Photosensitive resin composition, cured product, method for producing cured product, and electronic component

Abstract

The present invention addresses the problem of providing a photosensitive resin composition which has excellent pattern processability, which makes a cured film that exhibits good elongation, and which exhibits good elongation even after having undergone a package reliability test. In order to solve the problem, the present invention proposes a photosensitive resin composition containing: at least one polymer compound selected from the group consisting of polyamide, polyimide, polyamideimide, and polybenzoxazole having, as a partial structure, a diamine residue derived from an aromatic diamine having no phenolic hydroxyl group with an ionization potential of 6.78 eV or more; a cationically polymerizable compound; and a photocationic polymerization initiator.

Description

Photosensitive resin composition, cured product, method for producing the cured product, and electronic component

[0001] The present invention relates to a photosensitive resin composition that can be suitably used for surface protection films and interlayer insulating films in electronic components such as semiconductor elements, and insulating layers in organic electroluminescent devices, a cured product, a method for producing the cured product, and an electronic component.

[0002] Conventionally, polyimide-based materials and polybenzoxazole-based materials, which have excellent heat resistance, electrical insulation, and mechanical properties, have been widely used for surface protection films and interlayer insulating films of semiconductor elements. However, with the recent demand for higher density and performance of semiconductor elements, photosensitive materials are required for surface protection films and interlayer insulating films from the viewpoint of production efficiency.

[0003] In response to the recent demand for higher performance in electronic components, surface protection films and interlayer insulating films are required to be processed to have fine patterns and high aspect ratios. Furthermore, when resin compositions are used in applications such as electronic components, the films formed after heat curing remain as permanent films inside the devices, so the elongation of the cured films and the elongation of the cured films after package reliability testing are important.

[0004] Regarding means for forming fine patterns and high aspect ratios, a cationically curable photosensitive resin has been disclosed (Patent Document 1). Regarding means for improving the elongation of the cured film and improving reliability based on the presence or absence of cracks, there are photosensitive resins using diamines containing flexible alkylene oxides (Patent Document 2) and photosensitive resins using specific diamines (Patent Document 3).

[0005] International Publication No. 2021 / 059843 International Publication No. 2016 / 152794 Japanese Patent Application Laid-Open No. 2018-160665

[0006] However, the cationic curing photosensitive resin described in Patent Document 1 has a phenolic hydroxyl group in the diamine, and during curing, the phenolic hydroxyl group reacts with the cationically polymerizable compound, resulting in a problem of high crosslink density and poor elongation of the cured film. The cured film of the photosensitive resin described in Patent Document 2 exhibits a problem of deterioration of the alkylene oxide contained in the cured film after a package reliability test, resulting in a decrease in elongation after the reliability test. It has been found that when a resin using a specific diamine described in Patent Document 3 is applied to a cationic curing system, cationic curing is inhibited, resulting in a problem of making pattern processing impossible.

[0007] Therefore, an object of the present invention is to obtain a photosensitive resin composition that has excellent pattern processability, exhibits good elongation even after curing, and further exhibits good elongation even after the cured film has been subjected to a package reliability test.

[0008] The present invention and preferred embodiments thereof for solving the above problems comprise the following: [1] A photosensitive resin composition comprising at least one polymeric compound (component (A)) selected from the group consisting of polyamides, polyimides, polyamideimides, and polybenzoxazoles, each having, as a partial structure, a diamine residue derived from an aromatic diamine (aromatic diamine x1) having an ionization potential (Ip) of 6.78 eV or more and having no phenolic hydroxyl group; a cationically polymerizable compound (component (B)); and a photocationic polymerization initiator. [2] The photosensitive resin composition according to [1] above, wherein component (A) contains an aromatic carboxylic acid residue. [3] The photosensitive resin composition according to [1] or [2] above, wherein all or a portion of the aromatic diamine residue derived from the aromatic diamine residue x1 has, in its molecular structure, at least one bond selected from the group consisting of an ether bond, a sulfonyl bond, a ketone bond, and an ester bond. [4] The photosensitive resin composition according to any one of [1] to [3], wherein, when the total amount of diamine residues in component (A) is taken as 100 mol%, the content of diamine residues derived from aromatic diamine x1 is 55 to 100 mol%. [5] The photosensitive resin composition according to any one of [1] to [4], wherein, in component (A), both an aromatic diamine x1 having an Ip of 7.40 eV or more (aromatic diamine x1-1) and an aromatic diamine x1 having an Ip of 6.78 eV or more but less than 7.40 eV (aromatic diamine x1-2) are used. [6] The photosensitive resin composition according to [5], wherein, when the total amount of diamine residues in component (A) is taken as 100 mol%, the content of diamine residues derived from aromatic diamine x1-1 is 10 to 55 mol% and the content of diamine residues derived from aromatic diamine x1-2 is 45 to 90 mol%. [7] The photosensitive resin composition according to any one of [1] to [6] above, wherein all or part of the component (B) is an oxetane compound. [8] The photosensitive resin composition according to any one of [1] to [7] above, wherein the content of the component (B) is 80 parts by mass or more and 150 parts by mass or less, based on 100 parts by mass of the content of the component (A). [9] The photosensitive resin composition according to any one of [1] to [8] above, wherein all or part of the component (B) is a compound represented by formula (1).

[0009]

[0010] (A １ represents an alkylene group having 1 to 20 carbon atoms or a divalent hydrocarbon group having 3 to 20 carbon atoms and an aliphatic hydrocarbon ring; B １ , B ２ each independently represents an ether bond or an ester bond.)

[10] A cured product obtained by curing the photosensitive resin composition according to any one of [1] to [9] above.

[11] A method for producing a cured product using the photosensitive resin composition according to any one of [1] to [9] above, comprising the steps of: applying the photosensitive resin composition on a substrate and drying it to form a photosensitive resin composition film; exposing the photosensitive resin composition film; developing the exposed photosensitive resin composition film; and curing the developed photosensitive resin composition film.

[12] An electronic component comprising the cured product according to

[10] above.

[13] An electronic component in which the cured product according to

[10] above is arranged as an insulating film between wirings.

[0011] According to the present invention, it is possible to provide a photosensitive resin composition that has excellent pattern processability, exhibits good elongation even after curing, and further, the cured film exhibits good elongation even after undergoing a package reliability test.

[0012] The photosensitive resin composition of the present invention contains: (A) at least one polymer compound selected from the group consisting of polyamide, polyimide, polyamideimide, and polybenzoxazole, having, as a partial structure, a diamine residue derived from an aromatic diamine having no phenolic hydroxyl group and having an ionization potential (hereinafter simply abbreviated as "Ip") of 6.78 eV or more (hereinafter, such aromatic diamine is referred to as "aromatic diamine x1") (hereinafter, such polymer compound is referred to as "component (A)"); (B) a cationically polymerizable compound (hereinafter, referred to as "component (B)"); and (C) a photocationic polymerization initiator (hereinafter, referred to as "component (C)").

[0013] In the present invention, the terms "diamine residue" and "carboxylic acid residue" refer to partial structures other than the chemical bond portion in the structure of a polymer compound, where a diamine residue is a partial structure obtained by removing the amino group portion of a diamine as a monomer (including derivatives that function equivalently as a monomer), and a carboxylic acid residue is a partial structure obtained by removing the carboxyl group portion of a carboxylic acid as a monomer (including derivatives that function equivalently as a monomer). Therefore, in a polymer compound, a diamine residue is bonded to the nitrogen atom of an amino group that serves as a chemical bond portion, and a carboxylic acid residue is bonded to the carbonyl carbon of a carboxyl group that serves as a chemical bond.

[0014] Furthermore, in the present invention, "derived from an aromatic diamine" does not necessarily mean that the aromatic diamine is used as a monomer in the form of an aromatic diamine to obtain a polymer compound, but includes cases where a macromonomer or an oligomer is obtained using an aromatic diamine, and then the macromonomer or the oligomer is used to obtain a polymer compound. In other words, if the molecular structure contains an aromatic diamine residue, it can be said to be "derived from an aromatic diamine."

[0015] It is important that the photosensitive resin composition of the present invention contains the component (A).

[0016] Component (A) is understood to have the following two characteristics: Feature 1: At least one polymer compound selected from the group consisting of polyamide, polyimide, polyamideimide, and polybenzoxazole. Feature 2: The polymer compound has a diamine residue derived from aromatic diamine x1 as a partial structure.

