Photosensitive resin composition

Abstract

The present invention provides a photosensitive resin composition having excellent resolution and a cured product having excellent under-cut resistance. The photosensitive resin composition of the present invention contains (A) a resin containing an ethylenically unsaturated group and a carboxyl group, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a volatile component, wherein the weight loss rate (%) of the photosensitive resin composition when dried at 130°C for 15 minutes is set as a, and the weight loss rate (%) of the photosensitive resin composition when dried at 180°C for 15 minutes is set as b, and the following formula (1) and formula (2) are satisfied: V = a 2 + b 2 wherein V ≤ 30 (1) and a / b ≤ 0.6 (2).

Description

Technical Field

[0001] This invention relates to photosensitive resin compositions. It also relates to photosensitive films obtained using these compositions, photosensitive films with supports, printed wiring boards, and semiconductor devices. Background Technology

[0002] In printed wiring boards, a solder resist layer is sometimes provided as a permanent protective film to prevent solder from adhering to areas where solder is not needed and to inhibit corrosion of the circuit board. As a solder resist layer, a photosensitive resin composition, such as that described in Patent Document 1, is generally used.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2014-115672. Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] The photosensitive resin composition used in solder resist layers is generally required to have high resolution and good insulation properties. In recent years, solder resist layers have been required to have fine opening patterns, exposing a portion of the conductor layer with wiring patterns for soldering connections between substrates. From the viewpoint of adhesion, the shape of these openings is required to be non-conical. Here, a conical opening shape refers to a shape that widens towards the inside. In this application, the property of such an opening shape not being conical is sometimes referred to as excellent "undercut resistance."

[0008] The objective of this invention is to provide: a photosensitive resin composition that yields a cured product with excellent undercut resistance and excellent resolution, a photosensitive film obtained from the photosensitive resin composition, a photosensitive film with a support, a printed wiring board, and a semiconductor device.

[0009] Technical solutions adopted to solve technical problems

[0010] The inventors conducted careful research and discovered that by adjusting the components of the resin composition according to the condition that the weight loss rate of the photosensitive film meets the specified relationship, the undercut resistance and resolution are improved, thereby completing the present invention.

[0011] That is, the present invention includes the following:

[0012] [1] A photosensitive resin composition comprising the following components (A) to (D),

[0013] (A) Resins containing olefinic unsaturated groups and carboxyl groups,

[0014] (B) Photopolymerization initiators,

[0015] (C) Epoxy resin, and

[0016] (D) Volatile components, wherein the weight loss rate (%) of the photosensitive resin composition after drying at 130°C for 15 minutes is defined as a, and the weight loss rate (%) of the photosensitive resin composition after drying at 180°C for 15 minutes is defined as b, and the following relationship between equations (1) and (2) is satisfied:

[0017] V = a 2 +b 2 Where V≤30 (1)

[0018] a / b≤0.6 (2)

[0019] [2] The photosensitive resin composition according to [1] further comprises (F) an inorganic filler material;

[0020] [3] The photosensitive resin composition according to [1] or [2], wherein component (A) comprises an acid-modified unsaturated epoxy ester resin;

[0021] [4] The photosensitive resin composition according to any one of [1] to [3], wherein component (A) comprises acid-modified epoxy (meth)acrylate;

[0022] [5] The photosensitive resin composition according to any one of [1] to [4], wherein component (A) comprises: any one of an acid-modified epoxy (meth)acrylate containing a naphthalene skeleton and an acid-modified epoxy (meth)acrylate containing a bisphenol skeleton;

[0023] [6] The photosensitive resin composition according to any one of [1] to [5], wherein component (B) comprises any one of an acylphosphine oxide photopolymerization initiator and an oxime ester photopolymerization initiator;

[0024] [7] The photosensitive resin composition according to any one of [1] to [6], wherein component (D) has any one of ketones and glycol ethers;

[0025] [8] A photosensitive film comprising any one of the photosensitive resin compositions described in [1] to [7];

[0026] [9] A photosensitive film with a support, having a support and a photosensitive resin composition layer comprising any one of [1] to [7] disposed on the support;

[0027]

[10] A printed wiring board comprising an insulating layer formed by curing a photosensitive resin composition according to any one of [1] to [7];

[0028]

[11] A semiconductor device, wherein the insulating layer is a solder resist layer;

[0029]

[12] A semiconductor device comprising the printed wiring board described in

[10] or

[11] .

[0030] The effects of the invention

[0031] If the present invention is adopted, it is possible to provide: a photosensitive resin composition that yields a cured product with excellent undercut resistance and excellent resolution, a photosensitive film obtained from the photosensitive resin composition, a photosensitive film with a support, a printed wiring board, and a semiconductor device. Detailed Implementation

[0032] The photosensitive resin composition, photosensitive film, photosensitive film with support, printed wiring board, and semiconductor device of the present invention will be described in detail below.

[0033] [Photosensitive Resin Composition]

[0034] The photosensitive resin composition of the present invention comprises (A) a resin containing olefinic unsaturated groups and carboxyl groups, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a volatile component. When the weight loss rate (%) of the photosensitive resin composition after drying at 130°C for 15 minutes is defined as a, and the weight loss rate (%) of the photosensitive resin composition after drying at 180°C for 15 minutes is defined as b, the following relationships between equations (1) and (2) are satisfied:

[0035] V = a 2 +b 2 Where V≤30 (1)

[0036] a / b≤0.6 (2).

[0037] In this invention, by adjusting the components of the photosensitive resin composition according to a specified relationship of weight loss rate, a photosensitive resin composition with excellent undercut resistance and excellent resolution can be provided. Furthermore, a cured product with excellent embedding properties can generally also be obtained. The inventors focused on the amount of volatile components volatilized from the photosensitive resin composition upon heating. As a result, it was found that if the amount of volatilization at a heating temperature of 130°C and the amount of volatilization at a heating temperature of 180°C satisfy the above-described formulas (1) and (2), a cured product with excellent undercut resistance can be obtained. To the knowledge of the inventors, the technical concept of adjusting the volatile components according to a specified relationship of volatilization amount is not previously proposed.

[0038] The photosensitive resin composition may be combined with components (A) to (D) to further include any other components. Examples of such other components include (E) reactive diluents, (F) inorganic fillers, and (G) other additives. The components contained in the photosensitive resin composition will be described in detail below.

[0039] <(A) Resins containing olefinic unsaturated groups and carboxyl groups>

[0040] The photosensitive resin composition includes, as component (A), a resin containing olefinic unsaturated groups and carboxyl groups. By including component (A) in the photosensitive resin composition, the developability can be improved.

[0041] Examples of olefinic unsaturated groups include vinyl, allyl, propargyl, butenyl, ethynyl, phenylethynyl, maleimide, nadiimide, and (meth)acryloyl. From the viewpoint of the reactivity of photoradical polymerization, (meth)acryloyl is preferred. "(meth)acryloyl" refers to both methacryloyl and acryloyl groups.

[0042] (A) The component has an olefinic unsaturated group and a carboxyl group, and any compound that can be photopolymerized and alkaline developable can be used, preferably, for example, a resin that has a carboxyl group and two or more olefinic unsaturated groups in one molecule.

[0043] Examples of resins containing olefinic unsaturated groups and carboxyl groups include acid-modified unsaturated epoxy ester resins, which are obtained by reacting unsaturated carboxylic acids with epoxy compounds and then with acid anhydrides. Specifically, an acid-modified unsaturated epoxy ester resin can be obtained by reacting an unsaturated carboxylic acid with an epoxy compound, and then by reacting the unsaturated epoxy ester resin with an acid anhydride.

[0044] As epoxy compounds, any compound containing an epoxy group within its molecule can be used. Examples include: epoxy-containing copolymers, bisphenol A type epoxy resins, hydrogenated bisphenol A type epoxy resins, bisphenol F type epoxy resins, hydrogenated bisphenol F type epoxy resins, bisphenol S type epoxy resins, modified bisphenol F type epoxy resins modified by reacting epichlorohydrin with bisphenol F type epoxy resin to achieve trifunctionality or higher, etc., as well as biphenol type epoxy resins, tetramethyl... Biphenol-type epoxy resins, phenolic varnish epoxy resins such as biphenol type, phenolic varnish epoxy resins such as phenol, cresol, bisphenol A type, and alkylphenol varnish epoxy resins, fluorinated epoxy resins such as bisphenol AF type and perfluoroalkyl type epoxy resins; naphthalene-type epoxy resins, dihydroxynaphthalene-type epoxy resins, polyhydroxybinaphthyl-type epoxy resins, naphthol-type epoxy resins, and binaphthol-type epoxy resins. Epoxy resins, including naphthylene ether type epoxy resins, naphthol phenolic varnish type epoxy resins, and naphthalene-type epoxy resins obtained through the condensation reaction of polyhydroxynaphthalene with aldehydes (epoxy resins containing a naphthalene skeleton); bixylenol type epoxy resins; dicyclopentadiene type epoxy resins; triphenol type epoxy resins; tert-butylcatechol type epoxy resins; anthracene type epoxy resins; glycidylamine type epoxy resins; and glycidyl ester type epoxy resins. Epoxy resins include: esters; biphenyl-type epoxy resins; linear aliphatic epoxy resins; epoxy resins with butadiene structures; alicyclic epoxy resins; heterocyclic epoxy resins; spirocyclic epoxy resins; cyclohexanediethanol-type epoxy resins; tris(hydroxymethyl)-type epoxy resins; tetraphenylethane-type epoxy resins; (meth)acrylate polyglycidyl acrylate, copolymers of glycidyl methacrylate and acrylates, and other acrylic resins containing glycidyl groups; fluorene-type epoxy resins; halogenated epoxy resins, etc.

[0045] From the viewpoint of reducing the average coefficient of linear thermal expansion, epoxy compounds are preferably copolymers containing epoxy groups or epoxy resins containing an aromatic backbone. Here, the aromatic backbone includes both polycyclic aromatic hydrocarbons and aromatic heterocycles. Preferred epoxy compounds include epoxy resins containing a naphthalene backbone; epoxy resins containing a fused-ring backbone; biphenyl-type epoxy resins; bisphenol-type epoxy resins such as bisphenol F and bisphenol A; cresol-phenolic varnish-type epoxy resins; and glycidyl ester-type epoxy resins.

