Photosensitive resin composition, method for manufacturing a cured relief pattern, and semiconductor device

Abstract

(A) a polyimide precursor having a repeating structure represented by Formula (1): and (B) a photosensitive resin composition comprising a photoradical initiator is provided: {In Formula (1), X1 is a tetravalent organic group, Y1 is a divalent organic group, m is an integer greater than or equal to 1, R1 and R2 are hydrogen atoms, radical polymerizable groups, or organic groups represented by Formula (2); and in Formula (2), R3, R4 and Rz are each independently monovalent organic groups having 2 to 20 carbon atoms that do not contain fluorine, or, if any one of R3, R4 and Rz is a hydrogen atom, otherwise monovalent organic groups having 2 to 20 carbon atoms that do not contain fluorine atoms, and also at least one has a branched chain or cyclic structure}

Description

Technology Field

[0001] The present invention relates to a polyimide precursor, a photosensitive resin composition comprising the polyimide precursor, a method for manufacturing a cured relief pattern obtained by curing the photosensitive resin composition, a cured relief pattern, and a semiconductor device and a display device having the cured relief pattern. Background Technology

[0002] Conventionally, polyimide resins possessing excellent heat resistance, electrical properties, and mechanical properties are used as insulating materials for electronic components, as well as for passivation films, surface protection films, and interlayer insulating films of semiconductor devices. Among these polyimide resins, those provided in the form of photosensitive polyimide precursor compositions allow for the easy formation of a heat-resistant cured relief pattern film through thermal imidization treatment involving coating, exposure, development, and curing of the composition. Such photosensitive polyimide precursor compositions are characterized by enabling a significant reduction in process time compared to conventional non-photosensitive polyimide materials.

[0003] As semiconductor miniaturization progresses, an Extreme low-κ (ELK) layer with a low dielectric constant is being introduced into semiconductor devices to suppress signal delay. To reduce the dielectric constant of the ELK layer, materials with a porous structure are being used. However, a problem with such materials is that they have low mechanical strength. As a result, there is a risk that the ELK layer may be destroyed by stress applied to the ELK layer from bumps on the semiconductor surface, for example, in a solder reflow process that requires a high temperature of 260°C. In terms of i-line transmittance and low stress of a pattern protective film used as a protective film for an interlayer insulating film, for example, Patent Document 1 describes a polyimide precursor having a specific structure having polymerizable groups in the side chains for forming a low-stress cured film.

[0004] Meanwhile, recently, mounting methods for printed circuit boards of semiconductor devices are also changing in terms of improving integration density and functionality, as well as miniaturizing chip size. From the conventional mounting method using metal pins and lead-tin process solder, structures in which a polyimide film directly contacts solder bumps have come into use, such as in BGA (Ball Grid Array) and CSP (Chip Size Packaging), which enable higher density mounting. When forming such bump structures, high heat resistance and mechanical properties are required for the film. Prior art literature

[0005] Japanese Patent Publication No. 2014-201696 The problem to be solved

[0006] However, a problem with the photosensitive polyimide resin used in the ELK protective layer is, for example, its poor adhesion to aluminum forming the semiconductor electrode. As a result, delamination occurs between the polyimide resin and the substrate, raising concerns about reduced reliability of the semiconductor device.

[0007] In addition, there is a growing demand for thickening the ELK protective layer (e.g., 9 μm or thicker) to improve the reliability of semiconductor devices. Meanwhile, the polyimide resin used in the ELK protective layer is composed of a linear structural framework to impart mechanical properties. The absorption of the polyimide precursor containing such a framework at the i-line (365 nm), which is the exposure wavelength, is high, resulting in insufficient light reaching the bottom of the film during exposure. Consequently, the crosslinking efficiency of the polymer at the bottom of the film is low, making it difficult to obtain a pattern with a good shape.

[0008] The present invention aims to provide a semiconductor device capable of forming a pattern having a good shape in a thick film, and also having excellent protection of the semiconductor chip and adhesion between the surface protective film and the interlayer insulating film in the redistribution layer, and a method for manufacturing the same. means of solving the problem

[0009] The inventors, after careful consideration of the above-mentioned problems, discovered that by partially introducing a specific chemical structure as a side chain of a polyimide precursor, a thick film pattern of a photosensitive resin composition using the polyimide precursor can be formed and also exhibit good adhesion to a substrate, thereby completing the present invention. That is, the present invention is as follows.

[0010] <1>

[0011] (A) A polyimide precursor having a repeating structure represented by the following formula (1):

[0012] [Chemical Formula 1]

[0013]

[0014] {during the meal,

[0015] X1 is a tetravalent organic group, and

[0016] Y1 is a 2-valent organic group, and

[0017] m is an integer greater than or equal to 1, and

[0018] R1 and R2 are, each independently, hydrogen atoms, radical polymerization groups, or the following formula (2):

[0019] [Chemical Formula 2]

[0020]

[0021] (among the food, R3, R4 and R z are, each independently, 1 / 4 organic groups having 2 to 20 carbon atoms that do not contain fluorine, or R3, R4, and R z {where any one of them is a hydrogen atom, the others are monovalent organic groups having 2 to 20 carbon atoms that do not contain fluorine atoms, and at least one has a branched chain or cyclic structure)}, and

[0022] (B) A photosensitive resin composition comprising a photoradical initiator.

[0023] <2>

[0024] The above R3 is a photosensitive resin composition described in Item 1, which is a monovalent organic group having 3 or fewer carbon atoms.

[0025] <3>

[0026] The above R3, R4 and R z A photosensitive resin composition described in Item 1 or 2 that does not include the radical polymerizable group above.

[0027] <4>

[0028] The above radical polymerizable group is a photosensitive resin composition described in any one of items 1 to 3, which is a cause represented by the following formula (3):

[0029] [Chemical Formula 3]

[0030]

[0031] (In the formula, R5 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, R6, R7, and R8 are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and p is an integer from 1 to 10.)

[0032] <5>

[0033] At least one of R1 and R2 in the above formula (1) is a group represented by the above formula (3), and R7 and R8 are photosensitive resin compositions described in Item 4 that do not include radical polymerizable groups.

[0034] <6>

[0035] A photosensitive resin composition described in item 4 or 5, wherein, with respect to the sum of R1 and R2 in the above formula (1), the group represented by the above formula (3) is included in an amount of 20 to 80 mol%.

[0036] <7>

[0037] The above R3, R4 and R zA photosensitive resin composition described in any one of items 1 to 6, wherein one of the atoms is a hydrogen atom.

[0038] <8>

[0039] The above Y1 is a photosensitive resin composition described in any one of items 1 to 7, represented by the following formula (5) or formula (6):

[0040] [Chemical Formula 4]

[0041]

[0042] (during food, R 13 Each represents, independently, any of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group)

[0043] [Chemical Formula 5]

[0044]

[0045] (during food, R 14 Each represents, independently, either a hydrogen atom or a methyl group)

[0046] <9>

[0047] A photosensitive resin composition described in any one of items 1 to 8, wherein the above X1 is derived from at least one selected from the group consisting of the following formulas (7) to (12):

[0048] [Chemical Formula 6]

[0049]

[0050] <10>

[0051] A photosensitive resin composition described in Item 9, wherein X1 is derived from at least one selected from the group consisting of the formulas (7), (8) and (10).

[0052] <11>

[0053] (A) A polyimide precursor having a repeating structure represented by the following formula (1):

[0054] [Chemical Formula 7]

[0055]

[0056] {during the meal,

[0057] X1 is a tetravalent organic group, and

[0058] Y1 is a 2-valent organic group, and

[0059] m is an integer greater than or equal to 1, and

[0060] R1 and R2 are each independently a hydrogen atom, a radical polymerizable group, or a monovalent organic group having 2 to 20 carbon atoms that does not have a radical polymerizable group}, and

[0061] (B) A photosensitive resin composition comprising a photoradical initiator,

[0062] Structure represented by the following formula (13):

[0063] [Chemical Formula 8]

[0064]

[0065] {The definitions of X1, Y1, R1, and R2 in the equation are the same as those in Equation (1) above}

[0066] A photosensitive resin composition having, after molecular kinetics calculation by Forcite, a lowest comolecular orbital (LUMO) calculated in Dmol3 of -3.00 to -2.59 eV, and a band gap between the highest point molecular orbital (HOMO) and LUMO of 1.52 to 2.00 eV.