[0017] Feature 1 refers to a polymer compound whose main chain has a chemical bond formed by a group selected from an amide group, an imide group (imide ring), and a benzoxazole group (benzoxazole ring), i.e., the repeating units are linked by these groups. Furthermore, component (A) may be a copolymer of two or more types selected from polyamide, polyimide, polyamideimide, and polybenzoxazole, and the copolymer may be a block copolymer, a random copolymer, or an alternating copolymer. Furthermore, within the scope of the present invention, for example, 5% or less of the total number of repeating units may be copolymerized with a monomer that forms a chemical bond other than a group selected from an amide group, an imide group (imide ring), and a benzoxazole group (benzoxazole ring), such as an ester bond-forming compound.

[0018] Furthermore, the component (A) may have a substituent on the diamine residue or carboxylic acid residue, and specific examples of the substituent include a carboxyl group, a carboxylic acid ester group, and a phenolic hydroxyl group. When the component (A) has a carboxyl group or a carboxylic acid ester group on the carbon adjacent to the carbon bonded to the carbonyl side of the amide group, an imide ring can be formed by a ring-closing reaction (polyimide precursor structure), and when the component (A) has a phenolic hydroxyl group on the carbon adjacent to the benzene ring carbon bonded to the nitrogen atom side of the amide group, a benzoxazole ring can be formed by a ring-closing reaction (polybenzoxazole precursor). These are preferred embodiments from the viewpoint of improving the heat resistance of the photosensitive resin composition.

[0019] Component (A) will now be described further with reference to specific examples.

[0020] Component (A) contains a carboxylic acid residue and a diamine residue. Examples of carboxylic acid residues include, but are not limited to, residues derived from dicarboxylic acids, tetracarboxylic acids, tricarboxylic acids, acid dianhydrides, and diacid chlorides. Component (A) may contain one or more types of carboxylic acid residues. The carboxylic acid residue contained in component (A) preferably contains an aromatic carboxylic acid residue. An aromatic carboxylic acid residue refers to a carboxylic acid residue derived from a carboxylic acid in which a carboxyl group is directly bonded to an aromatic ring. By containing an aromatic carboxylic acid residue, a cured product with excellent elongation can be obtained, even after a package reliability test.

[0021] Examples of aromatic tetracarboxylic acids that give aromatic carboxylic acid residues include 1,2,4,5-benzenetetracarboxylic acid (pyromellitic acid), 3,3',4,4'-biphenyltetracarboxylic acid, 2,3,3',4'-biphenyltetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 3,3',4,4'-benzophenonetetracarboxylic acid, and 2,2',3,3'-benzophenonetetracarboxylic acid. Nontetracarboxylic acid, bis(3,4-dicarboxyphenyl)methane, bis(2,3-dicarboxyphenyl)methane, 1,1-bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(2,3-dicarboxyphenyl)ethane, 2,2-bis(3,4-dicarboxyphenyl)propane, 2,2-bis(2,3-dicarboxyphenyl)propane, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane, 4,4'-(4,4'-isopropyl) 2,6-bis(3,4-dicarboxyphenylcarbonyloxy)naphthalene, 2,7-bis(3,4-dicarboxyphenylcarbonyloxy)naphthalene, 2,6-bis(3,4-dicarboxyphenylcarbonyloxy)diphthalic acid, 2,2-bis(2,3-dicarboxyphenyl)hexafluoropropane, bis(3,4-dicarboxyphenyl)sulfone, bis(3,4-dicarboxyphenyl)ether, 2,3,5,6-pyridinetetracarboxylic acid, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorene, 2,6-bis(3,4-dicarboxyphenylcarbonyloxy)naphthalene, 2,7-bis(3,4-dicarboxyphenylcarbonyloxy)naphthalene, 2,6-bis(3,4-dicarboxyphenylcarbonyloxy)naphthalene, 4,4'-(((perfluoropropane-2,2-diyl)bis(4,1-phenylene))bis(oxy))diphthalic acid, 4,4'-(((cyclodecane-1,1-diylbis(2-methyl-4,1-phenylene))bis(oxy))biscarbonyl))diphthalic acid, 4,4'-(((propane-2,2-diylbis(4,1-phenylene))bis(oxy))bis(carbonyl))diphthalic acid, 4,4'-(((2,2',3,3',5,5'-hexamethyl-[1,1'-biphenyl]-4,4'-diyl)bis(oxy))bis(carbonyl))diphthalic acid, 4,4'-((((9H-fluorene-9,9-diyl)bis(2-methyl-4,1-phenylene))bis(oxy))bis(carbonyl))diphthalic acid, 3,4,9,10-perylenetetracarboxylic acid, or N,N'-bis[5,5'-hexafluoropropane-2,2-diyl-bis(2-hydroxyphenyl)]bis(3,4-dicarboxybenzoic acid amide). Further examples include tetracarboxylic acid dianhydrides, tetracarboxylic acid dichlorides, and tetracarboxylic acid activated diesters thereof.

[0022] Examples of aromatic dicarboxylic acids that provide aromatic carboxylic acid residues include phthalic acid, isophthalic acid, terephthalic acid, 4,4'-dicarboxybiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-dicarboxybiphenyl, 4,4'-benzophenonedicarboxylic acid, 2,2-bis(4-carboxyphenyl)hexafluoropropane, 2,2-bis(3-carboxyphenyl)hexafluoropropane, and 4,4'-dicarboxydiphenyl ether. Also included are their dicarboxylic acid anhydrides, dicarboxylic acid chlorides, dicarboxylic acid activated esters, and diformyl compounds.

[0023] Examples of aromatic tricarboxylic acids that provide aromatic carboxylic acid residues include 1,2,4-benzenetricarboxylic acid, 1,3,5-benzenetricarboxylic acid, 2,4,5-benzophenonetricarboxylic acid, 2,4,4'-biphenyltricarboxylic acid, and 3,3',4'-tricarboxydiphenyl ether, as well as their tricarboxylic acid anhydrides, tricarboxylic acid chlorides, tricarboxylic acid activated esters, and diformyl monocarboxylic acids.

[0024] Examples of alicyclic tetracarboxylic acids that provide residues of alicyclic tetracarboxylic acids include bicyclo[2.2.2]octan-7-ene-2,3,5,6-tetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, and 2,3,4,5-tetrahydrofurantetracarboxylic acid, as well as tetracarboxylic acid dianhydrides, tetracarboxylic acid dichlorides, and tetracarboxylic acid activated diesters thereof.

[0025] Examples of aliphatic tetracarboxylic acids that provide the residue of aliphatic tetracarboxylic acid include butane-1,2,3,4-tetracarboxylic acid, and its tetracarboxylic acid dianhydride, tetracarboxylic acid dichloride, and tetracarboxylic acid activated diester.

[0026] Examples of alicyclic dicarboxylic acids that provide the residue of alicyclic dicarboxylic acid include 1,4-cyclohexanedicarboxylic acid and 1,2-cyclohexanedicarboxylic acid, as well as their dicarboxylic acid anhydrides, dicarboxylic acid chlorides, dicarboxylic acid activated esters, and diformyl compounds.

[0027] Examples of aliphatic dicarboxylic acids that provide the residue of aliphatic dicarboxylic acid include hexane-1,6-dicarboxylic acid, succinic acid, and dicarboxylic acid anhydrides, dicarboxylic acid chlorides, dicarboxylic acid activated esters, and diformyl compounds thereof.

[0028] Examples of alicyclic tricarboxylic acids that provide the residue of alicyclic tricarboxylic acid include 1,2,4-cyclohexanetricarboxylic acid and 1,3,5-cyclohexanetricarboxylic acid, as well as their tricarboxylic acid anhydrides, tricarboxylic acid chlorides, tricarboxylic acid activated esters, and diformyl monocarboxylic acids.

[0029] Examples of aliphatic tricarboxylic acids that provide the residue of aliphatic tricarboxylic acid include hexane-1,3,6-tricarboxylic acid and propane-1,2,3-tricarboxylic acid, as well as their tricarboxylic acid anhydrides, tricarboxylic acid chlorides, tricarboxylic acid activated esters, and diformyl monocarboxylic acids.