[0046] Epoxy-containing copolymers can be obtained by polymerizing an epoxy-containing monomer and any monomers used as needed. Examples of epoxy-containing monomers include glycidyl methacrylate, 3,4-epoxybutyl methacrylate, 2-methyl-3,4-epoxycyclohexyl methacrylate, allyl glycidyl ether, and other epoxy-containing (meth)acrylate monomers, with glycidyl methacrylate being preferred. One epoxy-containing monomer can be used alone, or two or more can be used in combination.

[0047] Examples of any monomer include: styrene, (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, hexadecyl (meth)acrylate, octadecyl (meth)acrylate, dodecyl (meth)acrylate, dodecyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, benzyl (meth)acrylate, acrylamide, N,N-dimethyl(meth)acrylamide, (methyl) Acrylonitrile, 3-(meth)acryloylpropyltrimethoxysilane, N,N-dimethylaminoethyl methacrylate, glycidyl methacrylate, styrene, α-methylstyrene, p-methylstyrene, p-methoxystyrene, 2-hydroxyethyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxybutyl methacrylate, 1,4-cyclohexanediol mono(meth)acrylate, glyceryl mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, 2-hydroxy-3-phenoxypropyl methacrylate, 2-(meth)acryloyloxyethyl-2-hydroxyethyl phthalate, lactone-modified (meth)acrylate with hydroxyl groups at the end, 1-adamantyl methacrylate, etc., preferably n-butyl methacrylate. Any monomer can be used alone or in combination with two or more. "(Meth)acrylic acid" refers to acrylic acid and methacrylic acid. "(Meth)acrylate" refers to acrylates and methacrylates.

[0048] As epoxy resins containing a naphthalene skeleton, dihydroxynaphthalene-type epoxy resins, polyhydroxynaphthalene-type epoxy resins, and naphthalene-type epoxy resins obtained by the condensation reaction of polyhydroxynaphthalene with aldehydes are preferred. Examples of dihydroxynaphthalene-type epoxy resins include: 1,3-diepoxypropoxynaphthalene, 1,4-diepoxypropoxynaphthalene, 1,5-diepoxypropoxynaphthalene, 1,6-diepoxypropoxynaphthalene, 2,3-diepoxypropoxynaphthalene, 2,6-diepoxypropoxynaphthalene, and 2,7-diepoxypropoxynaphthalene. Examples of polyhydroxynaphthalene-type epoxy resins include: 1,1'-bi(2-epoxypropoxy)naphthalene, 1-(2,7-diepoxypropoxy)-1'-(2'-epoxypropoxy)naphthalene, and 1,1'-bi(2,7-diepoxypropoxy)naphthalene. Examples of naphthalene-type epoxy resins obtained by the condensation reaction of polyhydroxynaphthalene with aldehydes include 1,1'-bis(2,7-diepoxypropoxynaphthyl)methane, 1-(2,7-diepoxypropoxynaphthyl)-1'-(2'-epoxypropoxynaphthyl)methane, and 1,1'-bis(2-epoxypropoxynaphthyl)methane.

[0049] Examples of unsaturated carboxylic acids include acrylic acid, methacrylic acid, cinnamic acid, and butenoic acid. These carboxylic acids can be used alone or in combination of two or more. From the viewpoint of improving the photocurability of the photosensitive resin composition, acrylic acid and methacrylic acid are preferred. It should be noted that in this specification, the epoxy ester resin described above as a reaction product of an epoxy compound and (meth)acrylic acid is sometimes referred to as "epoxy (meth)acrylate," where the epoxy groups of the epoxy compound are substantially eliminated through the reaction with (meth)acrylic acid.

[0050] Examples of acid anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, and benzophenone tetracarboxylic dianhydride. These anhydrides can be used alone or in combination of two or more. From the perspective of improving the resolution and insulation reliability of the cured product, succinic anhydride and tetrahydrophthalic anhydride are preferred.

[0051] When obtaining acid-modified unsaturated epoxy ester resin, catalysts, solvents, and polymerization inhibitors can be used as needed.

[0052] As an acid-modified unsaturated epoxy ester resin, an acid-modified epoxy (meth)acrylate is preferred, and more preferably, either an acid-modified epoxy (meth)acrylate containing a naphthalene backbone or an acid-modified epoxy (meth)acrylate containing a bisphenol backbone. In the acid-modified unsaturated epoxy ester resin, "epoxy" refers to a structure derived from the aforementioned epoxy compound. For example, "bisphenol-type acid-modified epoxy (meth)acrylate" refers to an acid-modified unsaturated epoxy ester resin obtained by using a bisphenol-type epoxy resin as the epoxy compound and (meth)acrylate as the unsaturated carboxylic acid.

[0053] The acid-modified unsaturated epoxy ester resin is preferably a (meth)acrylic polymer with a glass transition temperature below -20°C. A (meth)acrylic polymer refers to a polymer containing structural units having a structure formed by polymerizing (meth)acrylic monomers. Examples of such (meth)acrylic polymers include polymers formed by polymerizing (meth)acrylic monomers, or polymers formed by copolymerizing (meth)acrylic monomers and monomers that can copolymerize with those (meth)acrylic monomers.

[0054] Examples of (meth)acrylic acid polymers with a glass transition temperature below -20°C include acid-modified unsaturated epoxy (meth)acrylic acid copolymers obtained by reacting (meth)acrylic acid with an epoxy-containing copolymer and then with an acid anhydride. Specifically, unsaturated epoxy (meth)acrylic acid copolymers are obtained by reacting (meth)acrylic acid with an epoxy-containing copolymer, and acid-modified unsaturated epoxy (meth)acrylic acid copolymers are obtained by reacting the unsaturated epoxy (meth)acrylic acid copolymer with an acid anhydride.

[0055] The preferred form of (meth)acrylic acid polymers with a glass transition temperature below -20°C is a compound obtained by reacting an epoxy-containing copolymer obtained by polymerizing an epoxy-containing monomer and any monomer, (meth)acrylic acid, and an acid anhydride, wherein the epoxy-containing monomer is glycidyl methacrylate, the arbitrary monomer is butyl acrylate, and the acid anhydride is tetrahydrophthalic anhydride.

[0056] Such acid-modified unsaturated epoxy ester resins can be commercially available. Specific examples include: "ZAR-2000" (a reaction product of bisphenol A type epoxy resin, acrylic acid, and succinic anhydride), "ZFR-1491H," and "ZFR-1533H" (a reaction product of bisphenol F type epoxy resin, acrylic acid, and tetrahydrophthalic anhydride (an acid-modified epoxy acrylate containing a bisphenol F type backbone)) manufactured by Nippon Kayaku Co., Ltd., and "PR-300CP" (a reaction product of cresol phenolic varnish type epoxy resin, acrylic acid, and acid anhydride) manufactured by Showa Denko Co., Ltd. These resins can be used alone or in combination of two or more.

[0057] Another form of resin containing olefinic unsaturated groups and carboxyl groups can be exemplified by unsaturated modified (meth)acrylic resins obtained by reacting an epoxy compound containing olefinic unsaturated groups with a (meth)acrylic resin having structural units obtained by polymerizing (meth)acrylic acid. Examples of epoxy compounds containing olefinic unsaturated groups include glycidyl methacrylate, 4-hydroxybutyl methacrylate glycidyl ether, and 3,4-epoxycyclohexylmethyl methacrylate. Furthermore, an anhydride can be reacted with the hydroxyl groups generated when the unsaturated groups are introduced. The same compounds as those described above can be used as the anhydride, and the preferred range is also the same.

[0058] Such unsaturated modified (meth)acrylic resins can be commercially available. Specific examples include: "SPC-1000" and "SPC-3000" manufactured by Showa Denko Corporation, and "CYCLOMER P(ACA)Z-250", "CYCLOMER P(ACA)Z-251", "CYCLOMER P(ACA)Z-254", "CYCLOMER P(ACA)Z-300", and "CYCLOMER P(ACA)Z-320" manufactured by Daicel-Allnex Corporation.

[0059] From the viewpoint of film-forming properties, the weight-average molecular weight of component (A) is preferably 1000 or more, more preferably 1500 or more, and even more preferably 2000 or more. As an upper limit, from the viewpoint of developability, it is preferably 10000 or less, more preferably 8000 or less, and even more preferably 7500 or less. The weight-average molecular weight is the weight-average molecular weight converted from polystyrene as determined by gel permeation chromatography (GPC).

[0060] Regarding the acid value of component (A), from the viewpoint of improving the alkaline developability of the photosensitive resin composition, an acid value of 0.1 mg KOH / g or higher is preferred, more preferably 0.5 mg KOH / g or higher, and even more preferably 1 mg KOH / g or higher. On the other hand, from the viewpoint of suppressing the washing away of fine patterns in the cured product due to development and improving insulation reliability, an acid value of 150 mg KOH / g or lower is preferred, more preferably 120 mg KOH / g or lower, and even more preferably 100 mg KOH / g or lower. Here, the acid value refers to the residual acid value of the carboxyl groups present in component (A), and the acid value can be determined by the following method. First, after accurately weighing about 1 g of the test resin solution, 30 g of acetone is added to the resin solution to dissolve it uniformly. Next, an appropriate amount of phenolphthalein as an indicator is added to the solution, and titration is performed with a 0.1 N KOH aqueous solution. Then, the acid value is calculated using the following formula.

[0061] Formula: A(b)=10×Vf×56.1 / (Wp×I)

[0062] It should be noted that in the above formula, A(b) represents the acid value (mgKOH / g), Vf represents the titration amount of KOH (mL), Wp represents the mass of the resin solution to be determined (g), and I represents the proportion of non-volatile components in the resin solution to be determined (mass%).

[0063] (A) In the manufacture of the component, from the viewpoint of improving storage stability, the ratio of "the number of moles of epoxy groups in the epoxy resin" to "the total number of moles of carboxyl groups in the unsaturated carboxylic acid and anhydride" is preferably in the range of 1:0.8 to 1.3, and more preferably in the range of 1:0.9 to 1.2.