[0067] <12>

[0068] A photosensitive resin composition described in any one of items 1 to 11, wherein the cured film obtained by coating and exposing a wafer and heat-curing at a temperature of 280°C under a nitrogen atmosphere has a Young's modulus of 6 GPa or higher.

[0069] <13>

[0070] (1) A process of forming a photosensitive resin layer on a substrate by applying a photosensitive resin composition described in any one of items 1 to 12 onto the substrate, and

[0071] (2) A process of exposing the above photosensitive resin layer to light, and,

[0072] (3) A process of developing the photosensitive resin layer after the above exposure to form a relief pattern, and

[0073] (4) A method for manufacturing a cured relief pattern, comprising a process of forming a cured relief pattern by heat treating the above relief pattern.

[0074] <14>

[0075] A cured relief pattern comprising a cured product of a photosensitive resin composition described in any one of items 1 to 12.

[0076] <15>

[0077] A semiconductor device having a hardened relief pattern as described in Item 14. Effects of the invention

[0078] According to the present invention, a photosensitive resin composition having excellent adhesion to a metal layer in a redistribution layer and capable of forming a good thick film pattern, a method for manufacturing a cured relief pattern using the photosensitive composition, a cured relief pattern, and a semiconductor device and a display device having the cured relief pattern can be provided. Specific details for implementing the invention

[0079] Hereinafter, a form for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. Furthermore, the present invention is not limited to the present embodiment below and can be implemented with various modifications within the scope of its gist.

[0080] In the present embodiment, the photosensitive resin composition comprises (A) a polyimide precursor, (B) a photopolymerization initiator, (C) a crosslinking agent, (D) a solvent, and other components as desired. Each component is described in order below.

[0081] Additionally, as described in this specification, structures represented by the same reference numeral in the general formula may be identical or different from one another when multiple such structures exist within the molecule.

[0082] <Polyimide Precursor Composition>

[0083] (A) Polyimide precursor

[0084] As a polyimide precursor used in a photosensitive resin composition, a polyamide acid ester containing repeating units represented by the following general formula (1) is used.

[0085] [Chemical Formula 9]

[0086]

[0087] In the formula, X1 is a tetravalent organic group, Y1 is a divalent organic group, m is an integer greater than or equal to 1, and R1 and R2 are each independently a hydrogen atom, a radical polymerizable group, or the following formula (2):

[0088] [Chemical Formula 10]

[0089]

[0090] (among the food, R3, R4 and R z are, each independently, 1 / 4 organic groups having 2 to 20 carbon atoms that do not contain fluorine, or R3, R4, and R z If any one of them is a hydrogen atom, the others are organic groups having 2 to 20 carbon atoms that do not contain fluorine atoms, and at least one has a branched chain or ring structure) or organic groups having 2 to 20 carbon atoms that do not have radical polymerizable groups.

[0091] In this embodiment, multiple polyamide acid esters represented by general formula (1) may be mixed. Also, polyamide acid esters obtained by copolymerizing polyamide acid esters represented by general formula (1) may be used.

[0092] In general formula (1), the 4-valent organic group represented by X1 is not particularly limited, but preferably is an organic group having 6 to 40 carbon atoms, and more preferably, the -COOR1 group, -COOR2 group, and -CONH- group are aromatic groups or alicyclic aliphatic groups that are ortho positions to each other.

[0093] Among the general formula (1), specific examples of X1 may include those derived from at least one selected from the group consisting of the following formulas (7) to (12).

[0094] [Chemical Formula 11]

[0095]

[0096] In terms of the film properties of the cured relief pattern, the quaternary organic group represented by X1 in the above general formula (1) is preferably derived from at least one selected from the group consisting of formulas (7), (8) and (10), and more preferably includes a group derived from at least one of pyromellitic acid dianhydride (PMDA) and biphenyltetracarboxylic acid dianhydride (BPDA).

[0097] R3, R4 and R in general formula (2) z are, each independently, 1 / 4 organic groups having 2 to 20 carbon atoms that do not contain fluorine, or R3, R4, and R z If any one of them is a hydrogen atom, the others are monovalent organic groups having 2 to 20 carbon atoms that do not contain fluorine atoms, and at least one has a branched chain or cyclic structure. In terms of photosensitive properties, R3, R4, or R zIt is preferable that any one of them is an organic group having 3 or more carbon atoms, and more preferable that it is a monovalent organic group having 3 to 20 carbon atoms that does not contain fluorine. In addition, with regard to the adjustment of the polyimide precursor described later, R3, R4, and R z It is preferable that one of them is a hydrogen atom, or R3, R4, or R z It is preferable that any one of them is an organic group having 3 or fewer carbon atoms, and it is more preferable that it is a methyl group. Also, from the perspective of adhesion, R3, R4, and R z It is desirable that all of them do not contain radical polymerizable groups, and it is even more desirable that they do not contain fluorine.

[0098] In general formula (1), the radical polymerization group is preferably represented by the following formula (3) in terms of photosensitive properties:

[0099] [Chemical Formula 12]

[0100]

[0101] (In the formula, R5 is a hydrogen atom or an organic group having 1 to 10 carbon atoms, R6, R7, and R8 are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and p is an integer from 1 to 10)

[0102] In the above general formula (3), R5 is preferably a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, and more preferably a hydrogen atom or a monovalent organic group having 1 to 5 carbon atoms from the perspective of the photosensitive properties of the photosensitive resin composition. In the above general formula (3), R6 is preferably a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group from the perspective of the photosensitive properties of the photosensitive resin composition. R7 and R8 are each preferably independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and more preferably a hydrogen atom from the perspective of the photosensitive properties of the photosensitive resin composition. In the above general formula (3), p is preferably an integer from 1 to 10, and more preferably an integer from 2 to 4 from the perspective of the photosensitive properties.

[0103] Although the reason for the effects of the present invention is not certain, the inventors believe as follows. It is generally known that light absorption by polyimide precursors originates from charge transfer from the diamine portion to the acid anhydride portion. Therefore, when introducing the side chains R1 and R2 in the above formula (1), a secondary or tertiary alcohol is used, and by introducing a bulky functional group, the planarity of -X1-CONH-Y1- in the polyamic acid main chain is inhibited, and the conjugated system is cut. It is thought that this makes it possible to suppress the absorption of polyamic acid by suppressing charge transfer from the nitrogen atom to the aromatic ring of the acid anhydride.

[0104] To reduce the absorbance of the polyimide precursor, it is desirable that the energy level of the lowest comolecular orbital (LUMO) of the polyimide precursor be high, and also desirable to increase the band gap between the LUMO and the highest comolecular orbital (HOMO). In order for the polyimide precursor represented by the above formula (1) to have appropriate absorbance, the following formula (13):

[0105] [Chemical Formula 13]

[0106]

[0107] {The definitions of X1, Y1, R1, and R2 in the equation are the same as those in Equation (1) above}

[0108] After performing structural optimization by molecular dynamics calculation using Forcite on the structure represented by, it is preferable that the (LUMO) calculated with Dmol3 is -3.00 to -2.59 eV, and also preferable that the band gap between HOMO and LUMO is 1.52 to 2.00 eV, and more preferable that the LUMO is -2.85 to -2.59 eV and the band gap between HOMO and LUMO is 1.57 to 1.90 eV.

[0109] The secondary alcohols usable in this embodiment are, for example, the following formula (4):

[0110] [Chemical Formula 14]

[0111]

[0112] {In the formula, R represents, each independently, a chain-type or ring-type hydrocarbon group that does not contain fluorine atoms, which may be the same or different; preferably, each independently, is a monovalent organic group having 2 to 20 carbon atoms that does not contain fluorine atoms; more preferably, is a straight-chain or branched-chain hydrocarbon having 2 to 12 carbon atoms that does not contain fluorine atoms, which may be the same or different}

[0113] It can be represented as.