[0030] Component (A) has, as a partial structure, a diamine residue derived from an aromatic diamine (aromatic diamine x1) having no phenolic hydroxyl group and having an Ip of 6.78 eV or greater. The term "partial structure" refers to a portion present in the molecular structure (particularly the main chain structure). Ip is determined by a DFT method using Gaussian16W, with B3LYP as the functional and 6-311++G(d,p) as the basis functions constituting the molecular orbitals, and the structural parameters of each diamine optimized in the B3LYP / 6-311G(d) basis. The inventors have discovered that during pattern processing, when component (A) satisfies Feature 1 above and at the same time, the inclusion of a diamine residue derived from a specific aromatic diamine in the molecular chain of the polymer compound significantly affects the pattern processability of the photosensitive resin composition. When the polymer compound of component (A) contains a residue derived from aromatic diamine x1 in its molecular chain, the electron density of the nitrogen atoms of the imide and / or amide groups in component (A) is reduced, making it less likely to quench the acid generated from the photocationic polymerization initiator, and improving pattern processability. For the reasons mentioned above, this result shows a tendency not seen in pattern processing using photosensitive systems based on radical polymerization, and is presumed to be a result unique to photosensitive systems using cationic polymerization. The Ip of aromatic diamine x1 is preferably 7.05 eV or higher, more preferably 7.15 eV or higher, and even more preferably 7.40 eV or higher. The higher the Ip of aromatic diamine x1, the less likely acid quenching occurs, resulting in a photosensitive resin composition with excellent pattern processability. Furthermore, by using an aromatic diamine that does not have a phenolic hydroxyl group, compounding with component (B) can be prevented, reducing crosslink density, resulting in a cured product with excellent elongation. There is no particular upper limit to the Ip of the aromatic diamine x1, but it is preferably 10.00 eV or less from the viewpoint of the polymerizability of the polymer.

[0031] Specific examples of the aromatic diamine x1 include, but are not limited to, the following: The value in parentheses indicates the Ip (unit: eV) value of the aromatic diamine.

[0032]

[0033] The aromatic diamine x1 preferably has, in the diamine residue of a polymer compound, at least one bond selected from the group consisting of an ether bond, a sulfonyl bond, a ketone bond, and an ester bond. By having at least one of these bonds in the diamine residue, a cured product having excellent elongation even after a package reliability test can be obtained.

[0034] For the component (A), it is preferable to use both an aromatic diamine x1 having an Ip of 7.40 eV or more (for convenience, referred to as "aromatic diamine x1-1") and an aromatic diamine x1 having an Ip of 6.78 eV or more but less than 7.40 eV (for convenience, referred to as "aromatic diamine x1-2"). When an aromatic diamine x1 having an Ip of 7.40 eV or more is used, pattern processability is further improved. Furthermore, when an aromatic diamine x1 having an Ip of 6.78 eV or more, preferably 7.05 eV or more, more preferably 7.15 eV or more, and less than 7.40 eV is used, the elongation of the cured product is further improved. Therefore, by using an aromatic diamine x1 having such an Ip, a cured product with excellent elongation can be obtained without impairing pattern processability.

[0035] Furthermore, from the viewpoint of achieving excellent pattern processability, excellent elongation of the cured product, and excellent elongation of the cured product even after a package reliability test, when the total amount of diamine residues in the component (A) is taken as 100 mol%, it is preferable that the content of diamine residues derived from aromatic diamine x1-1 is 10 to 55 mol%, more preferably 10 to 30 mol%, and the content of diamine residues derived from aromatic diamine x1-2 is 45 to 90 mol%, more preferably 70 to 90 mol%.

[0036] Furthermore, from the viewpoint of excellent pattern processability, when the total amount of diamine residues in the component (A) is taken as 100 mol %, the content of diamine residues derived from the aromatic diamine x1 is preferably 55 to 100 mol %, and more preferably 75 to 100 mol %.

[0037] The component (A) may contain a diamine residue having a siloxane skeleton in its molecular structure.

[0038] Examples of diamines that provide diamine residues having a siloxane skeleton include bis(3-aminopropyl)tetramethyldisiloxane and bis(p-aminophenyl)octamethylpentasiloxane. However, it is preferable to use a diamine having a siloxane skeleton represented by formula (2).

[0039]

[0040] (p represents an integer of 1 to 40. R １ and R ６ R each independently represents an alkylene group having 1 to 15 carbon atoms. ２ ~R ５ each independently represents an alkyl group having 1 to 15 carbon atoms or an aryl group having 6 to 10 carbon atoms. * represents a bonding site.) In formula (2), p is preferably 1 to 10. Having p be 10 or less is preferred in that it increases compatibility with other monomers and solvents used to obtain component (A) during polymerization.

[0041] Furthermore, as long as the component (A) contains a diamine residue derived from the aromatic diamine x1, it may contain a diamine residue derived from any diamine other than the aromatic diamine x1. Examples of diamines other than the aromatic diamine x1 include residues of aromatic diamines having an Ip of less than 6.78 eV, aromatic diamines having a phenolic hydroxyl group, alicyclic diamines, aliphatic diamines, and derivatives thereof.

[0042] Examples of aromatic diamines having an Ip of less than 6.78 eV and aromatic diamines having a phenolic hydroxyl group include 2,3,5,6-tetramethyl-1,4-phenylenediamine, 2,3-diaminobiphenyl, 2,2'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethyl-biphenyl-4,4'-diamine, 2,7-diaminofluorene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-diaminobiphenyl, bis(4-aminophenoxy)biphenyl, bis(3-amino-4-hydroxyphenyl) bis(3-amino-4-hydroxyphenyl)methane, 1,1-bis(3-amino-4-hydroxyphenyl)ethane, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)sulfone, and bis(3-amino-4-hydroxyphenyl)ether. Also included are diisocyanate compounds thereof or trimethylsilylated diamines, but are not limited to these.

[0043] Examples of alicyclic diamines include compounds in which the aromatic rings of the above-mentioned aromatic diamines are substituted with aliphatic hydrocarbon rings, 1,2-cyclohexanediamine, 1,4-cyclohexanediamine, bis(4-aminocyclohexyl)methane, 3,6-dihydroxy-1,2-cyclohexanediamine, 2,5-dihydroxy-1,4-cyclohexanediamine, bis(3-hydroxy-4-aminocyclohexyl)methane, and diisocyanate compounds or trimethylsilylated diamines thereof, but are not limited to these.

[0044] Examples of aliphatic diamines include, but are not limited to, 1,6-hexamethylenediamine or 2,5-dihydroxy-1,6-hexamethylenediamine, as well as diisocyanate compounds thereof or trimethylsilylated diamines thereof.

[0045] Component (A) may also contain a triamine residue in its molecular structure. Examples of triamines that provide the triamine residue include aromatic triamines, alicyclic triamines, and aliphatic triamines, as well as derivatives thereof.

[0046] Examples of aromatic triamines include, but are not limited to, 1,3,5-tris(4-aminophenoxy)benzene and 2,4,6-triaminopyrimidine, as well as triisocyanate compounds thereof or trimethylsilylated triamines.

[0047] The component (A) may be a polymer compound whose molecular ends are blocked with a known terminal blocking material such as a monocarboxylic acid, an acid anhydride, a monoacid chloride, a monoamine, or a monoisocyanate. The terminal blocking material may be used alone or in combination of two or more types.

[0048] From the viewpoint of the viscosity and pattern processability of the resulting resin composition, the weight average molecular weight of component (A) is preferably from 1,000 to 200,000, more preferably from 3,000 to 100,000, and even more preferably from 5,000 to 50,000. The weight average molecular weight of component (A) in the present invention is measured by gel permeation chromatography (GPC) using N-methylpyrrolidone as a developing solvent and calculated in terms of polystyrene.

[0049] The amounts of carboxylic acid residues and diamine residues contained in component (A) can be determined, for example, by the following method. Specifically, the amount can be determined by dissolving component (A) in an acidic solution and analyzing the solution using gas chromatography (GC) or nuclear magnetic resonance (NMR). Alternatively, the amount can be determined by directly analyzing the photosensitive resin composition or component (A) using NMR or the like. Furthermore, when a photosensitive resin composition is prepared using a polymerization solution of component (A) as is, the ratio of residues such as carboxylic acid residues and diamine residues contained in component (A) corresponds to the monomer charge ratio during polymerization of component (A), and therefore can also be determined from the monomer charge ratio during polymerization of component (A).