[0064] From the viewpoint of improving flexibility, the glass transition temperature (Tg) of component (A) is preferably -300°C or higher, more preferably -200°C or higher, even more preferably -80°C or higher, preferably -20°C or lower, more preferably -23°C or lower, and even more preferably -25°C or lower. Here, the glass transition temperature of component (A) refers to the theoretical glass transition temperature of the main chain of component (A), which can be calculated using the FOX formula shown below. The glass transition temperature obtained by the FOX formula is essentially consistent with the glass transition temperature measured by differential scanning calorimetry (TMA, DSC, DTA), so the glass transition temperature of the main chain of component (A) can also be determined by differential scanning calorimetry; 1 / Tg=(W1 / Tg1)+(W2 / Tg2)+…+(Wm / Tgm)

[0065] W1 + W2 + ... + Wm = 1

[0066] Wm represents the content (mass%) of each monomer constituting component (A), and Tgm represents the glass transition temperature (K) of each monomer constituting component (A).

[0067] From the viewpoint of improving alkaline developability, when the non-volatile component in the photosensitive resin composition is set to 100% by mass, the content of component (A) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more. From the viewpoint of improving heat resistance and average coefficient of linear expansion, the upper limit is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 35% by mass or less, 30% by mass or less, or 25% by mass or less. It should be noted that, unless otherwise specified, the content of each component in the photosensitive resin composition in this invention refers to the value when the non-volatile component in the photosensitive resin composition is set to 100% by mass.

[0068] <(B) Photopolymerization Initiator>

[0069] The photosensitive resin composition includes a photopolymerization initiator as component (B). By including the photopolymerization initiator (B) in the photosensitive resin composition, the photosensitive resin composition can be effectively photocured.

[0070] (B) The photopolymerization initiator can be any compound, including, for example: acylphosphine oxide photoinitiators such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide; oxime ester photoinitiators such as 1-[4-(phenylthio)-1,2-octanedione 2-(O-benzoyl oxime) and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-acetone 1-(O-acetyl oxime); 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-1-butanone, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-[4-(4-morpholinyl)phenyl]-1-butanone, and 2-methyl-1-[4-(methylthio)]-[[4-methylphenyl]-[[4-(4-morpholinyl)phenyl]-1-butanone]-[[4-(methylthio]-[[4-methylphenyl ... α-aminoalkylbenzene ketone photopolymerization initiators such as [phenyl]-2-morpholino-1-propanone; benzophenone, methyl benzophenone, o-benzoylbenzoic acid, benzoyl ethyl ether, 2,2-diethoxyacetophenone, 2,4-diethylthioxanthraphenone, diphenyl-(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl 2,4,6-trimethylbenzoyl)phenylphosphine acid, 4,4'-bis(diethylamino)benzophenone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; sulfonium salt photopolymerization initiators, etc. These photopolymerization initiators can be used alone or in combination of two or more. From the viewpoint of enabling more effective photocuring of the photosensitive resin composition, either an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator is preferred, and an oxime ester photopolymerization initiator is more preferred. These photopolymerization initiators can be used alone or in combination of two or more.

[0071] Specific examples of photopolymerization initiators (B) include "Omnirad 907", "Omnirad 369", "Omnirad 379", "Omnirad 819" and "Omnirad TPO" manufactured by IGM Corporation; "Irgacure OXE-01", "Irgacure OXE-02", "Irgacure TPO" and "Irgacure 819" manufactured by BASF Corporation; and "N-1919" manufactured by ADEKA Corporation.

[0072] Furthermore, the photosensitive resin composition may also be combined with (B) a photopolymerization initiator to serve as a photopolymerization initiation aid, including tertiary amines such as ethyl N,N-dimethylaminobenzoate, isoamyl N,N-dimethylaminobenzoate, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine, and may also include photosensitizers such as pyrazolines, anthracene derivatives, coumarins, xanthones, and thioxanthones. These compounds may be used individually or in combination of two or more.

[0073] As for the content of the photopolymerization initiator (B), when the non-volatile component of the photosensitive resin composition is set to 100% by mass, from the viewpoint of ensuring sufficient photocuring of the photosensitive resin composition and improving insulation reliability, it is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, and even more preferably 0.01% by mass or more. On the other hand, from the viewpoint of suppressing the decrease in resolution due to oversensitivity, the upper limit is preferably 3% by mass or less, more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. It should be noted that when the photosensitive resin composition contains a photopolymerization initiation aid, it is preferable that the total content of (B) the photopolymerization initiator and the photopolymerization initiation aid is within the above-mentioned range.

[0074] <(C) Epoxy Resin>

[0075] In the photosensitive resin composition, epoxy resin is included as component (C). The inclusion of component (C) improves insulation reliability. However, component (C) as described herein does not include epoxy resins containing olefinic unsaturated groups and carboxyl groups.

[0076] Examples of components (C) include: xylenol-type epoxy resin, bisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenol S-type epoxy resin, bisphenol AF-type epoxy resin, dicyclopentadiene-type epoxy resin, triphenol-type epoxy resin, naphthol phenolic varnish-type epoxy resin, phenol phenolic varnish-type epoxy resin, tert-butylcatechol-type epoxy resin, naphthalene-type epoxy resin, naphthol-type epoxy resin, anthracene-type epoxy resin, glycidylamine-type epoxy resin, glycidyl ester-type epoxy resin, cresol phenolic varnish-type epoxy resin, biphenyl-type epoxy resin, linear aliphatic epoxy resin, epoxy resin with butadiene structure, alicyclic epoxy resin, heterocyclic epoxy resin, spirocyclic epoxy resin, cyclohexane-type epoxy resin, cyclohexanediol-type epoxy resin, naphthylene ether-type epoxy resin, tris(hydroxymethyl)-type epoxy resin, tetraphenylethane-type epoxy resin, etc. (C) One type of epoxy resin can be used alone, or two or more types can be used in combination.

[0077] In the photosensitive resin composition, epoxy resin having two or more epoxy groups per molecule is preferably included as component (C). From the viewpoint of significantly obtaining the desired effect of the present invention, the proportion of epoxy resin having two or more epoxy groups per molecule relative to 100% by mass of the non-volatile component of component (C) is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

[0078] Component (C) includes an epoxy resin that is liquid at 20°C (hereinafter sometimes referred to as "liquid epoxy resin") and an epoxy resin that is solid at 20°C (hereinafter sometimes referred to as "solid epoxy resin"). The resin composition may contain only liquid epoxy resin, only solid epoxy resin, or a combination of both.

[0079] As a solid epoxy resin, it is preferred to be a solid epoxy resin having three or more epoxy groups per molecule, and more preferably an aromatic solid epoxy resin having three or more epoxy groups per molecule.

[0080] As a solid epoxy resin, the preferred types are xylenol-type epoxy resin, naphthalene-type epoxy resin, naphthalene-type tetrafunctional epoxy resin, cresol-phenolic varnish-type epoxy resin, dicyclopentadiene-type epoxy resin, triphenol-type epoxy resin, naphthol-type epoxy resin, biphenyl-type epoxy resin, naphthylene ether-type epoxy resin, anthracene-type epoxy resin, bisphenol A-type epoxy resin, bisphenol AF-type epoxy resin, and tetraphenylethane-type epoxy resin, with naphthalene-type epoxy resin being more preferred.

[0081] Specific examples of solid epoxy resins include: DIC Corporation's "HP4032H" (naphthalene-type epoxy resin); DIC Corporation's "HP-4700" and "HP-4710" (naphthalene-type tetrafunctional epoxy resins); DIC Corporation's "N-690" (cresol phenolic varnish type epoxy resin); DIC Corporation's "N-695" (cresol phenolic varnish type epoxy resin); and DIC Corporation's "HP-7200," "HP-7200HH," and "HP-72..." 00H (dicyclopentadiene type epoxy resin); "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", and "HP6000" (naphthyl ether type epoxy resin) manufactured by DIC Corporation; "EPPN-502H" (triphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol phenolic varnish type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; and "NC3000H" manufactured by Nippon Kayaku Co., Ltd. "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin); "ESN475V" (naphthol type epoxy resin) manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.; "ESN485" (naphthol phenolic varnish type epoxy resin) manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd.; "YX4000H", "YX4000", "YL6121" (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YX4000HK" (bixylenol type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd. The following are epoxy resins manufactured by Mitsubishi Chemical Corporation: YX8800 (anthracene-type epoxy resin); PG-100 and CG-500 manufactured by Osaka Gas Chemical Co., Ltd.; YL7760 (bisphenol AF type epoxy resin); YL7800 (fluorene type epoxy resin); jER1010 (solid bisphenol A type epoxy resin); and jER1031S (tetrahydroxyphenyl ethane type epoxy resin). These can be used individually or in combination.

[0082] As a liquid epoxy resin, a liquid epoxy resin having two or more epoxy groups in one molecule is preferred.

[0083] The preferred liquid epoxy resins are bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin, phenolic varnish type epoxy resin, alicyclic epoxy resin with ester skeleton, cyclohexane type epoxy resin, cyclohexanediol type epoxy resin, glycidylamine type epoxy resin, and epoxy resin with butadiene structure, with bisphenol A type epoxy resin and bisphenol F type epoxy resin being more preferred.

[0084] Specific examples of liquid epoxy resins include: DIC Corporation's "HP4032", "HP4032D", and "HP4032SS" (naphthalene-type epoxy resin); Mitsubishi Chemical Corporation's "828US", "jER828EL", "825", and "EPIKOTE 828EL" (bisphenol A type epoxy resin); Mitsubishi Chemical Corporation's "jER807" and "1750" (bisphenol F type epoxy resin); Mitsubishi Chemical Corporation's "jER152" (phenolic varnish type epoxy resin); Mitsubishi Chemical Corporation's "630" and "630LSD" (glycidylamine type epoxy resin); Nippon Steel & Sumitomo Metal Chemicals Co., Ltd.'s "ZX1059" (a mixture of bisphenol A and bisphenol F type epoxy resins); Nagase... ChemteX Corporation's "EX-721" (glycidyl ester type epoxy resin); Daicel Corporation's "CELLOXIDE 2021P" (alicyclic epoxy resin with ester skeleton); Daicel Corporation's "PB-3600" (epoxy resin with butadiene structure); Nippon Steel & Sumitomo Chemical Co., Ltd.'s "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin), etc. These can be used individually or in combination of two or more.

[0085] As component (C), when liquid epoxy resin and solid epoxy resin are used in combination, their mass ratio (liquid epoxy resin: solid epoxy resin) is preferably 1:1 to 1:20, more preferably 1:1.5 to 1:15, and particularly preferably 1:2 to 1:10. By keeping the mass ratio of liquid epoxy resin to solid epoxy resin within the aforementioned range, the desired effects of the present invention can be significantly obtained.