[0114] The tertiary alcohols available in this embodiment are, for example, the following formula (14):

[0115] [Chemical Formula 15]

[0116]

[0117] {In the formula, R' each independently represents a monovalent organic group, preferably a chain-type or cyclic hydrocarbon group that does not contain a fluorine atom, and more preferably, each independently represents a straight-chain or branched-chain hydrocarbon group having 2 to 20 carbon atoms that does not contain a fluorine atom, or a cyclic hydrocarbon group having 3 to 20 carbon atoms that does not contain a fluorine atom}

[0118] It can be represented as.

[0119] In addition, a side chain of a polyimide precursor represented by R1 or R2 that has a polymerizable group represented by Formula (3) forms a polymer through photopolymerization during exposure or thermal polymerization during curing, which inhibits the interaction of the polyimide with the substrate and reduces adhesion. Therefore, it is thought that by introducing a portion of a side chain that does not have a polymerizable group represented by Formula (2) into the polymer, the formation of a polymer that reduces adhesion is suppressed, thereby enabling the improvement of the adhesion of the photosensitive resin composition. In the same view, at least one of R1 and R2 in Formula (1) is a group represented by Formula (3), and it is also preferable that R7 and R8 in Formula (3) do not contain radical polymerizable groups.

[0120] In the above general formula (1), from the perspective of the photosensitive properties and mechanical properties of the photosensitive resin composition, it is preferable that the ratio of the total of monovalent organic groups represented by the above general formula (2) and the total of monovalent organic groups represented by the above general formula (3) to all of R1 and R2 is 80 mol% or more. Also, it is preferable that the ratio of the monovalent organic groups represented by the above general formula (3) to all of R1 and R2 is 20 mol% to 80 mol%. Furthermore, in the above general formula (1), it is more preferable that the ratio of the total of monovalent organic groups represented by the above general formula (2) and the total of monovalent organic groups represented by the above general formula (3) to all of R1 and R2 is 90 mol% or more, and the ratio of the monovalent organic groups represented by the above general formula (3) to all of R1 and R2 is 30 mol% to 70 mol%.

[0121] In general formula (1), there are no specific limitations on Y1, but from the perspective of Young's modulus and chemical resistance, it is preferable that Y1 be a divalent organic group containing an aromatic group. Specifically, it is preferable that Y1 be a divalent organic group containing at least one structure represented by the following general formulas (5) and (6). Also, the structure of Y1 may be a single type or a combination of two or more types.

[0122] [Chemical Formula 16]

[0123]

[0124] (during food, R 13 Each represents, independently, any of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group)

[0125] [Chemical Formula 17]

[0126]

[0127] (during food, R 14 Each represents, independently, either a hydrogen atom or a methyl group)

[0128] [(A) Method for preparing a polyimide precursor]

[0129] In the present embodiment, the polyimide precursor represented by the general formula (1) is obtained, for example, by reacting a tetracarboxylic acid dianhydride containing the aforementioned tetravalent organic group X1 having 6 to 40 carbon atoms with (a) a hydroxyl group of a monovalent organic group represented by the general formula (2) or the general formula (3) to prepare a partially esterified tetracarboxylic acid (hereinafter also referred to as an acid / ester), and then polycondensing it with a diamine containing the aforementioned divalent organic group Y1 represented by the general formula (5) or the general formula (6).

[0130] (Preparation of acids / esters)

[0131] In the present embodiment, the tetracarboxylic acid dianhydride comprising a tetravalent organic group X1 having 6 to 40 carbon atoms is, for example, pyromellitic anhydride, diphenyl ether-3,3',4,4'-tetracarboxylic acid dianhydride, benzophenone-3,3',4,4'-tetracarboxylic acid dianhydride, biphenyl-3,3',4,4'-tetracarboxylic acid 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 acid dianhydride, diphenylmethane-3,3',4,4'-tetracarboxylic acid dianhydride, Examples include 2,2-bis(3,4-phthalic anhydride)propane, 2,2-bis(3,4-phthalic anhydride)-1,1,1,3,3,3-hexafluoropropane, etc. Additionally, these may be used as a single type or as a mixture of two or more types.

[0132] In the present embodiment, the compound having a radical polymerizable group represented by the general formula (3) is, for example, 2-acryloyloxyethyl alcohol, 1-acryloyloxy-3-propyl alcohol, 2-acrylamide ethyl 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-t-butoxypropyl acrylate, 2-hydroxy-3-cyclohexyloxypropyl acrylate, 2-methacryloyloxyethyl alcohol, 1-methacryloyloxy-3-propyl alcohol, 2-methacrylamide ethyl alcohol, Examples include 2-hydroxy-3-methoxypropyl methacrylate, 2-hydroxy-3-butoxypropyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-hydroxy-3-t-butoxypropyl methacrylate, 2-hydroxy-3-cyclohexyloxypropyl methacrylate, etc.

[0133] A secondary alcohol having a group represented by the above general formula (2), not containing a fluorine atom, and not containing a polymerizable group, such as, for example, isopropyl alcohol, 2-butanol, 2-pentanol, 1-cyclopropylethanol, 3-pentanol, 2-hexanol, 3-hexanol, 2,4-dimethyl-3-pentanol, 2-heptanol, 3-heptanol, 4-heptanol, 3,3-dimethyl-2-butanol, 2-methyl-3-hexanol, 4-methyl-2-pentanol, 2,5-dimethyl-3-hexanol, 4-methyl-2-pentanol, 2-methylhexanol, 3-methylhexanol, 4-methylhexanol, 3,5-dimethylhexanol, 2-methyl-3-octanol, 2-undecanol, 3-undecanol, Examples include 5-undecanol, cyclopentanol, cyclohexanol, cycloheptanol, 1-cyclohexyl-1-butanol, exo-norborneol, 1-phenylethyl alcohol, 1-phenyl-1-propanol, 2-methoxy-2-phenylethanol, 1,3-bis(benzyloxy)-2-propanol, 3-hydroxytetrahydrofuran, tetrahydro-4-pyranol, etc.

[0134] Examples of tertiary alcohols that have a group represented by the above general formula (2), do not contain a fluorine atom, and do not contain a polymerizable group include t-butyl alcohol, t-amyl alcohol, 1-ethynyl-1-cyclopropanol, 1-adamantanol, etc.

[0135] By dissolving and mixing the above tetracarboxylic acid dianhydride and the above alcohols of (a) in a reaction solvent in the presence of a basic catalyst such as pyridine, a half-esterification reaction of the acid dianhydride is carried out to obtain the desired acid / ester. The reaction conditions are preferably such that the reaction is stirred at a reaction temperature of 20 to 50°C for 4 to 30 hours.

[0136] As the reaction solvent, it is preferable to dissolve the acid / ester and the polyimide precursor, which is a polycondensation product of the acid / ester and a diamine. Examples of reaction solvents include, for instance, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, tetramethylurea, gamma-butyrolactone, 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. These may be used individually or in combination of two or more types, as needed.

[0137] Examples of diamines containing a divalent organic group Y1 that are preferably used in the present embodiment include 2,2'-dimethyl-4,4-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 2,2'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2',3,3'-tetramethyl-4,4-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, p-phenylenediamine, 2,5-dimethyl-1,4-phenylenediamine, etc. These may be used individually or in combination of two or more types. In addition, among these, it is preferable to use 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethoxy-4,4'-diaminobiphenyl, and p-phenylenediamine, and it is even more preferable to use 2,2'-dimethyl-4,4'-diaminobiphenyl and p-phenylenediamine.

[0138] The alcohols used in the esterification reaction of the above tetracarboxylic acid dianhydride are alcohols having an olefinic double bond. Specifically, examples include 2-hydroxyethyl methacrylate, 2-methacryloyloxyethyl alcohol, glycerin diacrylate, glycerin dimethacrylate, etc., but are not limited to these. These alcohols may be used individually or in a mixture of two or more types.

[0139] Examples of organic dehydrating agents include dicyclohexylcarbodiimide (DCC), diethylcarbodiimide, diisopropylcarbodiimide, ethylcyclohexylcarbodiimide, diphenylcarbodiimide, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, and 1-cyclohexyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride.