[0050] In the present invention, component (A) can be synthesized by a known method. After polymerizing component (A) by a known method, it is preferable to add it to a large amount of water or a mixture of methanol and water, precipitate it, filter it, dry it, and isolate it. The drying temperature is preferably 40 to 100°C, more preferably 50 to 80°C. This procedure can remove unreacted monomers and oligomer components such as dimers and trimers, and is preferable in that it improves the heat resistance and chemical resistance of the cured product. Next, the cationically polymerizable compound (component (B)) will be described.

[0051] The cationically polymerizable compound (component (B)) refers to a compound containing a functional group that crosslinks by cationic polymerization, and specific examples thereof include cyclic ether compounds such as epoxy compounds and oxetane compounds, ethylenically unsaturated compounds such as vinyl ethers and styrenes, episulfide compounds, bicycloorthoesters, spiroorthocarbonates, and spiroorthoesters.

[0052] As the epoxy compound, known compounds can be used, and examples thereof include aromatic epoxy compounds, alicyclic epoxy compounds, and aliphatic epoxy compounds.

[0053] Examples of aromatic epoxy compounds include glycidyl ethers of mono- or polyhydric phenols having at least one aromatic ring (phenol, bisphenol A, phenol novolak, and alkylene oxide adducts thereof).

[0054] Examples of alicyclic epoxy compounds include compounds obtained by epoxidizing a compound having at least one cyclohexene or cyclopentene ring with an oxidizing agent (e.g., 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate).

[0055] Examples of the aliphatic epoxy compound include polyglycidyl ethers of aliphatic polyhydric alcohols or their alkylene oxide adducts (1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, etc.), polyglycidyl esters of aliphatic polybasic acids (diglycidyl tetrahydrophthalate, etc.), and epoxidized products of long-chain unsaturated compounds (epoxidized soybean oil, epoxidized polybutadiene, etc.).

[0056] Among these, polyfunctional epoxy compounds that are liquid at room temperature (20°C) are preferred, and the polyfunctional epoxy compounds preferably have an epoxy equivalent of 80 g / eq. or more and 500 g / eq. or less. The polyfunctional epoxy compounds being liquid at room temperature are preferred in that they improve compatibility with component (A) and enable fine pattern processability. On the other hand, the polyfunctional epoxy compounds having an epoxy equivalent of 80 g / eq. or more and 500 g / eq. or less are preferred in that they improve the heat resistance and chemical resistance of the cured film.

[0057] It is particularly preferred that all or part of component (B) is a compound represented by formula (1). Use of a compound represented by formula (1) can further increase the elongation of the cured product without impairing pattern processability.

[0058]

[0059] (A １ represents an alkylene group having 1 to 20 carbon atoms or a divalent hydrocarbon group having 3 to 20 carbon atoms and an aliphatic hydrocarbon ring; B １ , B ２each independently represents an ether bond or an ester bond.) Examples of the alkylene group having 1 to 20 carbon atoms include a methylene group, an ethylene group, a propylene group, an isopropylene group, a butylene group, a sec-butylene group, a tert-butylene group, an isobutylene group, a pentylene group, an isopentylene group, a tert-pentylene group, a hexylene group, a 2-hexylene group, a 3-hexylene group, a heptylene group, a 2-heptylene group, a 3-heptylene group, an isoheptylene group, a tert-heptylene group, an octylene group, an isooctylene group, a tert-octylene group, a 2-ethylhexylene group, a nonylene group, an isononylene group, a decylene group, an n-undecylene group, a 1-methyldecylene group, Examples of the alkyl group include a 4-dodecylene group, a 4-ethyloctylene group, a 1,3,5,7-tetramethyloctylene group, a tridecylene group, a 1-hexylheptylene group, an n-tetradecylene group, an n-pentadecylene group, and an n-hexadecylene group.

[0060] Examples of the divalent hydrocarbon group having 3 to 20 carbon atoms and an aliphatic hydrocarbon ring include a cycloalkylene group and a group formed by combining a cycloalkylene group with an alkylene group. Examples of the cycloalkylene group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, and a cyclohexylene group. In addition, some of the hydrogen atoms in the cycloalkylene group may be substituted with alkyl groups.

[0061] Examples of the compound represented by formula (1) include ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, diglycidyl-1,2-cyclohexanedicarboxylate, and 1,2-cyclohexanedicarboxylate diglycidyl.

[0062] In addition, from the viewpoint of excellent pattern processability, in formula (1), B １ , B ２ is more preferably an ether bond.

[0063] The content of the compound represented by formula (1) is preferably 10 parts by mass or more per 100 parts by mass of the component (A) from the viewpoint of obtaining excellent elongation, and is preferably 70 parts by mass or less per 100 parts by mass of the component (A) from the viewpoint of excellent pattern processability.

[0064] As the oxetane compound, known compounds can be used, such as 3-ethyl-3-hydroxymethyloxetane, 2-ethylhexyl(3-ethyl-3-oxetanylmethyl)ether, 2-hydroxyethyl(3-ethyl-3-oxetanylmethyl)ether, 2-hydroxypropyl(3-ethyl-3-oxetanylmethyl)ether, 3-ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane, 1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene, 4,4'-bis[(3-ethyloxetan-3-yl)methoxy]biphenyl, oxetanylsilsesquioxetane, and phenol novolac oxetane. Here, an epoxy compound having an oxetanyl group corresponds to the oxetane compound. Among these, an oxetane compound containing two or more oxetanyl groups in the molecule is preferred, and the number of oxetanyl groups in one molecule is more preferably from 2 to 6. The oxetane compound containing two or more oxetanyl groups is preferred in terms of improving curability, and the oxetane compound containing six or less oxetanyl groups is preferred in terms of suppressing cracks that occur during pattern processing.

[0065] As the ethylenically unsaturated compound, known cationically polymerizable monomers can be used, including aliphatic monovinyl ethers, aromatic monovinyl ethers, polyfunctional vinyl ethers, styrene, and cationically polymerizable nitrogen-containing monomers.

[0066] Aliphatic monovinyl ethers include methyl vinyl ether, ethyl vinyl ether, butyl vinyl ether, and cyclohexyl vinyl ether.

[0067] Examples of aromatic monovinyl ethers include 2-phenoxyethyl vinyl ether, phenyl vinyl ether, and p-methoxyphenyl vinyl ether.

[0068] Examples of polyfunctional vinyl ethers include butanediol-1,4-divinyl ether and triethylene glycol divinyl ether.

[0069] Examples of styrenes include styrene, α-methylstyrene, p-methoxystyrene, and p-tert-butoxystyrene.

[0070] Examples of the cationically polymerizable nitrogen-containing monomer include N-vinylcarbazole and N-vinylpyrrolidone.

[0071] As the episulfide compound, known compounds can be used, such as 2,2-bis[4-(2,3-epithiopropoxy)phenyl]propane and 2,2-bis[4-(2,3-epithiopropoxy)cyclohexyl]propane.

[0072] Bicyclo orthoesters include 1-phenyl-4-ethyl-2,6,7-trioxabicyclo[2.2.2]octane and 1-ethyl-4-hydroxymethyl-2,6,7-trioxabicyclo-[2.2.2]octane.

[0073] Examples of spiro orthocarbonates include 1,5,7,11-tetraoxaspiro[5.5]undecane and 3,9-dibenzyl-1,5,7,11-tetraoxaspiro[5.5]undecane.

[0074] Spiro orthoesters include 1,4,6-trioxaspiro[4.4]nonane, 2-methyl-1,4,6-trioxaspiro[4.4]nonane, and 1,4,6-trioxaspiro[4.5]decane.

[0075] The photosensitive resin composition of the present invention preferably uses an oxetane compound as component (B). By using an oxetane compound as component (B), the propagation reaction of cationic polymerization is promoted, thereby exhibiting good sensitivity and resolution, and side reactions are less likely to occur. The molecular weight of the cationic polymer is increased, resulting in excellent elongation of the cured product.

[0076] The oxetane compound is more preferably an oxetane compound represented by formula (3).

[0077]

[0078] (g and h each independently represent an integer of 0 to 6, R ７ and R ８ each independently represents a monovalent organic group having 1 to 5 carbon atoms.) In particular, an oxetane compound in which g in formula (3) is 1 to 6 exhibits good elongation when the photosensitive resin composition of the present invention is formed into a cured film.

[0079] In the formula (3), examples of the "organic group" include an alkyl group having 1 to 5 carbon atoms and an alkenyl group having 1 to 5 carbon atoms.