[0086] (C) The epoxy equivalent of component (C) is preferably 50 g / eq. to 5000 g / eq., more preferably 50 g / eq. to 3000 g / eq., even more preferably 80 g / eq. to 2000 g / eq., and still more preferably 110 g / eq. to 1000 g / eq. By ensuring that the epoxy equivalent is within this range, the crosslinking density of the cured resin composition layer becomes sufficient, resulting in an insulating layer with low surface roughness. The epoxy equivalent is the mass of epoxy resin containing 1 equivalent of epoxy groups. This epoxy equivalent can be determined according to JIS K7236.

[0087] From the viewpoint of significantly achieving the desired effects of the present invention, the weight-average molecular weight (Mw) of component (C) is preferably 100 to 5000, more preferably 250 to 3000, and even more preferably 400 to 1500. The weight-average molecular weight of the resin can be determined by gel permeation chromatography (GPC) as a value converted from polystyrene.

[0088] From the viewpoint of obtaining an insulating layer exhibiting good tensile mechanical strength and insulation reliability, when the non-volatile component in the resin composition is set to 100% by mass, the content of component (C) is preferably 1% by mass or more, more preferably 2% by mass or more, and even more preferably 3% by mass or more. From the viewpoint of significantly obtaining the desired effects of the present invention, the upper limit of the content of component (C) is preferably 20% by mass or less, more preferably 15% by mass or less, and particularly preferably 12% by mass or less.

[0089] <(D) Volatile Components>

[0090] The photosensitive resin composition contains volatile components as component (D). By including component (D) in the photosensitive resin composition under conditions satisfying formulas (1) and (2), a cured product with excellent undercut resistance can be obtained. Furthermore, by including component (D) in the photosensitive resin composition, the viscosity of the varnish of the photosensitive resin composition can be adjusted.

[0091] As a volatile component (D), solvents such as organic solvents can be listed. Organic solvents also include organic solvents in organic solvent solutions containing components (A) to (C), (E), or (G) when making photosensitive resin compositions.

[0092] Examples of such solvents include: ketones such as methyl ethyl ketone and cyclohexanone; aromatics such as toluene, xylene, and tetramethylbenzene; glycol ethers such as methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate, carbitol acetate, and diethylene glycol monoethyl ether acetate; aliphatic hydrocarbons such as octane and decane; and petroleum solvents such as petroleum ether, naphtha, hydrogenated naphtha, and solvent naphtha. These solvents may be a single type or a combination of two or more. From the viewpoint of obtaining a cured product with excellent undercut resistance, it is preferable to have either a ketone or a glycol ether as the solvent.

[0093] From the viewpoint of obtaining a cured product with excellent undercut resistance, (D) the volatile components are preferably a mixture of a high-boiling-point organic solvent and a low-boiling-point organic solvent. As for the high-boiling-point organic solvent, the boiling point is preferably 100°C or higher, more preferably 120°C or higher, and even more preferably 150°C or higher; the upper limit is not particularly limited and can be set to 300°C or lower, etc. As for the low-boiling-point organic solvent, the boiling point is preferably below 100°C, more preferably below 90°C, and even more preferably below 85°C; the lower limit is not particularly limited and can be set to 30°C or higher, etc.

[0094] The content of volatile components (D) can be adjusted according to the conditions that satisfy equations (1) and (2).

[0095] <(E) Reactive Diluent>

[0096] In addition to the components mentioned above, the photosensitive resin composition may, as an optional component, also include a reactive diluent as component (E). However, component (E) does not include component (A). By including the reactive diluent (E) in the photosensitive resin composition, photoreactivity can be improved. As component (E), a photosensitive (meth)acrylate compound having one or more (meth)acryloyl groups in one molecule, which is liquid, solid, or semi-solid at room temperature, can be used. Room temperature refers to approximately 25°C.

[0097] Examples of photosensitive (meth)acrylate compounds include: hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxybutyl acrylate; mono- or diacrylates of diols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, and propylene glycol; acrylamides such as N,N-dimethylacrylamide and N-hydroxymethylacrylamide; aminoalkyl acrylates such as N,N-dimethylaminoethyl acrylate; polyacrylates of polyols such as trimethylolpropane, pentaerythritol, and dipentaerythritol, or their adducts of ethylene oxide, propylene oxide, or ε-caprolactone; acrylates of phenols such as phenoxyacrylate and phenoxyethyl acrylate, or their adducts of ethylene oxide or propylene oxide; epoxy acrylates derived from glycidyl ethers such as trimethylolpropane triglycidyl ether; modified epoxy acrylates; melamine acrylates; and / or methacrylates corresponding to the aforementioned acrylic acids. Preferably, the esters are polyacrylates or polymethacrylates, and examples include: trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane EO addition tri(meth)acrylate, glycerol PO addition tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tetrafurfuryl alcohol oligo(meth)acrylate, ethyl carbitol oligo(meth)acrylate, 1,4-butanediol oligo(meth)acrylate, 1,6-hexanediol oligo(meth)acrylate, trimethylolpropane oligo(meth)acrylate, pentaerythritol oligo(meth)acrylate, tetramethylolmethane tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate. N,N,N',N'-tetra(β-hydroxyethyl)ethylenediamine (meth)acrylates, etc., as ternary or higher-order acrylates or methacrylates, can be listed as follows: tris(2-(meth)acryloyloxyethyl) phosphate, tris(2-(meth)acryloyloxypropyl) phosphate, tris(3-(meth)acryloyloxypropyl) phosphate, tris(3-(meth)acryloyl-2-hydroxyoxypropyl) phosphate, di(3-(meth)acryloyl-2-hydroxyoxypropyl)(2-(meth)acryloyloxyethyl) phosphate, (3-(meth)acryloyl-2-hydroxyoxypropyl)di(2-(meth)acryloyloxyethyl) phosphate, etc., phosphate triesters (meth)acrylates, etc. These photosensitive (meth)acrylate compounds can be used alone or in combination of two or more. "EO" refers to ethylene oxide.

[0098] (E) Commercially available reactive diluents may be used. Examples of commercially available diluents include "DPHA" manufactured by Nippon Kayaku Co., Ltd., and "EBECRYL 3708" manufactured by Daicel-Zhenxin Co., Ltd.

[0099] From the viewpoint of promoting photocuring, the content of the reactive diluent (E) is preferably 1% or more, more preferably 2% or more, and even more preferably 3% or more, preferably 25% or less, more preferably 20% or less, and even more preferably 15% or less, when the total solid content of the photosensitive resin composition is set to 100% by mass.

[0100] <(F) Inorganic filler materials>

[0101] In addition to the above-mentioned components, the photosensitive resin composition may also contain inorganic filler material as component (F) as an optional component.

[0102] Inorganic compounds are used as the inorganic filler material in (F). Examples of inorganic filler materials include: silicon dioxide, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconium phosphate, and zirconium phosphotungstenate, etc. Among these, silicon dioxide and magnesium hydroxide are preferred, and silicon dioxide is particularly preferred. Examples of silicon dioxide include amorphous silicon dioxide, fused silicon dioxide, crystalline silicon dioxide, synthetic silicon dioxide, and hollow silicon dioxide, etc. Furthermore, spherical silicon dioxide is preferred. (F) One type of inorganic filler material may be used alone, or two or more types may be used in combination.

[0103] Commercially available products that are components (F) include, for example: "UFP-20" and "UFP-30" manufactured by DENKA Corporation; "SP60-05" and "SP507-05" manufactured by Nippon Steel & Sumitomo Metal Materials Co., Ltd.; "SC2050", "YC100C", "YA050C", "YA050C-MJE", "YA010C", "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" manufactured by Admatechs Co., Ltd.; "SILFIL NSS-3N", "SILFIL NSS-4N", and "SILFIL NSS-5N" manufactured by Tokuyama Co., Ltd.; and "EP4-A" manufactured by Kamishima Chemical Co., Ltd.

[0104] The specific surface area of ​​component (F) is preferably 1 m². 2 / g or more, preferably 2m 2 / g or more, especially preferably 3m 2 / g or more. There is no particular limit to the upper limit, but 60m is preferred. 2 / g or less, 50m 2 / g or less or 40m 2 / g or less. The specific surface area can be obtained by using a specific surface area measuring device (Macsorb HM-1210 manufactured by MOUNTECH Corporation) to adsorb nitrogen onto the sample surface and then calculating the specific surface area using the BET multi-point method.

[0105] From the viewpoint of significantly achieving the desired effect of the present invention, the average particle size of component (F) is preferably 0.01 μm or more, more preferably 0.05 μm or more, particularly preferably 0.1 μm or more, preferably 5 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less.

[0106] The average particle size of component (F) can be determined by laser diffraction scattering based on the Mie scattering theory. Specifically, a laser diffraction particle size distribution measuring device can be used to prepare the particle size distribution of the inorganic filler material on a volume basis, and the median particle size can be used as the average particle size for measurement. The sample for testing can be obtained by weighing 100 mg of inorganic filler material and 10 g of methyl ethyl ketone into a tube and dispersing it ultrasonically for 10 minutes. For the sample for testing, a laser diffraction particle size distribution measuring device can be used, with the light source wavelength set to blue and red, to measure the volume-based particle size distribution of component (F) in a flow cell mode, and the average particle size can be calculated based on the obtained particle size distribution as the median particle size. Examples of laser diffraction particle size distribution measuring devices include the "LA-960" manufactured by Horiba Manufacturing Co., Ltd.

[0107] From the viewpoint of improving moisture resistance and dispersibility, component (F) is preferably treated with a surface treatment agent. Examples of surface treatment agents include vinyl silane coupling agents, (meth)acrylic acid coupling agents, fluorinated silane coupling agents, aminosilane coupling agents, epoxy silane coupling agents, mercaptosilane coupling agents, silane coupling agents, alkoxysilanes, organosilazane compounds, and titanate coupling agents. Among these, from the viewpoint of significantly achieving the effects of the present invention, vinyl silane coupling agents, (meth)acrylic acid coupling agents, and aminosilane coupling agents are preferred. Furthermore, a single surface treatment agent may be used, or two or more may be used in any combination.