[0140] After the reaction is finished, the by-products of the dehydration condensation agent that coexist in the reaction solution are filtered and separated as needed, and a non-solvent such as water, an aliphatic lower alcohol, or a mixture thereof is introduced into the obtained polymer component to precipitate the polymer component. Furthermore, by repeating operations such as redissolution and redeposition, the polymer is purified, and vacuum drying is performed to isolate the desired polyimide precursor. To improve the degree of purification, the solution of this polymer may be passed through a column packed with an anionic cation exchange resin swollen with a suitable organic solvent to remove ionic impurities.

[0141] (B) Photopolymerization initiator

[0142] The (B) photopolymerization initiator in this embodiment will be described. As for (B) the photopolymerization initiator, any compound conventionally used as a photopolymerization initiator for UV curing may be selected, and for example, a photoradical polymerization initiator may be used. For example, benzophenone derivatives such as benzophenone, o-methyl benzoylbenzoate, 4-benzoyl-4'-methyldiphenylketone, dibenzylketone, fluorenone; acetophenone derivatives such as 2,2'-diethoxyacetophenone, 2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenylketone; thioxanthone derivatives such as thioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, diethylthioxanthone; benzyl derivatives such as benzyl, benzyldimethylketal, benzyl-β-methoxyethylacetal; Benzoin derivatives such as benzoin and benzoin methyl ether; oximes 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-arylglycines such as N-phenylglycine; peroxides such as benzoyl perchloride; aromatic nonimidazoles, etc. are preferably listed, but are not limited to these. Additionally, these may be used as a single type or as a mixture of two or more types. Among the above (B) photopolymerization initiators, oximes are more preferred, particularly in terms of light sensitivity.

[0143] (B) The amount of photopolymerization initiator is 0.1 to 20 parts by mass per 100 parts by mass of (A) polyimide precursor, and 1 to 15 parts by mass is preferred from the perspective of photosensitivity characteristics. By incorporating (B) photopolymerization initiator in an amount of 0.1 parts by mass or more per 100 parts by mass of (A) polyimide precursor, the photosensitive resin composition has excellent photosensitivity, while by incorporating 20 parts by mass or less, the photosensitive resin composition has excellent thick film curability.

[0144] (C) Crosslinking agent

[0145] The (C) crosslinking agent in this embodiment is described. To improve the resolution of the relief pattern, a photopolymerizable monomer having unsaturated bonds may optionally be incorporated into the negative-type photosensitive resin composition. As such monomers, (meth)acrylate compounds that undergo radical polymerization reactions by a photopolymerization initiator are preferred, and are particularly, but not limited to the following, examples include mono- or diacrylate and methacrylate of ethylene glycol or polyethylene glycol, mono- or diacrylate and methacrylate of propylene glycol or polypropylene glycol, mono-, di- or triacrylate and methacrylate of glycerol, siloxane diacrylate and dimethacrylate, diacrylate and dimethacrylate of 1,4-butanediol, diacrylate and dimethacrylate of 1,6-hexanediol, diacrylate and dimethacrylate of neopentyl glycol, mono- or diacrylate and methacrylate of bisphenol A, benzene trimethacrylate, Examples of compounds include isobornyl acrylate and methacrylate, acrylamide and its derivatives, methacrylamide and its derivatives, trimethylolpropane triacrylate and methacrylate, di- or triacrylate and methacrylate of glycerol, di-, tri- or tetraacrylate and methacrylate of pentaerythritol, and ethylene oxide or propylene oxide adducts of these compounds. Among these, (meth)acrylate compounds with two or more functions are preferred, and (meth)acrylate compounds with 2 to 6 functions are more preferred.

[0146] The amount of (C) crosslinking agent, such as a monomer having unsaturated bonds in photopolymerizable form, is preferably 1 to 80 parts by mass per 100 parts by mass of (A) polyimide precursor, in order to improve relief pattern resolution.

[0147] (D) Solvent

[0148] The photosensitive resin composition of the present embodiment may contain a solvent, for example, as component (D). As a solvent, it is preferable to use a polar organic solvent in terms of solubility for (A) the polyimide precursor. Specifically, examples of solvents 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, tetramethylurea, 1,3-dimethyl-2-imidazolinone, N-cyclohexyl-2-pyrrolidone, 2-octanone, etc., and these may be used alone or in combination of two or more.

[0149] The above solvent may be used in a range of, for example, 30 to 1500 parts by mass, preferably 100 to 1000 parts by mass, with respect to 100 parts by mass of (A) polyimide precursor, depending on the desired coating film thickness and viscosity of the negative-type photosensitive resin composition.

[0150] In addition, from the perspective of improving the storage stability of the negative-type photosensitive resin composition, a solvent containing alcohols is preferred. Alcohols that can be preferably used are typically alcohols that have alcoholic hydroxyl groups within their molecules and do not have olefinic double bonds, and specific examples include alkyl alcohols such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, tert-butyl alcohol; lactic acid esters such as ethyl lactate; propylene glycol monoalkyl ethers such as propylene glycol-1-methyl ether, propylene glycol-2-methyl ether, propylene glycol-1-ethyl ether, propylene glycol-2-ethyl ether, propylene glycol-1-(n-propyl) ether, and propylene glycol-2-(n-propyl) ether; and monoalcohols such as ethylene glycol methyl ether, ethylene glycol ethyl ether, and ethylene glycol-n-propyl ether. Examples include 2-hydroxyisobutyric acid esters; and dialols such as ethylene glycol and propylene glycol. Among these, lactic acid esters, propylene glycol monoalkyl ethers, 2-hydroxyisobutyric acid esters, and ethyl alcohol are preferred, and in particular ethyl lactate, propylene glycol-1-methyl ether, propylene glycol-1-ethyl ether, and propylene glycol-1-(n-propyl) ether are more preferred.

[0151] When the solvent contains an alcohol that does not have an olefin double bond, the content of the alcohol that does not have an olefin double bond in the total solvent is preferably 5 mass% to 50 mass% based on the mass of the total solvent, and more preferably 10 mass% to 30 mass%. When the above content of the alcohol that does not have an olefin double bond is 5 mass% or more, the storage stability of the negative-type photosensitive resin composition is improved, and on the other hand, when it is 50 mass% or less, the solubility of (A) the polyimide precursor is improved, so it is preferred.

[0152] <Other ingredients>

[0153] In this embodiment, the negative-type photosensitive resin composition may additionally contain components other than the above (A) to (D) components. Examples of other components include resin components other than the above (A) polyimide precursor, sensitizers, photopolymerizable monomers having unsaturated bonds, adhesion aids, thermal polymerization inhibitors, azole compounds, hindered phenol compounds, organic titanium compounds, etc.

[0154] In this embodiment, the negative-type photosensitive resin composition may additionally contain a resin component other than the (A) polyimide precursor. Examples of resin components that may be included in the negative-type photosensitive resin composition include polyimide, polyoxazole, polyoxazole precursor, phenolic resin, polyamide, epoxy resin, siloxane resin, acrylic resin, etc. The amount of these resin components is preferably in the range of 0.01 to 20 parts by mass with respect to 100 parts by mass of the (A) polyimide precursor.

[0155] In this embodiment, a sensitizing agent may be optionally added to the negative-type photosensitive resin composition to improve light sensitivity. The sensitizers include, for example, mihler 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-dimethylaminocinnamylideneindanone, p-dimethylaminobenzylideneindanone, 2-(p-dimethylaminophenylbiphenylene)-benzothiazole, 2-(p-dimethylaminophenylvinylene)benzothiazole, 2-(p-dimethylaminophenylvinylene)isonafththiazole, 1,3-bis(4'-dimethylaminobenzal)acetone, 1,3-Bis(4'-Diethylaminobenzal)acetone, 3,3'-Carbonyl-Bis(7-Diethylaminocoumarin), 3-Acetyl-7-Dimethylaminocoumarin, 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-Morpolinobenzophenone, Isoamyl dimethylaminobenzoate, Isoamyl diethylaminobenzoate, 2-Mercaptobenzimidazole, 1-Phenyl-5-Mercaptotetrazole, 2-Mercaptobenzothiazole, Examples include 2-(p-dimethylaminostyryl)benzoxazole, 2-(p-dimethylaminostyryl)benzthiazole, 2-(p-dimethylaminostyryl)naphtho(1,2-d)thiazole, 2-(p-dimethylaminobenzoyl)styrene, etc. These can be used alone or in combination of multiple types (e.g., 2 to 5 types).