[0080] Examples of such oxetane compounds include OXT-121 (trade name, manufactured by Toagosei Co., Ltd.) and OXBP (trade name, manufactured by UBE Co., Ltd.).

[0081] As the epoxy compound, it is more preferable to use an epoxy compound represented by formula (5).

[0082]

[0083] (j, k, and l each independently represent an integer of 1 to 10.) Such an epoxy compound as component (B) has high compatibility with component (A), and can improve sensitivity. Examples of such epoxy compounds include TEPIC-FL and TEPIC-VL (all trade names, manufactured by Nissan Chemical Industries, Ltd.). In relation to formula (5), for TEPIC-FL, j = k = l = 4, and for TEPIC-VL, j = k = l = 1.

[0084] In the photosensitive resin composition of the present invention, when the content of the component (A) is taken as 100 parts by mass, the content of the component (B) is preferably 80 parts by mass or more and 150 parts by mass or less. By setting the content in this range, the compatibility between the components (A) and (B) is improved, and excellent pattern processability can be obtained. When the content of the component (A) is taken as 100 parts by mass, the lower limit of the content of the component (B) is more preferably 100 parts by weight or more, and from the viewpoint of the strength of the cured product, the upper limit is more preferably 130 parts by weight or less.

[0085] Next, the cationic photopolymerization initiator (component (C)) will be described.

[0086] The component (C) is a compound that generates an acid when exposed to light, thereby causing cationic polymerization.

[0087] Although known compounds can be used as component (C), from the viewpoints of cationic curability and copper corrosion resistance, component (C) preferably contains a sulfonium salt containing at least one counter anion selected from the group consisting of borate ions, phosphate ions, and gallate ions. Here, borate ions are complex ions having boron as the central atom, phosphate ions are complex ions having phosphorus as the central atom, and gallate ions are complex ions having gallium as the central atom.

[0088] Examples of the cation that forms the sulfonium salt include triphenylsulfonium cation, tri-p-tolyl sulfonium cation, tris(4-methoxyphenyl)sulfonium cation, 1-naphthyldiphenylsulfonium cation, 2-naphthyldiphenylsulfonium cation, tris(4-fluorophenyl)sulfonium cation, tri-1-naphthylsulfonium cation, tri-2-naphthylsulfonium cation, tris(4-hydroxyphenyl)sulfonium cation, 4-(phenylthio)phenyldiphenylsulfonium cation, 4-(p-tolylthio)phenyldi-p-tolyl sulfonium cation, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium cation, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium cation, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium cation, 4-(phenylthio)phenyldi-p-tolyl sulfonium cation, [4-(4-biphenylylthio)phenyl]-4-biphenylylphenyl sulfonium cation, [4-(2-thiphenyl) oxanthonylthio)phenyl]diphenylsulfonium cation, bis[4-(diphenylsulfonio)phenyl]sulfide cation, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide cation, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide cation, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide cation, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide cation, 4-(4-benzoyl-2 4-(4-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium cation, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium cation, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium cation, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium cation, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium cation, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium cation,10-dihydroanthracen-2-yldiphenylsulfonium cation, 2-[(di-p-tolyl)sulfonio]thioxanthone cation, 2-[(diphenyl)sulfonio]thioxanthone cation, 4-(9-oxo-9H-thioxanthen-2-yl)thiophenyl-9-oxo-9H-thioxanthen-2-ylphenylsulfonium cation, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium cation, 4-[4-(4-te 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium cation, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium cation, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium cation, 5-(4-methoxyphenyl)thiaanthrenenium cation, 5-phenylthiaanthrenenium cation, 5-tolylthiaanthrenenium cation, 5-(4-ethoxyphenyl)thiaanthrenenium cation, 5-(2,4,triarylsulfonium cations such as diphenylphenacylsulfonium cation, diphenyl-4-nitrophenacylsulfonium cation, diphenylbenzylsulfonium cation, diphenylmethylsulfonium; phenylmethylbenzylsulfonium cation, 4-hydroxyphenylmethylbenzylsulfonium cation, 4-methoxyphenylmethylbenzylsulfonium cation, 4-acetocarbonyloxyphenylmethylbenzylsulfonium cation, 4-hydroxyphenyl(2-naphthylmethyl)methylsulfonium cation, 2-naphthylmethylbenzylsulfonium cation, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium monoarylsulfonium cations such as phenylmethylphenacylsulfonium cation, 4-hydroxyphenylmethylphenacylsulfonium cation, 4-methoxyphenylmethylphenacylsulfonium cation, 4-acetocarbonyloxyphenylmethylphenacylsulfonium cation, 2-naphthylmethylphenacylsulfonium cation, 2-naphthyloctadecylphenacylsulfonium cation, and 9-anthracenylmethylphenacylsulfonium; dimethylphenacylsulfonium cation, phenacyltetrahydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium cation, and octadecylmethylphenacylsulfonium cation, but are not limited to these.

[0089] Examples of borate ions include, but are not limited to, pentafluorophenylborate ion, trifluorophenylborate, tetrafluorophenylborate ion, trifluoromethylphenylborate ion, bis(trifluoromethyl)phenylborate ion, pentafluoroethylphenylborate ion, bis(pentafluoroethyl)phenylborate ion, fluoro-bis(trifluoromethyl)phenylborate ion, fluoro-pentafluoroethylphenylborate ion, and fluoro-bis(pentafluoroethyl)phenylborate ion.

[0090] Examples of phosphate ions include, but are not limited to, hexafluorophosphate ion, tris(pentafluoroethyl)trifluorophosphate ion, and the like.

[0091] Examples of gallate ions include, but are not limited to, tetrakis(pentafluorophenyl)gallate ion, tetrakis(3,5-bis(trifluoromethyl)phenyl)gallate ion, and the like.

[0092] From the viewpoint of sufficient cationic polymerization of the component (B) and obtaining a good pattern shape, the content of the component (C) in the sensitive resin composition of the present invention is preferably 0.3 parts by mass or more and 10 parts by mass or less, and more preferably 0.5 parts by mass or more and 8 parts by mass or less, per 100 parts by mass of the component (B).

[0093] The photosensitive resin composition of the present invention may contain a sensitizer. The sensitizer is a compound that can absorb light, donate the absorbed light energy to component (C), and enhance acid generation. The sensitizer can also absorb light at the irradiation wavelength during pattern processing, thereby reducing the transmittance of the photosensitive resin composition film formed from the photosensitive resin composition at the irradiation wavelength. Therefore, the transmittance of the negative photosensitive resin composition film at the irradiation wavelength can be arbitrarily controlled by adjusting the content of the sensitizer in the photosensitive resin composition.

[0094] The photosensitive resin composition of the present invention may contain a silane compound. By including a silane compound, the adhesion between the cured product and the substrate is improved. The content of the silane compound is preferably 0.01 to 10 parts by mass, relative to 100 parts by mass of the mass of component (A) contained in the photosensitive resin composition. Here, the silane compound having a cationically polymerizable functional group is not the silane compound described above, but component (B). Examples of silane compounds containing a cationically polymerizable group include KBM-303 and KBM-403 (both product names, manufactured by Shin-Etsu Chemical Co., Ltd.). Adhesion improvers having a triazine ring are also preferred in terms of improving the adhesion between the cured product and the substrate, and examples thereof include KBM-9659 (product name, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0095] The cured product of the present invention is a cured product obtained by curing the photosensitive resin composition of the present invention. The cured product of the present invention may be in any form as long as the photosensitive resin composition is cured by light or heat.

[0096] Examples of the method for curing with light or heat include known methods such as a method of curing by exposure to 50 mJ to 3,000 mJ of 365 nm i-line, 405 nm h-line, or 436 nm g-line from a high-pressure mercury lamp, and a method of curing by heat treatment at 150°C to 500°C for 5 minutes to 5 hours.

[0097] A method for producing a cured product of the present invention will be described. The method for producing a cured product is a method for producing a cured product using the photosensitive resin composition of the present invention, and includes the steps of applying the photosensitive resin composition on a substrate and drying it to form a photosensitive resin composition film, exposing the photosensitive resin composition film to light, developing the exposed photosensitive resin composition film, and curing the developed photosensitive resin composition film.