[0108] Commercially available surface treatment agents include, for example: KBM1003 (vinyltriethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd.; KBM503 (3-methacryloyloxypropyltriethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd.; KBM403 (3-epoxypropoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd.; KBM803 (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd.; and KBE903 (3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Industry Co., Ltd. Products manufactured by Shin-Etsu Chemical Co., Ltd. include: N-phenyl-3-aminopropyltrimethoxysilane, SZ-31 (hexamethyldisilazane), KBM103 (phenyltrimethoxysilane), KBM-4803 (long-chain epoxy silane coupling agent), and KBM-7103 (3,3,3-trifluoropropyltrimethoxysilane).

[0109] From the viewpoint of improving the dispersibility of inorganic filler materials, the degree of surface treatment by surface treatment agent is preferably controlled within a specified range. Specifically, 100 parts by weight of inorganic filler material is preferably surface treated with 0.2 parts by weight to 5 parts by weight of surface treatment agent, more preferably with 0.2 parts by weight to 3 parts by weight of surface treatment agent, and even more preferably with 0.3 parts by weight to 2 parts by weight of surface treatment agent.

[0110] The degree of surface treatment by the surface treatment agent can be evaluated by the carbon content per unit surface area of ​​the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the carbon content per unit surface area of ​​the inorganic filler is preferably 0.02 mg / m². 2 The above, more preferably 0.1 mg / m 2 The above is further preferred to be 0.2 mg / m³. 2 That's all. On the other hand, from the viewpoint of suppressing the increase in melt viscosity of the resin varnish and melt viscosity in sheet form, 1 mg / m³ is preferred. 2 The following is more preferably 0.8 mg / m³ 2 The following is a further preferred value: 0.5 mg / m³ 2 the following.

[0111] The carbon content per unit surface area of ​​inorganic filler materials can be determined after cleaning the surface-treated inorganic filler material with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, sufficient MEK is added as a solvent to the surface-treated inorganic filler material, and the mixture is ultrasonically cleaned at 25°C for 5 minutes. After removing the supernatant and drying the solid components, the carbon content per unit surface area of ​​the inorganic filler material can be determined using a carbon analyzer. A suitable carbon analyzer is the "EMIA-320V" manufactured by Horiba Corporation.

[0112] From the viewpoint of achieving significant effects of the present invention, when the non-volatile component in the photosensitive resin composition is set to 100% by mass, the content of component (F) is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less.

[0113] <(G) Other Additives>

[0114] The photosensitive resin composition may further contain (G) other additives to a degree that does not impair the purpose of the present invention. As (G) other additives, various additives may be added, such as: thermoplastic resins, organic fillers, melamine, organobentonite particles, phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium dioxide, carbon black, naphthalene black, etc.; polymerization inhibitors such as hydroquinone, phenothiazine, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol, etc.; thickeners such as bentonite, montmorillonite, etc.; defoamers of organosilicon, fluorine, and vinyl resins; brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, phosphorus compounds, aromatic condensed phosphates, halogenated condensed phosphates, etc.; flame retardants; phenolic curing agents; cyanate ester curing agents; and thermosetting resins.

[0115] The photosensitive resin composition can be prepared by mixing the above-mentioned components (A) to (D) as essential components, appropriately mixing the above-mentioned components (E) to (G) as optional components, and mixing or stirring with a mixing (blending) device such as a three-roll mill, ball mill, bead mill, sand mill, or a stirring device such as a super mixer or planetary mixer as needed.

[0116] <Properties and Uses of Photosensitive Resin Compositions>

[0117] The weight loss rate (%) of the photosensitive resin composition after drying at 130°C for 15 minutes is defined as a. Furthermore, the weight loss rate (%) of the photosensitive resin composition after drying at 180°C for 15 minutes is defined as b. At this time, by satisfying the relationship between equations (1) and (2), a cured product with excellent undercut resistance can be obtained, thereby improving resolution. The photosensitive resin composition, as a layered photosensitive resin composition layer, only needs to satisfy the relationship between equations (1) and (2) during the exposure process. For example, a photosensitive resin composition layer formed on a support, or a photosensitive resin composition layer formed by directly coating and drying the photosensitive resin composition on a circuit board, etc., can be cited.

[0118] V = a 2 +b 2 Where V≤30 (1)

[0119] a / b≤0.6 (2).

[0120] The weight loss rate 'a' (%) referred to here is the value calculated according to formula (A) after the photosensitive film with the support, after being coated with resin varnish and dried, is cut into 10cm × 10cm pieces, placed in a desiccator for 30 minutes, and then the mass (g) of the photosensitive film with the support is defined as (a1). Then, the mass (g) of the photosensitive film with the support is defined as (a2) after being heated in an oven at 130°C for 15 minutes. Similarly, the weight loss rate 'b' (%) referred to here is the value calculated according to formula (B) after the photosensitive film with the support, after being coated with resin varnish and dried, is cut into 10cm × 10cm pieces, placed in a desiccator for 30 minutes, and then the mass (g) of the photosensitive film with the support is defined as (b1). Then, the mass (g) of the photosensitive film with the support is defined as (b2) after being heated in an oven at 180°C for 15 minutes. It should be noted that "mass (g) of the support body" in formulas (A) and (B) refers to the mass (g) of the support body after it has been cut into 10cm×10cm pieces and placed in a desiccator for 30 minutes.

[0121] [Mathematical Expression 1]

[0122] .

[0123] From the viewpoint of obtaining a cured product with excellent undercut resistance and improved resolution, V in formula (1) is 30 or less, preferably 28 or less, more preferably 27 or less, and even more preferably 26 or less. From the viewpoint of significantly obtaining the effects of the present invention, the lower limit of V in formula (1) is preferably 1 or more, more preferably 3 or more, and even more preferably 5 or more.

[0124] From the viewpoint of obtaining a cured product with excellent undercut resistance and improved resolution, a / b in formula (2) is 0.6 or less, preferably 0.55 or less, more preferably 0.5 or less, and even more preferably 0.48 or less. From the viewpoint of significantly obtaining the effects of the present invention, the lower limit of a / b in formula (2) is preferably 0.01 or more, more preferably 0.05 or more, and even more preferably 0.1 or more.

[0125] The photosensitive resin composition of the present invention exhibits excellent resolution properties in cured products obtained by photocuring the photosensitive resin composition of the present invention. Therefore, no residue is found at the bottom of a circular hole (through hole) with an opening diameter of 100 μm. The evaluation of residue at the bottom of the through hole can be performed according to the method described later in <Evaluation of Residue at the Bottom of Through Hole and Undercut Resistance>.

[0126] The cured product obtained by photocuring the photosensitive resin composition of the present invention exhibits excellent undercut resistance. This provides an insulating layer and a solder resist layer with excellent undercut resistance. The undercut is preferably 5 μm or less, more preferably 4 μm or less, and even more preferably 3 μm or less. The lower limit is not particularly limited and can be set to 0.1 μm or more, etc. Regarding the undercut, it can be measured according to the method described in "Evaluation of Residue at the Bottom of Through-hole and Undercut Resistance" described later.

[0127] The photosensitive resin composition of the present invention exhibits excellent embedding properties. A specific example of embedding property measurement is to laminate a photosensitive film onto an inner circuit board (conductor thickness 18 μm, thickness 0.8 mm). The presence or absence of pores is observed by visually inspecting the appearance of the inner circuit board with the laminated photosensitive film. In this case, the number of pores is typically 0. Detailed evaluation of embedding property can be performed according to the methods described in the examples below.

[0128] The photosensitive resin composition of the present invention exhibits a low melt viscosity. Preferably, the melt viscosity is 100 poise or more, more preferably 500 poise or more, even more preferably 1000 poise or more, more preferably 20,000 poise or less, more preferably 15,000 poise or less, and even more preferably 10,000 poise or less. The melt viscosity can be measured according to the method described in the examples below.

[0129] The photosensitive resin composition of the present invention has no particular limitation on its application and can be widely used in photosensitive films, photosensitive films with supports, insulating resin sheets such as prepregs, circuit boards (for laminates, multilayer printed wiring boards, etc.), solder resist layers (solder resist), underfill materials, chip bonding materials, semiconductor sealing materials, through-hole filling resins, component embedding resins, and other applications requiring photosensitive resin compositions. Suitable applications include: photosensitive resin compositions for insulating layers of printed wiring boards (printed wiring boards where the cured product of the photosensitive resin composition serves as the insulating layer), photosensitive resin compositions for interlayer insulating layers (printed wiring boards where the cured product of the photosensitive resin composition serves as the interlayer insulating layer), photosensitive resin compositions for plating formation (printed wiring boards where a plating layer is formed on the cured product of the photosensitive resin composition), and photosensitive resin compositions for solder resist layers (printed wiring boards where the cured product of the photosensitive resin composition serves as the solder resist layer).

[0130] [Photosensitive film]

[0131] Regarding the photosensitive resin composition of the present invention, a photosensitive film can be formed by coating a resin varnish containing the photosensitive resin composition onto a support substrate and allowing it to dry. Alternatively, a photosensitive film can be formed by coating the resin varnish onto a support and allowing it to dry. In other words, the photosensitive film of the present invention contains the photosensitive resin composition of the present invention. Examples of support substrates include glass epoxy resin substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates.

[0132] Examples of coating methods for resin varnishes include: gravure coating, micro-gravure coating, reverse coating, kiss reverse coating, die coating, slot die coating, lip coating, comma coating, blade coating, roller coating, knife coating, curtain coating, chamber gravure coating, slot orifice coating, spraying, and dip coating.

[0133] Resin varnish can be applied in multiple coats, in a single coat, or in a combination of different methods. Among these, the orifice coating method, which provides excellent coating uniformity, is preferred. Furthermore, to avoid contamination by foreign matter, the coating process is preferably performed in an environment with minimal foreign matter generation, such as a cleanroom.

[0134] Regarding photosensitive films, they can be manufactured according to methods known to those skilled in the art, for example, by coating a photosensitive resin composition onto a support substrate or support body and drying the (D) component using heating or hot air blowing. The photosensitive resin composition can be manufactured, for example, using a resin varnish containing a non-volatile component of the photosensitive resin composition and an excess of the (D) component. Specifically, firstly, after completely removing bubbles from the resin varnish using a vacuum degassing method, the resin varnish is coated onto a support substrate, and the amount of the (D) component is adjusted by drying using a hot air furnace or a far-infrared furnace, thereby manufacturing a photosensitive film containing a photosensitive resin composition layer formed from the photosensitive resin composition. As one embodiment of the method for manufacturing a photosensitive film, it can be obtained by drying the resin varnish under conditions of a maximum temperature of 105°C or higher and 135°C or lower, and a drying time of 6 minutes or higher and 20 minutes or lower.