[0156] The amount of sensitizer added is preferably 0.1 to 25 parts by mass per 100 parts by mass of (A) polyimide precursor.

[0157] In this embodiment, an adhesion aid may be optionally added to the negative-type photosensitive resin composition to improve the adhesion between the film formed using the negative-type photosensitive resin composition and the substrate. As adhesion aids, for example, γ-aminopropyldimethoxysilane, N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-methacryloxypropyldimethoxymethylsilane, 3-methacryloxypropyltrimethoxysilane, dimethoxymethyl-3-piperidinopropylsilane, diethoxy-3-glycidoxypropylmethylsilane, N-(3-diethoxymethylsilylpropyl)succinimide, N-〔3-(triethoxysilyl)propyl〕phthalamic acid, benzophenone-3,3'-bis(N-〔3-triethoxysilyl〕propylamide)-4,4'-dicarboxylic acid, Examples include silane coupling agents such as benzene-1,4-bis(N-[3-triethoxysilyl]propylamide)-2,5-dicarboxylic acid, 3-(triethoxysilyl)propylsuccinic anhydride, and N-phenylaminopropyltrimethoxysilane; and aluminum-based adhesion aids such as aluminum tris(ethylacetoacetate), aluminum tris(acetylacetonate), and ethylacetoacetate aluminum diisopropylate.

[0158] Among these adhesion aids, it is preferable to use a silane coupling agent in terms of adhesion strength. The amount of adhesion aid is preferably in the range of 0.5 to 25 parts by mass per 100 parts by mass of (A) polyimide precursor.

[0159] In this embodiment, a thermal polymerization inhibitor may be optionally added to improve the stability of the viscosity and light sensitivity of the negative-type photosensitive resin composition, particularly when stored in a solution containing a solvent. Examples of thermal polymerization inhibitors used include hydroquinone, N-nitrosodiphenylamine, ptert-butylcatechol, phenothiazine, N-phenylnaphthylamine, ethylenediaminetetraacetic acid, 1,2-cyclohexanediaminetetraacetic acid, glycol etherdiaminetetraacetic acid, 2,6-di-tert-butyl-p-methylphenol, 5-nitroso-8-hydroxyquinoline, 1-nitroso-2-naphthol, 2-nitroso-1-naphthol, 2-nitroso-5-(N-ethyl-N-sulfopropylamino)phenol, N-nitroso-N-phenylhydroxylamineammonium salt, N-nitroso-N(1-naphthyl)hydroxylamineammonium salt, etc.

[0160] The amount of thermal polymerization inhibitor is preferably in the range of 0.005 to 12 parts by mass per 100 parts by mass of (A) polyimide precursor.

[0161] For example, when using a substrate made of copper or a copper alloy, an azole compound may optionally be incorporated into the negative-type photosensitive resin composition to suppress substrate discoloration. Azole compounds include, for example, 1H-triazole, 5-methyl-1H-triazole, 5-ethyl-1H-triazole, 4,5-dimethyl-1H-triazole, 5-phenyl-1H-triazole, 4-t-butyl-5-phenyl-1H-triazole, 5-hydroxyphenyl-1H-triazole, phenyltriazole, p-ethoxyphenyltriazole, 5-phenyl-1-(2-dimethylaminoethyl)triazole, 5-benzyl-1H-triazole, hydroxyphenyltriazole, 1,5-dimethyltriazole, 4,5-diethyl-1H-triazole, 1H-benzotriazole, 2-(5-methyl-2-hydroxyphenyl)benzotriazole, 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-benzotriazole, 2-(3,5-di-t-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-benzotriazole, 2-(3,5-di-t-amyl-2-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, hydroxyphenylbenzotriazole, tolyltriazole, 5-methyl-1H-benzotriazole, 4-methyl-1H-benzotriazole, 4-carboxy-1H-benzotriazole, 5-carboxy-1H-benzotriazole, 1H-tetrazole, 5-methyl-1H-tetrazole, Examples include 5-phenyl-1H-tetrazole, 5-amino-1H-tetrazole, 1-methyl-1H-tetrazole, etc. Particularly preferably, examples include tolyltriazole, 5-methyl-1H-benzotriazole, and 4-methyl-1H-benzotriazole. In addition, these azole compounds may be used as a single type or as a mixture of two or more types.

[0162] The amount of the azole compound is preferably 0.1 to 20 parts by mass per 100 parts by mass of (A) polyimide precursor, and more preferably 0.5 to 5 parts by mass from the perspective of light sensitivity characteristics. When the amount of the azole compound per 100 parts by mass of (A) polyimide precursor is 0.1 parts by mass or more, discoloration of the surface of the copper or copper alloy is suppressed when the negative-type photosensitive resin composition is formed on copper or a copper alloy, whereas when it is 20 parts by mass or less, it is preferred because the light sensitivity is excellent.

[0163] In this embodiment, a hindered phenol compound may optionally be incorporated into the negative-type photosensitive resin composition to suppress discoloration of the copper phase. Hindered phenol compounds include, for example, 2,6-di-t-butyl-4-methylphenol, 2,5-di-t-butyl-hydroquinone, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, isooctyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,4'-methylenebis(2,6-di-t-butylphenol), 4,4'-thio-bis(3-methyl-6-t-butylphenol), 4,4'-butylidene-bis(3-methyl-6-t-butylphenol), and triethyleneglycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate]. 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,2-thio-diethylenebis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], N,N' hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), 2,2'-methylene-bis(4-methyl-6-t-butylphenol), 2,2'-methylene-bis(4-ethyl-6-t-butylphenol), pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], tris(3,5-di-t-butyl-4-hydroxybenzyl)-isocyanurate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-isopropylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-s-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-Tris[4-(1-ethylpropyl)-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-Tris[4-triethylmethyl-3-hydroxy-2,6-dimethylbenzyl]-1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(3-hydroxy-2,6-dimethyl-4-phenylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5,6-trimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-Tris(4-t-butyl-6-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-Tris(4-t-butyl-6-ethyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-Tris(4-t-butyl-5,6-diethyl-3-hydroxy-2-methylbenzyl)-1,3,5-Triazine-2,4,6-(1H,3H,5H)-trione, Examples include 1,3,5-tris(4-t-butyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-3-hydroxy-2,5-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, 1,3,5-tris(4-t-butyl-5-ethyl-3-hydroxy-2-methylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, but are not limited to these. Among these, 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione is particularly preferred.

[0164] The amount of hindered phenol compound is preferably 0.1 to 20 parts by mass per 100 parts by mass of (A) polyimide precursor, and more preferably 0.5 to 10 parts by mass from the perspective of light sensitivity characteristics. When the amount of hindered phenol compound per 100 parts by mass of (A) polyimide precursor is 0.1 parts by mass or more, for example, when a negative-type photosensitive resin composition is formed on copper or a copper alloy, discoloration and corrosion of the copper or copper alloy are prevented, whereas when it is 20 parts by mass or less, it is preferred because the light sensitivity is excellent.

[0165] In this embodiment, an organic titanium compound may be used to improve elongation after a moist heat endurance test. There are no particular limitations on the organic titanium compound that can be used, as long as an organic chemical substance is bonded to a titanium atom via a covalent or ionic bond.

[0166] Specific examples of organic titanium compounds are shown in I) to VII) below:

[0167] I) Titanium chelate compounds: Among these, titanium chelates having two or more alkoxy groups are preferred in that storage stability and good patterning of the negative-type photosensitive resin composition are obtained, and specific examples include titanium bis(triethanolamine)diisopropoxide, titanium di(n-butoxide)bis(2,4-pentanedianate), titanium diisopropoxide bis(2,4-pentanedianate), titanium diisopropoxide bis(tetramethylheptanedianate), titanium diisopropoxide bis(ethylacetoacetate), etc.

[0168] II) Tetraalkoxytitanine compounds: e.g., titanium tetra(n-butoxide), titanium tetraethoxide, titanium tetra(2-ethylhexoxide), titanium tetraisobutoxide, titanium tetraisopropoxide, titanium tetramethoxide, titanium tetramethoxypropoxide, titanium tetramethylphenoxide, titanium tetra(n-nonyl oxide), titanium tetra(n-propoxide), titanium tetrastearyl oxide, titanium tetrakis[bis{2,2-(allyloxymethyl)butoxide}], etc.