[0098] The process of applying the photosensitive resin composition to a substrate and drying to form a photosensitive resin composition film on the substrate includes, but is not limited to, applying the photosensitive resin composition to a substrate using a spin coater, spray coater, screen coater, blade coater, die coater, calendar coater, meniscus coater, bar coater, roll coater, comma roll coater, gravure coater, slit die coater, etc., and drying at a temperature in the range of 50 ° C. to 150 ° C. for 1 minute to several hours to form a photosensitive resin composition film. Specific examples of the substrate include, but are not limited to, silicon wafers, ceramics, gallium arsenide, organic circuit boards, inorganic circuit boards, and substrates on which circuit components are arranged.

[0099] Examples of the step of exposing the photosensitive resin composition film include, but are not limited to, a step of exposing the film to 365 nm i-line, 405 nm h-line, and 436 nm g-line from a high-pressure mercury lamp at 50 mJ or more and 3000 mJ or less through a mask having a desired pattern. The photosensitive resin composition film exposed by the above step may be subjected to post-exposure baking. From the viewpoints of curability and adhesion to the substrate, the post-exposure baking is preferably performed at 50°C or more, and from the viewpoint of resolution, it is preferably performed at 150°C or less. Exposure induces a polymerization reaction of component (B) with component (C).

[0100] Specific examples of the process for developing the photosensitive resin composition film after exposure include, but are not limited to, spraying a developer onto the photosensitive resin composition film surface, puddling the developer on the film surface, immersing the film in the developer, or immersing the film in the developer and applying ultrasonic waves. The development conditions, such as the development time and the temperature of the developer, may be any conditions that allow the exposed area to be removed and a pattern to be formed. The developer used for development is preferably a good solvent for the photosensitive resin composition, or a mixture of the good solvent and a poor solvent. For example, preferred good solvents include N-methylpyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, and propylene glycol methyl ether acetate. Preferred poor solvents include toluene, xylene, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, and water. 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 depending on the solubility of the polymer in the photosensitive resin composition. Furthermore, two or more kinds of each solvent can be used in combination.

[0101] Furthermore, when the photosensitive resin composition is soluble in an alkaline aqueous solution, development may be performed using an alkaline aqueous solution. The developer used for development dissolves and removes polymers soluble in alkaline aqueous solutions, and is typically an alkaline aqueous solution containing an alkaline compound dissolved therein. Examples of alkaline compounds include tetramethylammonium hydroxide, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, and potassium carbonate. In some cases, these alkaline aqueous solutions may contain, alone or in combination, polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, and γ-butyrolactone; alcohols such as methanol, ethanol, and isopropanol; esters such as ethyl lactate and propylene glycol monomethyl ether acetate; and ketones such as cyclopentanone, cyclohexanone, and isobutyl ketone.

[0102] After development, it is preferable to perform a rinse treatment with an organic solvent or water. When an organic solvent is used, in addition to the above-mentioned developer, examples of the solvent include ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, and isopropyl alcohol. When water is used, alcohols such as ethanol and isopropyl alcohol, and esters such as ethyl lactate and propylene glycol monomethyl ether acetate may also be added to the water for rinsing.

[0103] The process of curing the photosensitive resin composition film after development to form a cured product can be, for example, a process of heat-treating the film at a temperature in the range of 150°C to 500°C for 5 minutes to 5 hours to form a cured product. The heat treatment can be performed by selecting a temperature and gradually increasing the temperature, or by selecting a temperature range and continuously increasing the temperature. An example of the former is a method of performing heat treatment at 130°C and 200°C for 30 minutes each. An example of the latter is a method of linearly increasing the temperature from room temperature to 400°C over 2 hours. The cured product formed from the photosensitive resin composition of the present invention can be used as an insulating film or protective film that constitutes an electronic component.

[0104] The electronic component of the present invention is an electronic component comprising the cured product of the present invention.

[0105] Here, examples of electronic components include active components having semiconductors such as transistors and diodes, and passive components such as resistors, capacitors, inductors, etc. Furthermore, a device made up of electronic components using semiconductors is called a semiconductor device.

[0106] Specific examples of the cured product used in electronic components include, but are not limited to, semiconductor passivation films, surface protective films for semiconductor elements, TFTs (Thin Film Transistors), and other interlayer insulating films such as interlayer insulating films between rewirings in multilayer wiring for high-density packaging of 2 to 10 layers, insulating films and protective films for touch panel displays, and insulating layers for organic electroluminescent devices. The semiconductor element is an element containing a semiconductor, and examples thereof include integrated circuits (ICs), memories, and the like.

[0107] Among the electronic components of the present invention, examples of semiconductor devices include chip-first fan-out wafer-level packages and chip-first fan-out panel-level packages. Chip-first fan-out wafer-level packages and chip-first fan-out panel-level packages are semiconductor packages in which an extension section is provided around a semiconductor chip using an encapsulating resin such as epoxy resin, rewiring is performed from electrodes on the semiconductor chip to the extension section, and solder balls are also mounted on the extension section to ensure the required number of terminals. In chip-first fan-out wafer-level packages and chip-first fan-out panel-level packages, wiring is installed so as to straddle the boundary formed by the main surface of the semiconductor chip and the main surface of the encapsulating resin, and a cured product is arranged as an insulating film between the wiring.

[0108] The electronic component of the present invention preferably comprises the cured product of the present invention disposed as an insulating film between wirings, i.e., the electronic component of the present invention preferably takes the form of a chip-first fan-out wafer-level package or a chip-first fan-out panel-level package.

[0109] As an example of the method for manufacturing electronic components of the present invention, a semiconductor device is manufactured using a redistribution layer (RDL) first process. A barrier metal such as Ti is formed on a support substrate such as a glass substrate or silicon wafer by sputtering, and a Cu seed (seed layer) is then formed on top of that by sputtering. After that, Cu electrode pads are formed by a process that includes resist processing, electrolytic plating, resist stripping, and seed layer etching (the process from seed layer formation to etching is called the semi-additive process (SAP)). Next, the photosensitive resin composition of the present invention is applied to the entire surface of the support substrate on which the electrode pads have been formed, and dried to form a photosensitive resin film. Lines and spaces, square, or hole patterns are formed in the resulting photosensitive resin film as needed. A heat treatment is then performed to form a cured layer. This layer becomes an insulating film. Next, metal wiring (redistribution wiring) made of Cu is formed again by SAP. Subsequently, the insulating film and SAP processes are repeated to form a multilayer wiring structure. Next, the photosensitive resin composition of the present invention is again applied and patterned, followed by heat treatment and curing to form an insulating film. Then, in the openings of the insulating film, Cu posts are formed on the metal wiring using SAP. The pitch of the Cu posts and the pitch of the conductive portions of the semiconductor chip are made equal. That is, the pitch of the conductive portions of the semiconductor chip is finer than the pitch of the electrode pads, and each rewiring layer constituting the multilayer wiring structure gradually becomes finer in pitch from the electrode pads to the Cu posts, thereby multiplying the wiring. In the multilayer wiring structure, the thickness of adjacent insulating films also becomes the same or thinner as they approach the semiconductor chip. Next, the semiconductor chip is connected to the Cu posts via solder bumps. This electrically connects the electrode pads and the semiconductor chip via the metal wiring and solder bumps. The semiconductor chip is then encapsulated with an encapsulating resin to form a semiconductor package, and the support substrate and the rewiring layer are peeled off to separate the semiconductor package. In this way, a semiconductor device having a multilayer wiring structure using the RDL first process can be obtained.

[0110] The present invention will be described below with reference to examples, but the present invention should not be construed as being limited to these examples.

[0111] [Evaluation Methods] (1) Weight-average molecular weight, dispersity The weight-average molecular weight (Mw) was confirmed using a GPC (gel permeation chromatography) apparatus, Waters 2690-996 (manufactured by Nippon Waters Co., Ltd.). Measurement was performed using N-methyl-2-pyrrolidone (hereinafter also referred to as NMP) as the developing solvent, and the weight-average molecular weight (Mw) and dispersity (PDI; PDI = Mw / Mn) were calculated in terms of polystyrene.