[0135] The drying temperature varies depending on the curability of the photosensitive resin composition and the amount of component (D) in the resin varnish, and can be carried out at 80°C to 120°C. However, from the viewpoint of obtaining a cured product with excellent undercut resistance, the maximum drying temperature is preferably 105°C or higher, more preferably 110°C or higher. The lower limit of the maximum temperature is not particularly limited, but is preferably 135°C or lower, more preferably 130°C or lower.

[0136] The drying time also varies depending on the curing properties of the photosensitive resin composition and the amount of component (D) in the resin varnish, and is preferably 6 minutes or more, preferably 30 minutes or less, and more preferably 20 minutes or less. Here, drying time refers to the time starting from when the drying temperature reaches 80°C.

[0137] The residual amount of component (D) in the photosensitive resin composition layer is preferably 5% by mass or less, more preferably 2% by mass or less, relative to the total amount of the photosensitive resin composition layer. Those skilled in the art can appropriately set suitable drying conditions through simple experiments.

[0138] In this invention, as the photosensitive resin composition layer, it is sufficient to satisfy formulas (1) and (2) during the exposure process to obtain a cured product with excellent undercut resistance and improve resolution. Therefore, the thickness of the photosensitive resin composition layer is not particularly limited. From the viewpoint of improving processability and suppressing the decrease in sensitivity and resolution (resolution) inside the photosensitive resin composition layer, it is preferably 5 μm or more, more preferably 10 μm or more, further preferably 15 μm or more, preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less.

[0139] [Photosensitive film with support]

[0140] The photosensitive resin composition of the present invention can be suitably used in the form of a photosensitive film with a support on which a photosensitive resin composition layer is formed. That is, the photosensitive film with a support includes a support and a photosensitive resin composition layer formed with the photosensitive resin composition of the present invention disposed on the support.

[0141] Examples of supports include polyethylene terephthalate films, polyethylene naphthalate films, polypropylene films, polyethylene films, polyvinyl alcohol films, triacetyl acetate films, etc., with polyethylene terephthalate films being particularly preferred.

[0142] Commercially available supports include, but are not limited to, products such as "ALPHAN MA-410" and "E-200C" manufactured by Oji Paper Co., Ltd., polypropylene films manufactured by Shin-Etsu Film Co., Ltd., and polyethylene terephthalate films such as "PS-25" manufactured by Teijin Co., Ltd. To facilitate removal from these supports, a release agent such as a silicone coating can be applied to the surface. The thickness of the support is preferably in the range of 5 μm to 50 μm, more preferably in the range of 10 μm to 25 μm. A thickness of 5 μm or more suppresses support breakage during peeling before development; a thickness of 50 μm or less improves the resolution during exposure from the support. Furthermore, a support with low white point (fish eye) is preferred. Here, white spots refer to defects formed when foreign matter, undissolved substances, oxidized deterioration products, etc., enter the membrane during the manufacturing process of a membrane by hot melting of materials and mixing, extrusion, biaxial stretching, casting, etc.

[0143] Furthermore, to reduce light scattering during exposure using active energy rays such as ultraviolet light, the support is preferably made of a material with excellent transparency. Specifically, the support is preferably made of a material with a turbidity (haze standardized in JIS K6714) of 0.1 to 5, which is an indicator of transparency. Furthermore, the photosensitive resin composition layer can also be protected with a protective film.

[0144] By protecting the photosensitive resin composition layer of the photosensitive film with the support with a protective film, it is possible to prevent debris or other contaminants from adhering to the surface of the photosensitive resin composition layer or causing damage. The protective film can be made of the same material as the support described above. The thickness of the protective film is not particularly limited, but is preferably in the range of 1 μm to 40 μm, more preferably in the range of 5 μm to 30 μm, and even more preferably in the range of 10 μm to 30 μm. A thickness of 1 μm or more improves the processability of the protective film; a thickness of 40 μm or less tends to improve economic efficiency (low cost). It should be noted that, for the protective film, it is preferable that the adhesion between the photosensitive resin composition layer and the protective film is smaller than the adhesion between the photosensitive resin composition layer and the support.

[0145] From the viewpoint of improving processability and suppressing the decrease in sensitivity and resolution within the photosensitive resin composition layer, the thickness of the photosensitive resin composition layer is preferably 10 μm or more, more preferably 15 μm or more, even more preferably 20 μm or more, preferably 30 μm or less, more preferably 28 μm or less, and even more preferably 25 μm or less.

[0146] Printed wiring board

[0147] The printed wiring board of the present invention comprises an insulating layer formed by curing the photosensitive resin composition of the present invention. This insulating layer is preferably used as a solder resist layer.

[0148] In detail, the printed wiring board of the present invention can be manufactured using the above-described photosensitive film or a photosensitive film with a support. Hereinafter, an example of a case where the insulating layer is a solder resist layer will be described.

[0149] <Coating and Drying Process>

[0150] When a resin varnish containing a photosensitive resin composition is directly applied to a circuit board, a photosensitive film is formed on the circuit board by drying and evaporating component (D).

[0151] Examples of circuit boards include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates. It should be noted that, in this context, "circuit board" refers to a substrate on one or both sides of a support substrate as described above, on which a patterned conductor layer (circuit) is formed. Furthermore, in multilayer printed wiring boards (PCBs) formed by alternating layers of conductor and insulating layers, the substrate on one or both sides of the outermost layer of the PCB is also included within the scope of the circuit board discussed here. It should be noted that the surface of the conductor layer may be pre-roughened through blackening treatment, copper etching, or similar processes.

[0152] As for the coating method, full-page printing based on screen printing is generally used, but any other means can be used as long as it can achieve uniform coating. For example, spray coating, hot melt coating, rod coating, squeegee coating, blade coating, air knife coating, curtain flow coating, roller coating, gravure coating, offset printing, dip coating, brush coating, and other common coating methods can all be used. After coating, drying is performed using a hot air oven or far-infrared oven as needed. The preferred drying conditions are 80℃~120℃ for 3 to 13 minutes. This process forms a photosensitive film on the circuit board.

[0153] <Lamination Process>

[0154] On the other hand, when using a photosensitive film with a support, the photosensitive resin composition layer is laminated to one or both sides of the circuit board using a vacuum laminator. During the lamination process, if the photosensitive film with the support has a protective film, after removing the protective film, the photosensitive film with the support and the circuit board are preheated as needed, and the photosensitive resin composition layer is pressed onto the circuit board while being heated. For photosensitive films with a support, a vacuum lamination method is preferably used to laminate them to the circuit board under reduced pressure.

[0155] There are no particular limitations on the conditions for the lamination process. For example, preferred conditions are: the pressing temperature (lamination temperature) is preferably set to 70℃~140℃, and the pressing pressure is preferably set to 1kgf / cm. 2 ~11kgf / cm 2 (9.8×10 4 N / m 2 ~107.9×10 4 N / m 2 The lamination time is preferably set to 5 to 300 seconds, and lamination is performed under reduced pressure of 20 mmHg (26.7 hPa) or less. Furthermore, the lamination process can be batch-type or continuous using rollers. Vacuum lamination can be performed using commercially available vacuum laminators. Examples of commercially available vacuum laminators include: vacuum dressing machines manufactured by Nikko-Materials Co., Ltd., vacuum pressure laminators manufactured by Meiki Manufacturing Co., Ltd., roller dry coating machines manufactured by Hitachi Industries Co., Ltd., and vacuum laminators manufactured by Hitachi AIC Co., Ltd.

[0156] <Exposure Process>

[0157] After a photosensitive resin composition layer is deposited on a circuit board through a coating and drying process or a lamination process, an exposure process is performed in which a predetermined portion of the photosensitive resin composition layer is irradiated with active light through a mask pattern, thereby photocuring the irradiated portion of the photosensitive resin composition layer. Examples of active light include ultraviolet light, visible light, electron beams, and X-rays, with ultraviolet light being particularly preferred. The irradiation dose of ultraviolet light is approximately 10 mJ / cm². 2 ~1000mJ / cm 2 Exposure methods include contact exposure, where the mask pattern is tightly adhered to the printed wiring board, and non-contact exposure, where parallel light is used for exposure in a loosely adhered state; either method can be used. Furthermore, if a support is present on the photosensitive resin composition layer, exposure can be performed from the support, or the support can be peeled off before exposure.

[0158] The solder mask layer uses the photosensitive resin composition of the present invention, thus exhibiting excellent resolution. Therefore, as the exposure pattern in the mask pattern, patterns with a circuit width (line width, L) to circuit spacing (line pitch, S) ratio (L / S) of 100 μm / 100 μm or less (i.e., wiring spacing 200 μm or less), L / S = 80 μm / 80 μm or less (wiring spacing 160 μm or less), L / S = 70 μm / 70 μm or less (wiring spacing 140 μm or less), and L / S = 60 μm / 60 μm or less (wiring spacing 120 μm or less) can be used. It should be noted that the spacing does not need to be uniform across the entire circuit board.

[0159] The solder mask layer uses the photosensitive resin composition of the present invention, thus exhibiting excellent undercut resistance. Therefore, the via diameter is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. The lower limit is not particularly limited and can be 1 μm or more, 10 μm or more, etc.

[0160] <Developing Process>

[0161] After the exposure process, if a support is present on the photosensitive resin composition layer, the uncured portion (unexposed portion) is removed by wet or dry development and then developed to form a pattern.

[0162] In the case of wet development described above, the developer can be a safe, stable, and easy-to-handle developer such as an alkaline aqueous solution, an aqueous developer, or an organic solvent. Among these, the development step using an alkaline aqueous solution is preferred. Furthermore, as the development method, known methods such as spraying, shaking immersion, brushing, and scraping can be appropriately employed.

