as shown in Table 1. The results are shown in Tables 1 and 2.

[0110] [Table 1]

[0111] [Table 2]

[0112] The abbreviations for the components in Tables 1 and 2 have the following meanings, respectively. <Tetracarboxylic acid dianhydride> CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride CpODA: norbornane-2-spiro-α-cyclopentanone-α′-spiro-2″ norbornane-5,5″,6,6″-tetracarboxylic dianhydride ( ODPA: Oxydiphthalic acid dianhydride

[0113] <Diamine> DADPE: 4,4'-diaminodiphenyl ether m-TB: 2,2'-dimethylbiphenyl-4,4'-diamine

[0114] <Photopolymerization initiator> OXE-01: 1,2-Octanedione,-1-[(4-phenylthio)phenyl],-2-(O-benzoyloxime) (manufactured by BASF, product name "OXE-01") PDO: 1,2-propanedione,-1-phenyl,-2-(O-ethoxycarbonyloxime) (manufactured by Arkema, Inc., product name "Sartomer PDO")

[0115] <Thermal base generator> MOI-DEA: The compound "MOI-DEA" synthesized as described above. N-BOC-imd: N-tert-butoxycarbonylimidazole, manufactured by Tokyo Chemical Industry Co., Ltd., product name "N-BOC Imidazole"

Claims

1. (A) The following general formula (A-1) 【Chemistry 1】 {In formula (A-1), X １ Y is a tetravalent organic group, １ is a divalent organic group, n １ R is the number of repeating units, which is an integer between 2 and 150. １ and R ２ Each is independently a hydrogen atom or a monovalent organic group, and the X １ At least one of these includes an alicyclic skeleton. A polyimide precursor having a structure represented by} (B) Photopolymerization initiator, (C) Thermal base generator, and (D) Solvent A photosensitive resin composition containing [the specified element].

2. X in the formula (A-1) １ is represented by the following formula (X １ -1) to (X １ -11) 【Chemistry 2】 {Formula (X １ -1) R in the middle ３ ~R ６ Each of these is independently a hydrogen atom or an organic group having 1 to 4 carbon atoms. The photosensitive resin composition according to claim 1, comprising one or more selected from the structures represented by each of the following.

3. In the above formula (A-1), R １ and R ２ The photosensitive resin composition according to claim 1, wherein at least one of the members is a monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms.

4. In the above formula (A-1), R １ and R ２ The photosensitive resin composition according to claim 2, wherein at least one of the is a monovalent organic group having a radical polymerizable group with 2 to 40 carbon atoms.

5. The photosensitive resin composition according to any one of claims 1 to 4, wherein the (C) thermobase generating agent is a urea-type thermobase generating agent or a carbonate-type thermobase generating agent.

6. The photosensitive resin composition according to any one of claims 1 to 4, wherein the amount of (C) the thermal base generating agent is 1 part by mass or more and 50 parts by mass or less per 100 parts by mass of the (A) polyimide precursor.

7. A photosensitive resin composition according to any one of claims 1 to 4, used for forming an interlayer insulating film.

8. (1) Applying the photosensitive resin composition according to any one of claims 1 to 4 onto a substrate to form a photosensitive resin layer on the substrate, (2) Exposing the photosensitive resin layer, (3) Develop the photosensitive resin layer after exposure to form a relief pattern, and (4) Heat-treating the relief pattern to form a hardened relief pattern. A method for forming a hardened relief pattern, including the method described above.

9. A polyimide film which is a cured product of the photosensitive resin composition according to any one of claims 1 to 4.

10. The polyimide film according to claim 9, which is an interlayer insulating film.

Images