[0112] (2)-1 Pattern Processability The varnish was spin-coated onto a silicon wafer using a spin coater (1H-360S manufactured by Mikasa Co., Ltd.), and then pre-baked for 3 minutes at 120°C using a hot plate (SCW-636 manufactured by Dainippon Screen Mfg. Co., Ltd.) to produce a pre-baked film with a film thickness of 11 μm. The obtained pre-baked film was irradiated with 150 mJ / cm2 of light using a parallel light mask aligner (PLA-501F manufactured by Canon Inc.) with an ultra-high pressure mercury lamp as a light source (a mixed line of g-line, h-line, and i-line) through a mask having a pattern with a line width of 10 μm. ２ , 300 mJ / cm ２ , 500 mJ / cm ２ , 700 mJ / cm ２ , 1000mJ / cm ２ , 1300mJ / cm ２ , 1600mJ / cm ２ and 2000 mJ / cm ２ The exposure was performed at each exposure dose, which was calculated by measuring the illuminance of i-line (365 nm).

[0113] The exposed prebaked film was then baked at 120°C for 3 minutes, and then developed by immersion in propylene glycol monomethyl ether acetate (PGMEA) as a developer. It was then rinsed by immersion in isopropyl alcohol (IPA) for 40 seconds. The immersion time in the developer was determined in advance as (BP) seconds, the time until the unexposed areas dissolved and the substrate was exposed, and was set to (BP x 1.5) seconds. However, if the unexposed areas were not exposed even after immersion in the developer for 200 seconds, it was determined that pattern processing was not possible, and further evaluation was not performed. Furthermore, samples in which the pattern in the exposed areas dissolved after development for (BP x 1.5) seconds were not further evaluated.

[0114] The evaluation was based on the minimum exposure dose at which a pattern with a line width of 10 μm was opened after development and rinsing. The minimum exposure dose at which a pattern with a line width of 10 μm was opened was taken as the sensitivity and evaluated on a five-level scale from A to E as shown in Table 1 below.

[0115] The film thickness was measured using a Lambda Ace STM-602 manufactured by Dai-Nippon Screen Mfg. Co., Ltd., with the refractive index of the object being measured set to 1.629. Film thicknesses described below were also determined in the same manner.

[0116]

[0117] (2)-2 PEB Temperature Dependence The varnish was spin-coated onto a silicon wafer using a spin coater (1H-360S, manufactured by Mikasa Co., Ltd.), and then pre-baked for 3 minutes at 120°C using a hot plate (SCW-636, manufactured by Dainippon Screen Mfg. Co., Ltd.) to produce a pre-baked film with a film thickness of 11 μm. The obtained pre-baked film was exposed to light using a parallel light mask aligner (PLA-501F, manufactured by Canon Inc.) with an ultra-high pressure mercury lamp as a light source (a mixed line of g-line, h-line, and i-line) through a mask having a line width of 10 μm, at an exposure dose similar to that obtained in (2)-1. The exposure dose was calculated by measuring the illuminance of i-line (365 nm).

[0118] The exposed pre-baked film was then baked at 110°C for 3 minutes (Sample 1) and at 130°C for 3 minutes (Sample 2), and each sample was developed by immersion in propylene glycol monomethyl ether acetate (PGMEA) as a developer, and then rinsed by immersion in isopropyl alcohol (IPA) for 40 seconds. The immersion time in the developer was the same as the evaluation conditions in (2)-1.

[0119] The evaluation was carried out by checking the opening dimensions (line width, unit: μm) of the pattern after development and rinsing, and calculating the PEB temperature dependency using the following formula.

[0120] PEB temperature line width change (μm)=opening dimension in sample 2−opening dimension in sample 1. PEB temperature line width change of less than 1 μm was evaluated as A, 1 μm or more as B, and pattern processing unacceptable as C.

[0121] (3) Evaluation of Cured Product Properties (3)-1 Elongation at Break The varnish was applied to an 8-inch silicon wafer by spin coating using a coater / developer MARK-7 (manufactured by Tokyo Electron Limited) so that the film thickness after pre-baking at 120°C for 3 minutes would be 11 μm, and the wafer was then pre-baked. The wafer was then heated to 200°C at a rate of 3.5°C / min in an inert oven CLH-21CD-S (manufactured by Koyo Thermo Systems Co., Ltd.) at an oxygen concentration of 20 volume ppm or less, and heat-treated at 200°C for 1 hour. When the temperature reached 50°C or less, the wafer was removed and immersed in 45% by mass hydrofluoric acid for 1 minute to peel off the cured film from the wafer. The film was cut into strips 1.5 cm wide and 5 cm long, and stretched at a tension rate of 5 mm / min using a Tensilon RTM-100 (manufactured by Orientec Co., Ltd.) at room temperature of 23.0 ° C and humidity of 45.0% RH at a tension rate of 5 mm / min to measure the elongation at break. Ten strips were prepared for each specimen, and the arithmetic average of the five highest elongations at break was calculated (the calculated elongation at break is conveniently referred to as "elongation 1"). Elongation values ​​of 90% or more were rated A, 80% or more but less than 90% were rated B+, 60% or more but less than 80% were rated B, 30% or more but less than 60% were rated C, and less than 30% were rated D. The higher the elongation at break value, the better the elongation.

[0122] (3)-2 Elongation at Break and Rate of Change in Elongation at Break After Reliability Test (High Temperature Storage Test (HTS)) The varnish was applied to an 8-inch silicon wafer by spin coating using a coater / developer MARK-7 (manufactured by Tokyo Electron Limited) so that the film thickness after pre-baking at 120°C for 3 minutes would be 11 μm, and the wafer was then pre-baked. Using an inert oven CLH-21CD-S (manufactured by Koyo Thermo Systems Co., Ltd.), the wafer was heated to 200°C at a rate of 3.5°C / min at an oxygen concentration of 20 ppm by volume or less, and heat-treated at 200°C for 1 hour. When the temperature reached 50°C or less, the wafer with the cured film was removed, and the wafer with the cured film was placed in an oven (Clean Oven DE42, manufactured by Yamato Scientific Co., Ltd.), and heat-treated at 175°C for 200 hours under atmospheric pressure. After the heat treatment, the wafer was removed and immersed in 45% by mass hydrofluoric acid for 1 minute to remove the cured film from the wafer. The film was cut into strips 1.5 cm wide and 5 cm long, and the elongation at break was measured using a Tensilon RTM-100 (manufactured by Orientec Co., Ltd.) at room temperature of 23.0°C and humidity of 45.0% RH at a tensile speed of 5 mm / min. Ten strips were prepared for each specimen, and the arithmetic mean value of the five highest elongations at break was calculated from the measurement results, and this was designated as the elongation at break (%) after HTS (for convenience, referred to as "elongation 2").

[0123] The rate of change in elongation at break was calculated using the following formula.

[0124] Rate of change in elongation at break (%) = |(elongation 2) - (elongation 1)| / (elongation 1) x 100. The rate of change in elongation at break was evaluated as follows: A for less than 15%, B for 15% or more but less than 30%, C for 30% or more but less than 45%, and D for 45% or more.

[0125] The abbreviations for the compounds used in the synthesis examples and examples are as follows: BSAA: 4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic anhydride) ODPA: 3,3',4,4'-diphenylethertetracarboxylic dianhydride TDA-100: 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride PBOM: 1,1'-(4,4'-oxydibenzoyl)diimidazole (compound having the following structure)

[0126]

[0127] 4,4'-ODA: 4,4'-diaminodiphenyl ether 4,4'-CH2: 4,4'-diaminodiphenylmethane 3,3'-ODA: 3,3'-diaminodiphenyl ether mm-APB: 1,3-bis(3-aminophenoxy)benzene m-BAPS: bis[4-(3-aminophenoxy)phenyl]sulfone BAPT: 1,4-bis(4-aminobenzoyloxy)benzene 4,4'-6F: 4,4'-(hexafluoroisopropylidene)dianiline 4,4'-CO: 4,4'-diaminobenzophenone 4,4'-SO2: 4,4'-diaminodiphenyl sulfone 6FAP: 4,4'-(hexafluoroisopropylidene)bis(2-aminophenol) DCHM: 4,4'-diaminodicyclohexylmethane BZ: 4,4'-diaminobiphenyl OXT-121: an oxetane compound corresponding to the structure of formula (3) (trade name, manufactured by Toagosei Co., Ltd.) TEPIC-VL: an isocyanuric acid-modified epoxy compound (manufactured by Nissan Chemical Industries, Ltd.) EX-201-IM: resorcinol diglycidyl ether (manufactured by Nagase & Co., Ltd.) OXBP: an oxetane compound corresponding to the structure of formula (3) (trade name, manufactured by Ube Industries, Ltd.) EPOX MK R540: an oxetane compound corresponding to the structure of formula (1) except for B １ , B ２ EX-212L: a compound in which B in the structure of formula (1) is an ester bond (trade name, manufactured by Blintech Co., Ltd.) １ , B ２is an ether bond (trade name, manufactured by Nagase ChemteX Corporation) CPI-310FG: photocationic polymerization initiator (manufactured by San-Apro Co., Ltd.) GBL: gamma-butyrolactone.