[0163] Examples of alkaline aqueous solutions that can be used as developers include: aqueous solutions of alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, and potassium hydroxide; carbonates or bicarbonates such as sodium carbonate and sodium bicarbonate; alkali metal phosphates such as sodium phosphate and potassium phosphate; alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate; or aqueous solutions of organic bases that do not contain metal ions, such as tetraalkylammonium hydroxide. From the viewpoint that the absence of metal ions will not affect the semiconductor chip, an aqueous solution of tetramethylammonium hydroxide (TMAH) is preferred.

[0164] In order to improve the developing effect, surfactants, defoamers, etc., can be added to these alkaline aqueous solutions. The pH of the alkaline aqueous solution is preferably in the range of 8 to 12, and more preferably in the range of 9 to 11. Furthermore, the alkali concentration of the alkaline aqueous solution is preferably set to 0.1% to 10% by mass. The temperature of the alkaline aqueous solution can be appropriately selected according to the developability of the photosensitive resin composition layer, and is preferably set to 20°C to 50°C.

[0165] Organic solvents that can be used as developing solutions include, for example, acetone, ethyl acetate, alkoxyethanol having alkoxy groups with 1 to 4 carbon atoms, ethanol, isopropanol, butanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether.

[0166] The concentration of such organic solvent relative to the total amount of developer is preferably 2% to 90% by mass. Furthermore, the temperature of such organic solvent can be adjusted according to the developability. Moreover, such organic solvent can be used alone or in combination of two or more. Examples of organic solvent-based developers that can be used alone include, for example, 1,1,1-trichloroethane, N-methylpyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone.

[0167] In pattern formation, two or more of the above-mentioned developing methods can be used simultaneously as needed. Developing methods include immersion, spin-dip, spraying, high-pressure spraying, brushing, and scraping, with high-pressure spraying being preferred due to its improved resolution. When using the spraying method, the preferred spray pressure is 0.05 MPa to 0.3 MPa.

[0168] <Thermosetting (Post-baking) Process>

[0169] After the above developing process is completed, a heat curing (post-baking) process is performed to form the solder resist layer. Examples of post-baking processes include ultraviolet irradiation using a high-pressure mercury lamp and heating using a clean oven. When using ultraviolet irradiation, the irradiation dose can be adjusted as needed, for example, to 0.05 J / cm². 2 ~10J / cm 2Irradiation is performed at approximately [amount missing]. Furthermore, the heating conditions can be appropriately selected based on the type and content of the resin components in the photosensitive resin composition, preferably within the range of 150°C to 220°C for 20 to 180 minutes, and more preferably within the range of 160°C to 200°C for 30 to 120 minutes.

[0170] <Other Processes>

[0171] For printed circuit boards, after the solder mask layer is formed, the process may include opening vias and desmearing. These processes can be carried out according to various methods known to those skilled in the art in the manufacture of printed circuit boards.

[0172] After the solder mask layer is formed, a hole-opening process is performed on the solder mask layer formed on the circuit board to form through holes or vias, as needed. The hole-opening process can be carried out by known methods such as drilling, laser, and plasma, and these methods can be combined as needed. Preferably, the hole-opening process uses lasers such as carbon dioxide lasers or YAG lasers.

[0173] The resin residue removal process is a procedure to remove resin residue. The openings formed during the drilling process typically have resin residue (resin residue) adhering to them. This residue can cause poor electrical connections; therefore, this process involves removing the resin residue (resin residue removal treatment).

[0174] Degumming can be removed by dry degumming, wet degumming, or a combination thereof.

[0175] As a dry method for removing adhesive residue, plasma-based methods can be cited as examples. Plasma-based adhesive residue removal can be performed using commercially available plasma adhesive residue removal equipment. Examples of commercially available plasma adhesive residue removal equipment suitable for printed circuit board manufacturing include microwave plasma equipment manufactured by NISSIN Corporation and atmospheric pressure plasma etching equipment manufactured by Sekisui Chemicals Co., Ltd.

[0176] Examples of wet descaling treatments include descaling treatment using an oxidizing agent solution. When using an oxidizing agent solution for descaling, it is preferable to sequentially perform a swelling treatment using a swelling solution, an oxidation treatment using an oxidizing agent solution, and a neutralization treatment using a neutralizing solution. Examples of swelling solutions include "Swelling Dip Securiganth P" and "Swelling Dip Securiganth SBU" manufactured by ATOTECH JAPAN Co., Ltd. The swelling treatment is preferably performed by immersing the substrate with through-holes or the like in a swelling solution heated to 60°C to 80°C for 5 to 10 minutes. An alkaline permanganate aqueous solution is preferred as the oxidizing agent solution; examples include solutions obtained by dissolving potassium permanganate or sodium permanganate in an aqueous sodium hydroxide solution. The oxidation treatment using an oxidizing agent solution is preferably performed by immersing the swollen substrate in an oxidizing agent solution heated to 60°C to 80°C for 10 to 30 minutes. Commercially available alkaline permanganate solutions include, for example, "Concentrate Compact CP" and "Dosingsolution Securiganth P" manufactured by Ammet Japan Co., Ltd. Neutralization treatment using a neutralizing solution is preferably performed by immersing the oxidized substrate in a neutralizing solution at 30°C to 50°C for 3 to 10 minutes. An acidic aqueous solution is preferred as the neutralizing solution; commercially available examples include "Reduction solution Securiganth P" manufactured by Ammet Japan Co., Ltd.

[0177] When combining dry and wet degumming treatments, either the dry or wet degumming treatment can be performed first.

[0178] When the insulating layer is used as an interlayer insulating layer, it can be done in the same way as the solder resist layer. The opening process, the descaling process, and the plating process can be performed after the thermosetting process.

[0179] The plating process is the process of forming a conductor layer on an insulating layer. For the conductor layer, electroless plating and electrolytic plating can be combined to form it. Alternatively, a resist layer with a pattern opposite to the conductor layer can be formed, and the conductor layer can be formed using only electroless plating. As for the subsequent patterning method, subtractive or semi-additive methods known to those skilled in the art can be used, for example.

[0180] [Semiconductor Devices]

[0181] The semiconductor device of the present invention includes a printed wiring board. The semiconductor device of the present invention can be manufactured using the printed wiring board of the present invention.

[0182] As semiconductor devices, examples include various semiconductor devices used in electrical products (such as computers, mobile phones, digital cameras, and televisions) and vehicles (such as motorcycles, automobiles, trams, ships, and aircraft).

[0183] The semiconductor device of the present invention can be manufactured by mounting a component (semiconductor chip) on a conductive portion of a printed wiring board. A "conductive portion" refers to a portion of the printed wiring board that conducts electrical signals; its location can be on the surface or embedded. Furthermore, the semiconductor chip is not particularly limited to any electrical circuit element made of semiconductor material.

[0184] Regarding the mounting method of the semiconductor chip when manufacturing the semiconductor device of the present invention, there is no particular limitation as long as the semiconductor chip can function effectively. Specific examples include wire bonding mounting methods, flip chip mounting methods, mounting methods using a solderless built-in layer (BBUL), mounting methods using anisotropic conductive film (ACF), and mounting methods using non-conductive film (NCF). Here, "mounting method using a solderless built-in layer (BBUL)" refers to "a mounting method in which the semiconductor chip is directly embedded in a recess of a printed wiring board, thereby connecting the semiconductor chip to the wiring on the printed wiring board."

[0185] Example

[0186] The present invention will now be specifically described through embodiments, but the present invention is not limited to these embodiments. It should be noted that, unless otherwise expressly stated, in the following description, "parts" and "%" refer to "parts by mass" and "% by mass," respectively.

[0187] (Synthesis Example 1: Synthesis of Resin (A-1))

[0188] 162 parts of 1,1'-bis(2,7-diepoxypropoxynaphthyl)methane ("EXA-4700", manufactured by Dai Nippon Ink Chemical Industry Co., Ltd.) with an epoxy equivalent of 162 g / eq. were added to a flask equipped with a gas inlet tube, a stirrer, a condenser, and a thermometer. 340 parts of EDGAc (diethylene glycol monoethyl ether acetate, manufactured by Daicel Co., Ltd.) were added, and the mixture was heated to dissolve. 0.46 parts of hydroquinone and 1 part of triphenylphosphine were then added. The mixture was heated to 95–105°C, and 72 parts of acrylic acid were slowly added dropwise. The reaction was allowed to proceed for 16 hours. The reaction product was cooled to 80–90°C, and 80 parts of tetrahydrophthalic anhydride were added. The reaction was allowed to proceed for 8 hours, followed by cooling. This process yielded a resin solution with a solid acid value of 90 mg KOH / g (70% non-volatile components, hereinafter referred to as (A-1)).

[0189] <Manufacturing Examples 1 and 2>

[0190] Resin materials were mixed according to the following formula table, and resin varnishes 1 and 2 were obtained using a high-speed rotary mixer;

[0191] [Table 1]

[0192] (Table 1)

[0193]

[0194] The abbreviations in the table are as follows:

[0195] • (A-1) Composition: The resin (A-1) prepared in Synthesis Example 1, a solution of diethylene glycol monoethyl ether acetate with a solid content of 70%.

[0196] ZFR-1491H: An acid-modified epoxy acrylate containing a bisphenol F (bis-F) backbone, manufactured by Nippon Kayaku Co., Ltd., formulated with EDGAc, 70% solids.

[0197] Irgacure TPO: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, manufactured by BASF.

[0198] Irgacure OXE-02: 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-acetone 1-(O-acetyl oxime), manufactured by BASF

[0199] NC3000H: Biphenyl-type epoxy resin, manufactured by Nippon Kayaku Co., Ltd., with an epoxy equivalent of approximately 272 g / eq.

[0200] ZX1059: A mixed epoxy resin of bisphenol A and bisphenol F, manufactured by Nippon Steel & Sumitomo Metal Chemicals Co., Ltd., with an epoxy equivalent of approximately 165 g / eq.

[0201] ·1031S: Tetrahydroxyphenyl ethane type epoxy resin, manufactured by Mitsubishi Chemical Corporation, with an epoxy equivalent of approximately 200 g / eq.

[0202] • EDGAc: Diethylene glycol monoethyl ether acetate (carbidol acetate), manufactured by Daicel Corporation, boiling point 217.4℃

[0203] MEK: Methyl ethyl ketone, manufactured by Pure Chemical Co., Ltd., boiling point 79.6℃

[0204] ·DPHA: dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku Co., Ltd.