[0169] III) Titanocene compounds: e.g., pentamethylcyclopentadienyltitanium trimethoxide, bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluorophenyl)titanium, bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluoro-3-(1H-pyrrole-1-yl)phenyl)titanium, etc.

[0170] IV) Monoalkoxytitanine compounds: Examples include titanium trith(dioctyl phosphate)isopropoxide, titanium trith(dodecylbenzenesulfonate)isopropoxide, etc.

[0171] V) Titanium oxide compounds: Examples include titanium oxide bis(pentanedianate), titanium oxide bis(tetramethylheptanedianate), phthalocyanine titanium oxide, etc.

[0172] VI) Titanium tetraacetylacetonate compounds: e.g., titanium tetraacetylacetonate, etc.

[0173] VII) Titanate coupling agents: e.g., isopropyltridodecylbenzenesulfonyltitanate, etc.

[0174] Among the above I) to VII), it is preferable that the organic titanium compound is at least one compound selected from the group consisting of I) titanium chelate compounds, II) tetraalkoxytitanine compounds, and III) titanocene compounds, in order to exhibit better chemical resistance. In particular, titanium diisopropoxide bis(ethylacetoacetate), titanium tetra(n-butoxide), and bis(η5-2,4-cyclopentadiene-1-yl)bis(2,6-difluoro-3-(1H-pyrrole-1-yl)phenyl)titanium are preferred.

[0175] The amount of these organic titanium compounds added is preferably 0.01 to 10 parts by mass per 100 parts by mass of the polyimide precursor used as component (A), and more preferably 0.1 to 2 parts by mass. If the amount of organic titanium compounds added is 0.01 parts by mass or more, adhesion is easily achieved, and if it is 10 parts by mass or less, storage stability is easily achieved.

[0176] In the photosensitive resin composition of the present embodiment, it is preferable that the total amount of components excluding (A) polyimide precursor among the total solid content included in the photosensitive resin composition is 26 mass% or more and less than 60 mass% with respect to (A) polyimide precursor. By making the total amount of components excluding (A) polyimide precursor 26 mass% or more, the absolute value of the initial development time after the coating process and bake treatment can be shortened, leading to an improvement in throughput in the semiconductor manufacturing process. In addition, by making the total amount of components excluding (A) polyimide precursor less than 60 mass%, the film properties after the moist heat endurance test can be maintained.

[0177] In the photosensitive resin composition related to the present embodiment, it is preferable that the Young's modulus of the cured film obtained by coating and exposing a wafer and heat-curing it at a temperature of 280°C under a nitrogen atmosphere, with regard to protecting the ELK layer of a semiconductor device, be 6 GPa or higher.

[0178] In one embodiment, a cured relief pattern comprising a cured product of the photosensitive resin composition described above may also be provided, and the adhesion to the metal layer in the redistribution layer or the formation of a thick film is excellent.

[0179] <Method for Manufacturing a Cured Relief Pattern>

[0180] In this embodiment, the following processes (1) to (4):

[0181] (1) A process of forming a photosensitive resin layer on a substrate by applying the photosensitive resin composition of the above-described embodiment onto a substrate,

[0182] (2) Process of exposing a photosensitive resin layer,

[0183] (3) A process of developing a photosensitive resin layer after exposure to form a relief pattern, and

[0184] (4) A method for manufacturing a cured relief pattern can be provided, comprising a process of heat-treating the relief pattern to form a cured relief pattern.

[0185] The following describes each process.

[0186] (1) A process of applying a negative-type photosensitive resin composition onto a substrate to form a photosensitive resin layer on the substrate.

[0187] In this process, the photosensitive resin composition of the embodiment described above is applied onto a substrate, and if necessary, subsequently dried to form a photosensitive resin layer. In the method for manufacturing a cured relief pattern, negative-type and positive-type photosensitive resin compositions may be used, and among the two types, it is preferable to apply the negative-type photosensitive resin composition to the substrate. As for the application method, methods conventionally used for applying photosensitive resin compositions, such as applying with a spin coater, bar coater, blade coater, curtain coater, screen printer, etc., or spraying with a spray coater, may be used.

[0188] If necessary, a coating film made of a photosensitive resin composition can be dried, and drying methods such as air drying, heating drying by an oven or hot plate, or vacuum drying are used. In addition, it is preferable to dry the coating film under conditions where imidization of the (A) polyimide precursor in the negative-type photosensitive resin composition does not occur. Specifically, when air drying or heating drying is performed, drying can be carried out at 20°C to 140°C for 1 minute to 1 hour. It is preferable to heat at 100°C to 120°C for 230 seconds to 250 seconds, and more preferable to heat at 110°C for 240 seconds. By carrying out process (1) as described above, a photosensitive resin layer can be formed on a substrate.

[0189] (2) Process of exposing the photosensitive resin layer to light

[0190] In this process, the photosensitive resin layer formed in the above (1) process is exposed using an exposure device such as a contact aligner, mirror projection, or stepper, with a photomask or reticle having a pattern interposed therein, or by a direct ultraviolet light source.

[0191] Afterwards, for purposes such as improving light sensitivity, post-exposure baking (PEB) and / or pre-development baking may be performed at any combination of temperature and time as needed. The range of baking conditions is preferably such that the temperature is 40°C to 120°C and the time is preferably 10 seconds to 240 seconds, but is not limited to this range as long as it does not impair the properties of the photosensitive resin composition.

[0192] (3) A process of developing a photosensitive resin layer after exposure to form a relief pattern

[0193] In this process, unexposed portions of the photosensitive resin layer are developed and removed after exposure. As a developing method for the photosensitive resin layer after exposure (irradiation), any method may be selected from conventionally known photoresist developing methods, such as the rotary spray method, the puddle method, or the immersion method involving ultrasonic treatment. Additionally, if necessary, a post-development bake may be performed using any combination of temperature and time for the purpose of adjusting the shape of the relief pattern after development.

[0194] As for the developer used for development, for example, a solvent for the negative-type photosensitive resin composition, or a combination of the solvent and a solvent is preferred. For the solvent, for example, N-methyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N,N-dimethylacetamide, cyclopentanone, cyclohexanone, γ-butyrolactone, α-acetyl-γ-butyrolactone, etc. are preferred. For the solvent, for example, toluene, xylene, methanol, ethanol, isopropyl alcohol, ethyl lactate, propylene glycol methyl ether acetate, and water, etc. When using a mixture of the solvent and the solvent, it is preferable to adjust the ratio of the solvent to the solvent according to the solubility of the polymer in the negative-type photosensitive resin composition. In addition, two or more types of each solvent, for example, a combination of several types, may be used.

[0195] (4) A process of forming a hardened relief pattern by heat-treating the relief pattern.

[0196] In this process, the relief pattern obtained by the above phenomenon is heated to dilute the photosensitive component, and at the same time, (A) the polyimide precursor is imidized to convert it into a cured relief pattern made of polyimide. Various methods can be selected for heat curing, such as using a hot plate, using an oven, or using a heating oven capable of setting a temperature program. Heating can be performed, for example, at 200°C to 400°C for 30 minutes to 5 hours. Air may be used as the atmosphere gas during heat curing, or an inert gas such as nitrogen or argon may be used. From the perspective of controlling the Young's modulus of the cured film, heat curing can be performed under a nitrogen atmosphere, preferably at a temperature of 200°C to 400°C, more preferably at a temperature of 250°C to 300°C, and even more preferably at a temperature of 270°C to 290°C.

[0197] <Semiconductor Device>

[0198] In the present embodiment, a semiconductor device is also provided having a cured relief pattern obtained by the method for manufacturing a cured relief pattern described above. Accordingly, a semiconductor device having a substrate which is a semiconductor element and a cured relief pattern of polyimide formed on the substrate by the method for manufacturing a cured relief pattern described above may be provided.

[0199] Furthermore, the present invention may also be applied to a method for manufacturing a semiconductor device that uses a semiconductor device as a substrate and includes the method for manufacturing a cured relief pattern described above as part of the process. The semiconductor device of the present invention may be manufactured by forming the cured relief pattern formed by the method for manufacturing a cured relief pattern above as a surface protective film, an interlayer insulating film, an insulating film for redistribution, a protective film for a flip-chip device, or a protective film for a semiconductor device having a bump structure, and by combining it with a known method for manufacturing a semiconductor device.