[0128] The compounds used in the examples and comparative examples were synthesized by the following methods.

[0129] Synthesis Example 1 Synthesis of Polyimide (A-1) Under a dry nitrogen stream, 52.05 g (0.100 mol) of BSAA and 100 g of GBL were added to a three-necked flask and dissolved with stirring at 60°C. Subsequently, 20.02 g (0.100 mol) of 4,4'-ODA was added and stirred at 60°C for 1 hour, and then the temperature was raised to 200°C and stirred for 4 hours. After completion of the reaction, the solution was cooled to room temperature and poured into 3 L of water to obtain a white precipitate. This precipitate was collected by filtration, washed three times with water, and then dried in a forced air dryer at 50°C for 3 days to obtain a powder of polyimide (A-1).

[0130] [Synthesis Examples 2 to 19] Synthesis of Polyimides (A-2) to (A-19) Polyimides (A-2) to (A-19) were synthesized in the same manner as in Synthesis Example 1, except that the compounds and molar ratios shown in Table 2 were used as raw materials.

[0131]

[0132] *1: The number below the compound name or abbreviation indicates the Ip (unit: eV) of that compound.

[0133] Synthesis Example 20 Synthesis of Polyamide (A-20) Under a dry nitrogen stream, 35.84 g (0.100 mol) of PBOM was dissolved in 150 g of GBL at 60°C. To this solution, 23.39 g (0.08 mol) of mm-APB and 4.97 g (0.02 mol) of 4,4'-SO2 were added along with 30 g of GBL, and the mixture was allowed to react at 85°C for 3 hours. After completion of the reaction, the mixture was cooled to room temperature, and the solution was poured into 3 L of water to obtain a white precipitate. This precipitate was collected by filtration, washed three times with water, and then dried in a forced-air dryer at 50°C for 3 days to obtain a powder of polyamide (A-20).

[0134] Synthesis Example 21 Synthesis of Polyamide / Polyimide Copolymer (A-21) Under a dry nitrogen stream, 26.02 g (0.050 mol) of BSAA and 17.92 g (0.050 mol) of PBOM were dissolved in 150 g of GBL at 60°C. To this solution, 23.39 g (0.08 mol) of mm-APB and 4.97 g (0.02 mol) of 4,4'-SO2 were added along with 30 g of GBL, and the mixture was reacted at 85°C for 3 hours. The temperature was then raised to 200°C and the mixture was stirred for 3 hours. After completion of the reaction, the mixture was cooled to room temperature, and the solution was poured into 3 L of water to obtain a white precipitate. This precipitate was collected by filtration, washed three times with water, and then dried in a forced-air dryer at 50°C for 3 days to obtain a powder of polyamide / polyimide copolymer (A-21).

[0135] Synthesis Example 22 Synthesis of Polyimide Precursor (A-19) Under a dry nitrogen stream, 52.05 g (0.100 mol) of BSSA was dissolved in 150 GBL at 60°C. To this solution, 23.39 g (0.08 mol) of mm-APB and 4.97 g (0.02 mol) of 4,4'-SO2 were added along with 30 g of GBL, and the mixture was allowed to react at 60°C for 2 hours. Thereafter, a solution prepared by diluting 21.45 g (0.180 mol) of N,N-dimethylformamide dimethyl acetal (manufactured by Mitsubishi Rayon Co., Ltd.) with 20 g of GBL was added dropwise over 10 minutes. After the dropwise addition, the mixture was stirred at 60°C for 3 hours. After completion of the reaction, the mixture was cooled to room temperature, and the solution was poured into 3 L of water to obtain a white precipitate. The precipitate was collected by filtration, washed three times with water, and then dried in a forced air dryer at 50° C. for three days to obtain a powder of polyimide precursor (A-22).

[0136] [Synthesis Examples 23 to 25] Synthesis of polyimides (A-23) to (A-25) Polyimides (A-23) to (A-25) were synthesized using the molar ratios shown in Table 2 below in the same manner as in Synthesis Example 1.

[0137] [Example 1] Under yellow light, 25 g of polyimide (A-1) as component (A), 15 g of OXT-121 and 15 g of TEPIC-VL as cationically polymerizable compounds (B), and 1 g of CPI-310FG and 50 g of GBL as photocationic polymerization initiators (C) were mixed and filtered under pressure using a filter with a retention particle size of 1 µm to obtain a photosensitive resin composition.

[0138] [Examples 2 to 31, Comparative Examples 1 to 3] Photosensitive resin compositions were prepared in the same manner as in Example 1, except that the polymer compound, component (B), component (C), and solvent were mixed in the corresponding compositions shown in Table 3 to obtain the photosensitive resin compositions.

[0139]

[0140] *2: The ratio of the mass of the (B) component to the mass of the polymer compound (mass of the (B) component / mass of the polymer compound).

[0141] The photosensitive resin compositions obtained in the examples and comparative examples were evaluated for sensitivity, elongation at break, and elongation at break after reliability testing according to the evaluation methods (1) to (3) above. The evaluation results are shown in Table 4.

[0142]

Claims

1. A photosensitive resin composition comprising at least one polymeric compound selected from the group consisting of polyamides, polyimides, polyamideimides, and polybenzoxazoles (hereinafter, such polymeric compound will be referred to as "component (A)"), which has as a partial structure a diamine residue derived from an aromatic diamine having no phenolic hydroxyl group and an ionization potential (hereinafter, abbreviated as "Ip") of 6.78 eV or more (hereinafter, such aromatic diamine will be referred to as "aromatic diamine x1"), a cationically polymerizable compound (hereinafter, referred to as "component (B)"), and a photocationic polymerization initiator.

2. The photosensitive resin composition according to claim 1, wherein component (A) contains an aromatic carboxylic acid residue.

3. The photosensitive resin composition according to claim 1 or 2, wherein all or a portion of the aromatic diamine residues derived from aromatic diamine residue x1 have, in their molecular structure, at least one bond selected from the group consisting of an ether bond, a sulfonyl bond, a ketone bond, and an ester bond.

4. The photosensitive resin composition according to claim 1 or 2, wherein the content of diamine residues derived from aromatic diamine x1 in component (A) is 55 to 100 mol % when the total amount of diamine residues is 100 mol %.

5. The photosensitive resin composition according to claim 1 or 2, wherein component (A) uses, as aromatic diamine x1, both one having an Ip of 7.40 eV or more (hereinafter referred to as "aromatic diamine x1-1") and one having an Ip of 6.78 eV or more but less than 7.40 eV (hereinafter referred to as "aromatic diamine x1-2").

6. The photosensitive resin composition according to claim 5, wherein, in component (A), when the total amount of diamine residues is 100 mol %, the content of diamine residues derived from aromatic diamine x1-1 is 10 to 55 mol %, and the content of diamine residues derived from aromatic diamine x1-2 is 45 to 90 mol %.

7. The photosensitive resin composition according to claim 1 or 2, wherein all or part of component (B) is an oxetane compound.

8. A photosensitive resin composition according to claim 1 or 2, wherein the content of component (B) is 80 parts by mass or more and 150 parts by mass or less when the content of component (A) is 100 parts by mass.

9. The photosensitive resin composition according to claim 1 or 2, wherein all or part of component (B) is a compound represented by formula (1). (A １ represents an alkylene group having 1 to 20 carbon atoms or a divalent hydrocarbon group having 3 to 20 carbon atoms and an aliphatic hydrocarbon ring; B １ , B ２ each independently represents an ether bond or an ester bond.

10. A cured product obtained by curing the photosensitive resin composition according to claim 1 or 2.

11. A method for producing a cured product using the photosensitive resin composition according to claim 1 or 2, comprising the steps of: applying the photosensitive resin composition onto a substrate and drying it to form a photosensitive resin composition film; exposing the photosensitive resin composition film to light; developing the photosensitive resin composition film after exposure; and curing the photosensitive resin composition film after development.

12. An electronic component comprising the cured product according to claim 10.

13. An electronic component in which the cured product according to claim 10 is disposed as an insulating film between wirings.

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