[0200] <Display device>

[0201] In the present embodiment, a display device is provided having a display element and a cured film formed on the upper surface of the display element, wherein the cured film is the cured relief pattern described above. Here, the cured relief pattern may be laminated in direct contact with the display element or laminated with another layer in between. For example, the cured film may include a surface protection film, an insulating film, and a planarization film for a TFT liquid crystal display element and a color filter element, a protrusion for an MVA type liquid crystal display device, and a barrier for an organic EL element cathode.

[0202] In addition to applications for semiconductor devices as described above, the photosensitive resin composition of the present invention is also useful for applications such as interlayer insulating films of multilayer circuits, cover coats of flexible copper coating plates, solder resist films, and liquid crystal alignment films.

[0203] Examples

[0204] Hereinafter, embodiments carried out to clarify the effects of the present invention will be described, but the present invention is not limited to the embodiments described in the embodiments. In the embodiments, the following materials and measurement methods were used.

[0205] <Measurement and Evaluation Methods>

[0206] (1) i-line absorbance measurement

[0207] The i-line absorbance of the polyimide precursor was measured by preparing an NMP solution containing 0.1 wt% of the polyimide precursor, filling it into a 1 cm quartz cell, and using a Shimadzu Corporation UV-1800 instrument at a medium scan speed and a sampling pitch of 0.5 nm. The i-line absorbance of the polyimide precursor as a polymer sample was evaluated according to the following criteria:

[0208] A : Absorbance less than 1.0 ;

[0209] B : Absorbance 1.0 or higher and 1.2 or lower ;

[0210] C: Absorbance exceeds 1.2.

[0211] (2) Pattern formation (lithography) evaluation

[0212] The resin composition prepared in the formulation example was spin-coated onto a 6-inch silicon wafer substrate such that the film thickness after curing was 9 μm, and pre-baked at 110°C for 4 minutes. The obtained film was exposed by irradiating an i-line with an exposure amount of 450 mJ / cm² using a stepper NSR2005i8A (manufactured by Nikon) having an exposure wavelength of i-line (365 nm) through a reticle having a test pattern formed thereon. Next, using a developer D-SPIN (manufactured by SOKUDO), rotary spray development was performed at 23°C with cyclopentanone as the developer for a time multiplied by 1.4 until the unexposed area was completely dissolved and disappeared, and then rotary spray rinsing with propylene glycol monomethyl ether acetate for 10 seconds was performed to obtain a relief pattern formed by the resin film. Next, curing was performed using a bell-shaped curer VF200B (manufactured by Koyo Thermosystem Co., Ltd.) at 280°C for 2 hours under a nitrogen atmosphere to obtain a cured relief pattern.

[0213] For each obtained pattern, the pattern shape was observed using a scanning electron microscope (Hitachi High-Technologies S-4800). Regarding resolution, a pattern having multiple apertures of different areas was formed by exposure through a reticle having a test pattern formed thereon in the same manner as above. Among the obtained patterns that had no residue at the bottom and had a normal taper angle of the sidewall, the length of the aperture edge of the mask corresponding to the one with the minimum area was defined as the minimum aperture. In addition, the photosensitive resin composition adjusted in the formulation example was evaluated according to the following criteria:

[0214] A : Minimum aperture less than 8 µm ;

[0215] B: Minimum aperture of 8 µm or more and 10 µm or less;

[0216] C: The minimum aperture exceeds 10 μm.

[0217] (3) Close evaluation (mandatory test)

[0218] The resin composition prepared in the formulation example was spin-coated onto a 6-inch silicon wafer substrate having an aluminum (Al) deposition layer formed on its surface so that the film thickness after curing was 9 μm, and pre-baked at 110°C for 4 minutes. Then, a heat curing treatment was performed at 280°C for 2 hours using a bell-shaped curer (manufactured by Koyo Lindberg, model name VF-2000B) to produce a wafer with a polyimide resin film formed thereon.

[0219] The peel strength may be the peel strength between the glass substrate and the polyimide film, measured according to the 180-degree (°) peeling method of JISK6854-1 using a sample in which a polyimide film is formed on a glass substrate. The peel strength was measured under the following conditions:

[0220] Device Name: RTG-1210 (Manufactured by A & D Co., Ltd.)

[0221] Measured temperature: Room temperature

[0222] Peeling speed: 50 mm / min

[0223] Atmosphere: Waiting

[0224] Measurement sample width: 5 mm.

[0225] In addition, the Al adhesion of the photosensitive resin composition was evaluated according to the following criteria:

[0226] A : Peel strength exceeds 0.3 N / mm ;

[0227] B: Peel strength 0.2 or more and 0.3 N / mm or less;

[0228] C: Peel strength less than 0.2 N / mm.

[0229] <Preparation Example 1> (Polymer A: Synthesis of polyimide precursor)

[0230] (Reaction Solution I)

[0231] 19.63 g (0.09 mol) of pyromellitic acid anhydride (PMDA) as acid anhydride 1 and 19.13 g (0.19 mol) of 3,3-dimethyl-2-butanol as side chain 1 were placed in a 200 mL three-necked flask, 53 g of γ-butyrolactone and 14.24 g (0.18 mol) of pyridine were added, and the mixture was stirred at room temperature for 24 hours to obtain reaction solution I.

[0232] (Reaction Solution II)

[0233] 18.61 g (0.06 mol) of 4,4'-oxydiphthalic dianhydride (ODPA) as acid anhydride 2 and 16.24 g (0.12 mol) of 2-hydroxyethyl methacrylate (HEMA) as side chain 2 were placed in a 1-liter separable flask, 44.35 g of γ-butyrolactone and 9.49 g (0.12 mol) of pyridine were added, and the mixture was stirred at room temperature for 16 hours to obtain reaction solution II.

[0234] Next, reaction solution I and reaction solution II were mixed and cooled to below 0°C, and a solution of 60.98 g (0.15 mol) of dicyclohexylcarbodiimide (DCC) dissolved in 60.00 g of γ-butyrolactone was added to the reaction mixture over a period of 20 minutes while stirring.

[0235] While continuously maintaining the reaction temperature at 2 ℃ or lower, a solution of 27.86 g (0.13 mol) of 2,2'-dimethylbiphenyl-4,4'-diamine (m-TB) as a diamine dissolved in 80.00 g of γ-butyrolactone was added dropwise over a period of 30 minutes.

[0236] After that, the reaction solution was heated to room temperature and stirred at room temperature for 4 hours. Then, 13.66 g of ethanol was added as a terminal encapsulant and stirred for 30 minutes, and the precipitate formed in the reaction mixture was removed by filtration to obtain the reaction solution.

[0237] 3 L of ethanol was added to the obtained reaction solution to produce a precipitate consisting of an unpurified polymer. The produced unpurified polymer was separated by filtration and dissolved in 600 g of γ-butyrolactone to obtain an unpurified polymer solution. The obtained unpurified polymer solution was added dropwise to 6 L of water to precipitate the polymer, and after separating the obtained precipitate by filtration, it was vacuum dried at 40 ℃ for 72 hours to obtain a powdered polymer (polyimide precursor (polymer A)). The polymer was evaluated as A with an i-line absorbance of 0.92. Furthermore, regarding the structure of the obtained polymer represented by the above general formula (13), the simulation software "Forcite" was used under the conditions listed in Table 1 below:

[0238]

[0239] Structural optimization was performed in, and additionally, using the calculation program "Dmol3", under the conditions listed in Table 2 below:

[0240]

[0241] The band gap between the lowest comolecular orbital (LUMO) and the highest comolecular orbital (HOMO)-LUMO was calculated.

[0242] <Preparation Examples 2–10> (Polymers B–J: Synthesis of polyimide precursors)

[0243] The acid anhydride, side chain, and diamine of reaction solution I and reaction solution II in Preparation Example 1 were substituted with the combinations shown in Table 3, polymers B to J were synthesized in the same order as the synthesis example of Preparation Example 1, and the i-line absorbance of the polymers was evaluated.

[0244] <Preparation Example 11> (Polymer K: Synthesis of Polyimide Precursor)

[0245] 18.61 g (0.06 mol) of 4,4'-oxydiphthalic dianhydride (ODPA) and 19.63 g (0.09 mol) of pyromellitic anhydride (PMDA) as acid anhydrides, and 40.61 g (0.15 mol) of 2-hydroxyethyl methacrylate (HEMA) as a side chain were placed in a 1-liter separable flask, 102.58 g of γ-butyrolactone and 23.73 g (0.30 mol) of pyridine were added, and the mixture was stirred at room temperature for 16 hours.

[0246] Next, the reaction mixture was cooled to below 0°C, and a solution of 60.98 g (0.15 mol) of dicyclohexylcarbodiimide (DCC) dissolved in 60.00 g of γ-butyrolactone was added over 20 minutes while stirring.

[0247] While continuously maintaining the reaction temperature at 2 ℃ or lower, a solution of 27.29 g (0.13 mol) of 2,2'-dimethylbiphenyl-4,4'-diamine (m-TB) as a diamine dissolved in 80.00 g of γ-butyrolactone was added dropwise over 30 minutes.

[0248] After that, the reaction solution was heated to room temperature and stirred at room temperature for 4 hours. Then, 13.66 g of ethanol was added as a terminal encapsulant and stirred for 30 minutes, and the precipitate formed in the reaction mixture was removed by filtration to obtain the reaction solution.

[0249] 3 L of ethanol was added to the obtained reaction solution to produce a precipitate consisting of an unpurified polymer. The resulting unpurified polymer was separated by filtration and dissolved in 600 g of γ-butyrolactone to obtain an unpurified polymer solution. The obtained unpurified polymer solution was added dropwise to 6 L of water to precipitate the polymer, and the obtained precipitate was separated by filtration and vacuum dried at 40 ℃ for 72 hours to obtain a powdered polymer (polyimide precursor (polymer K)). The i-line absorbance of the polymer was measured, and the result was Evaluation C.

[0250] <Preparation Example 12> (Polymer M: Synthesis of polyimide precursor)

[0251] The acid anhydride and diamine in Preparation Example 11 were substituted with the combinations shown in Table 3, polymer M was synthesized in the same order as the synthesis example of Preparation Example 11, and the i-line absorbance of the polymer was evaluated.

[0252]

[0253] <Examples 1–8, Comparative Examples 1–4>

[0254] 10.00 g of polymers A to M obtained in the preparation example, 0.50 g of 1-phenyl-2-[(benzoylyoxy)imino]-1-propanone as a photopolymerization initiator, 1.40 g of tetraethylene glycol dimethacrylate as a crosslinking agent, 1.20 g of N-phenyldiethanolamine as a sensitizer, and 0.05 g of 7-(diethylamino)coumarin-3-ethyl carboxylate were dissolved in 18.49 g of γ-butyrolactone, and filtered using a microfilter with a pore size of 1 μm to prepare a photosensitive resin composition. The evaluation results of the pattern formation ability and adhesion of the polymers used in each example and comparative example, and the photosensitive resin composition are summarized in Table 4.

[0255]

[0256] As is evident from the above examples, i-line absorbance was suppressed by introducing side chains having a branched structure into the polymer. The photosensitive resin composition using the said polymer exhibited good pattern formation performance in thick films. Furthermore, a significant improvement was observed in the adhesion to aluminum of the photosensitive resin composition using a polymer with non-crosslinkable side chains.

[0257] Industrial applicability

[0258] By using the photosensitive resin composition according to the present invention, it is possible to form an insulating layer that exhibits excellent adhesion to a substrate after the curing treatment of a coating film, and also to stably open via patterns, and it can be preferably used in the field of photosensitive materials useful for manufacturing electrical and electronic materials such as semiconductor devices and multilayer wiring boards.

Claims

Claim 1 (A) A polyimide precursor having a repeating structure represented by the following formula (1): {In the formula, X1 is a tetravalent organic group, Y1 is a divalent organic group, m is an integer greater than or equal to 1, and R1 and R2 are each independently a hydrogen atom, a radical polymerizable group, or the following formula (2): (among the food, R3, R4 and R z are, each independently, 1 / 4 organic groups having 2 to 20 carbon atoms that do not contain fluorine, or R3, R4, and R z A photosensitive resin composition comprising: (B) an organic group having 1 to 20 carbon atoms that does not contain fluorine atoms, wherein at least one of which is a hydrogen atom, is represented by an organic group having a branched chain or cyclic structure, and at least one of which is an organic group represented by formula (2), and a photoradical initiator. Claim 2 In claim 1, the above R3 is a photosensitive resin composition having a monovalent organic group with 3 or fewer carbon atoms. Claim 3 In claim 1 or 2, the above R3, R4 and R z A photosensitive resin composition that does not include the above-mentioned radical polymerizable group. Claim 4 A photosensitive resin composition according to claim 1 or 2, wherein the radical polymerizable group is a cause represented by the following formula (3): (In the formula, R5 is a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms, R6, R7, and R8 are each independently a hydrogen atom or a monovalent organic group having 1 to 3 carbon atoms, and p is an integer from 1 to 10.) Claim 5 In claim 4, at least one of R1 and R2 in formula (1) is a group represented by formula (3), and R7 and R8 are photosensitive resin compositions that do not include radical polymerizable groups. Claim 6 A photosensitive resin composition according to claim 4, wherein, with respect to the sum of R1 and R2 in formula (1), the group represented by formula (3) is included in an amount of 20 to 80 mol%. Claim 7 In claim 1 or 2, the above R3, R4 and R z A photosensitive resin composition in which one of the atoms is a hydrogen atom. Claim 8 In claim 1 or 2, the above Y1 is a photosensitive resin composition represented by the following formula (5) or formula (6): (during food, R 13 Each represents, independently, any of a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group) (during food, R 14 Each represents, independently, either a hydrogen atom or a methyl group) Claim 9 A photosensitive resin composition according to claim 1 or 2, wherein X1 is derived from at least one selected from the group consisting of the following formulas (7) to (12): Claim 10 A photosensitive resin composition according to claim 9, wherein X1 is derived from at least one selected from the group consisting of formulas (7), (8) and (10). Claim 11 (A) A polyimide precursor having a repeating structure represented by the following formula (1): {In the formula, X1 is a 4-valent organic group, Y1 is a 2-valent organic group, m is an integer greater than or equal to 1, and R1 and R2 are each independently a hydrogen atom, a radical polymerizable group, or a 1-valent organic group having 2 to 20 carbon atoms that does not have a radical polymerizable group, or the following formula (2): (among the food, R3, R4 and R z are, each independently, 1 / 4 organic groups having 2 to 20 carbon atoms that do not contain fluorine, or R3, R4, and R z (B) a photosensitive resin composition comprising a photoradical initiator, wherein the other is a monovalent organic group having 1 to 20 carbon atoms that does not contain fluorine atoms, and at least one has a branched chain or cyclic structure, wherein at least one of R1 and R2 is an organic group represented by formula (2), and (B) a structure represented by the following formula (13): A photosensitive resin composition having, after molecular kinetics calculation by Forcite of {the definitions of X1, Y1, R1 and R2 in the formula are the same as in the above formula (1)}, a lowest comolecular orbital (LUMO) calculated with Dmol3 is -3.00 to -2.59 eV, and a band gap between the highest point molecular orbital (HOMO) and LUMO is 1.52 to 2.00 eV. Claim 12 A photosensitive resin composition according to claim 1 or 11, wherein the cured film obtained by coating and exposing a wafer and heat-curing at a temperature of 280°C under a nitrogen atmosphere has a Young's modulus of 6 GPa or more. Claim 13 (1) a process of forming a photosensitive resin layer on a substrate by applying a photosensitive resin composition described in claim 1 or claim 11 onto the substrate, (2) a process of exposing the photosensitive resin layer to light, (3) a process of developing the photosensitive resin layer after exposure to form a relief pattern, and (4) a process of forming a cured relief pattern by heat treating the relief pattern. Claim 14 A cured relief pattern comprising a cured product of the photosensitive resin composition described in claim 1 or claim 11. Claim 15 A semiconductor device having a hardened relief pattern as described in claim 14.

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