[0205] ·EBECRYL 3708: Modified epoxy acrylate, manufactured by Daicel-Zhenxin Co., Ltd.

[0206] SC2050: A material obtained by surface treatment of 100 parts by weight of molten silica (manufactured by Yaduma Co., Ltd., average particle size 0.5 μm) with 0.5 parts by weight of aminosilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM573).

[0207] •EP4-A: A material obtained by surface treatment of magnesium hydroxide with an average particle size of 0.8 μm with 1 part by mass of aminosilane (manufactured by Shin-Etsu Chemical Industry Co., Ltd., KBM573), manufactured by Kamishima Chemical Co., Ltd.

[0208] <Example 1>

[0209] As a support, a PET film ("LUMIRROR T6AM", Toray Industries, Ltd., 38 μm thick, softening point 130°C, "release PET") that has been released using an alkyd resin release agent ("AL-5", manufactured by Lintec Corporation) was prepared. Using a die-casting machine, a prepared resin varnish was uniformly applied to the release PET to achieve a dry photosensitive resin composition layer thickness of 25 μm, and dried at 80°C to 110°C (maximum 110°C) for 6 minutes. Next, a cover film (biaxially stretched polypropylene film, MA-411, manufactured by Oji F-Tex Corporation) was laminated onto the surface of the photosensitive resin composition layer at 80°C, thereby obtaining a three-layer structure photosensitive film with a support, consisting of the release PET, the photosensitive resin composition layer, and the cover film. Regarding lamination, a vacuum pressure laminator MVLP-500 manufactured by Nikko-Materials Co., Ltd. was used. After vacuuming for 30 seconds at 80°C, lamination was performed at a temperature of 80°C and a pressure of 7.0 kg / cm². 2 Under the specified conditions, the PET was laminated for 60 seconds through a heat-resistant rubber layer after demolding. Then, under atmospheric pressure, it was laminated using SUS end plates at a temperature of 80°C and a pressure of 5.5 kg / cm². 2 Conditional suppression for 90 seconds.

[0210] <Examples 2-5, Comparative Examples 1-3>

[0211] In Example 1, the drying time and the maximum drying temperature for obtaining the photosensitive film with the support were changed to the values ​​shown in the table below. Except for the above, the photosensitive film with the support was obtained by performing the same operation as in Example 1.

[0212] <Example 6, Comparative Example 4>

[0213] In Example 1, photosensitive resin composition 1 was changed to photosensitive resin composition 2, and the drying time and maximum drying temperature for obtaining the photosensitive film with the support were changed to the values ​​shown in the table below. Except for the above, the same procedure as in Example 1 was followed to obtain the photosensitive film with the support.

[0214] <Determination of weight loss rate>

[0215] The photosensitive films with supports obtained in the examples and comparative examples were cut into 10cm × 10cm pieces. These were placed in a desiccator with thoroughly dried silica gel and left for 30 minutes. Then, the mass of the photosensitive film with supports was measured with the cover film removed, and this value was designated as (a1) (in g). Next, the photosensitive film with supports was heated in an oven at 130°C for 15 minutes, and the mass of the photosensitive film with supports was measured again, and this value was designated as (a2) (in g). The value of a (weight loss rate when the photosensitive film with supports was dried at 130°C for 15 minutes) was calculated according to the above formula (A). Furthermore, for b (weight loss rate when the photosensitive film with supports was dried at 180°C for 15 minutes), the same procedure was performed as for the value of a, except that the oven temperature was set to 180°C, and the result was calculated according to the above formula (B). After calculating a and b, V and a / b were calculated.

[0216] <Determination of Melt Viscosity>

[0217] The photosensitive resin composition layer is peeled off only from the PET film with support and compressed through a mold to produce a small test piece (18 mm in diameter, 1.2–1.3 g). Using the test piece, a dynamic viscoelasticity measuring device (UBM Rheosol-G3000, UBM Corporation) is used. For a 1 g sample of the photosensitive resin composition layer, using a parallel plate with a diameter of 18 mm, the temperature is increased from an initial temperature of 60°C to 200°C at a heating rate of 5°C / min. The dynamic viscoelastic modulus is measured under the following conditions: a measurement temperature interval of 2.5°C, a vibration frequency of 1 Hz, and a deformation of 1 degree. The minimum melt viscosity (poise) is then calculated.

[0218] <Embedded Evaluation>

[0219] Prepare an inner layer circuit board (IPC Multi-Purpose Test Board No. IPC-B-25, conductor thickness 18μm, thickness 0.8mm). After peeling off the cover film of the photosensitive film with support, laminate the photosensitive film with support on both sides of the inner layer circuit board using a batch vacuum pressure laminator (Nikko-Materials Co., Ltd., VP160) to bond the photosensitive resin composition layer to the inner layer circuit board. The lamination process is as follows: after depressurization for 30 seconds to bring the pressure down to below 13hPa, press for 30 seconds at 90°C and 0.7MPa. Then, perform hot pressing for 60 seconds at 90°C and 0.5MPa.

[0220] The appearance of the laminated inner layer circuit board was visually inspected and evaluated according to the following criteria:

[0221] ○: There are no gaps between the copper wires, and the resin seepage from the outer edge of the support is less than 1cm.

[0222] △: Only a small number of pores are visible;

[0223] ×: The resin seepage is more than 1 cm.

[0224] <Evaluation of residue at the bottom of the through hole and resistance to undercut>

[0225] (Preparation of the evaluation laminate)

[0226] The copper layer of a glass epoxy board (copper-clad laminate) with a circuit formed by patterning a copper layer with a thickness of 18 μm was roughened by treatment with a surface treatment agent containing organic acid (CZ8100, manufactured by MEC Corporation). Next, a photosensitive resin composition layer with a support, obtained through the examples and comparative examples, was deposited on the surface of the copper circuit using a vacuum laminator (manufactured by Nikko-Materials Corporation, VP160) to form a laminate in which the copper-clad laminate, the photosensitive resin composition layer, and the support are sequentially stacked. The bonding conditions were set as follows: vacuum time 30 seconds, bonding temperature 90°C, bonding pressure 0.7 MPa, and bonding time 30 seconds. The laminate was left to stand at room temperature for at least 30 minutes, and a circular hole pattern was formed on the support of the laminate, which was then exposed to ultraviolet light using a patterning apparatus. The exposure pattern was created using a quartz glass mask with a 100 μm circular aperture (through-hole). After standing at room temperature for 30 minutes, the support was peeled off from the laminate. The entire surface of the photosensitive resin composition layer on the laminate was spray-developed for 2 minutes using a 1% by mass sodium carbonate aqueous solution at 30°C as the developer at a spray pressure of 0.2 MPa. After spray development, a 1 J / cm² exposure was performed.2 The laminate is subjected to ultraviolet irradiation and then heat treatment at 180°C for 30 minutes to form an insulating layer with openings. This laminate is used for evaluation.

[0227] (Evaluation of residue at the bottom of the through hole)

[0228] The evaluation of 100 μm circular holes formed in the evaluation laminate was conducted according to the following criteria.

[0229] ○: No residue;

[0230] ×: Residue was observed.

[0231] (Evaluation of undercut resistance)

[0232] For the 100 μm circular hole formed in the evaluation laminate, a cross-sectional observation was performed using SEM. The radius (μm) of the uppermost part of the cross-section and the radius (μm) of the bottom part were measured, and their difference (radius of the uppermost part - radius of the bottom part) was calculated.

[0233] [Table 2]

[0234] (Table 2)

[0235]

[0236] It was confirmed that in each embodiment, even without components (E) and (F), although the degree of difference was different, the result was the same as that in the embodiments described above.

Claims

1. A photosensitive resin composition, which is a photosensitive resin composition containing the following (A) to (D) components, (A) a resin containing an ethylenically unsaturated group and a carboxyl group, (B) a photopolymerization initiator, (C) an epoxy resin, and (D) a volatile component, wherein the (A) component contains a structure from an epoxy resin containing a naphthalene skeleton, when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (A) component is 10% by mass or greater, when the weight reduction rate (%) of the photosensitive resin composition when dried at 130°C for 15 minutes is taken as a, and when the weight reduction rate (%) of the photosensitive resin composition when dried at 180°C for 15 minutes is taken as b, the following relationships of formula (1) and formula (2) are satisfied: V = a 2 + b 2 where V < 30 (1) a / b < 0.6 (2).

2. The photosensitive resin composition according to claim 1, wherein V is 28 or less.

3. The photosensitive resin composition according to claim 1, wherein V is 26 or less.

4. The photosensitive resin composition according to claim 1, wherein V is 1 or greater.

5. The photosensitive resin composition according to claim 1, wherein V is 5 or greater.

6. The photosensitive resin composition according to claim 1, wherein a / b is 0.55 or less.

7. The photosensitive resin composition according to claim 1, wherein a / b is 0.48 or less.

8. The photosensitive resin composition according to claim 1, wherein a / b is 0.01 or greater.

9. The photosensitive resin composition according to claim 1, wherein a / b is 0.1 or greater.

10. The photosensitive resin composition according to claim 1, further comprising (E) a reactive diluent.

11. The photosensitive resin composition according to claim 10, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (E) component is 1% by mass or greater.

12. The photosensitive resin composition according to claim 10, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (E) component is 3% by mass or greater.

13. The photosensitive resin composition according to claim 10, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (E) component is 25% by mass or less.

14. The photosensitive resin composition according to claim 10, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (E) component is 15% by mass or less.

15. The photosensitive resin composition according to claim 1, further comprising (F) an inorganic filler material.

16. The photosensitive resin composition according to claim 15, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (F) component is 10% by mass or greater.

17. The photosensitive resin composition according to claim 15, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (F) component is 25% by mass or greater.

18. The photosensitive resin composition according to claim 15, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (F) component is 90% by mass or less.

19. The photosensitive resin composition according to claim 15, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (F) component is 70% by mass or less.

20. The photosensitive resin composition according to claim 1, wherein the (A) component includes an acid-modified unsaturated epoxy ester resin.

21. The photosensitive resin composition according to claim 1, wherein the (A) component includes an acid-modified epoxy (meth)acrylate.

22. The photosensitive resin composition according to claim 1, wherein the (A) component includes an acid-modified epoxy (meth)acrylate containing a naphthalene skeleton.

23. The photosensitive resin composition according to claim 1, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (A) component is 15% by mass or greater.

24. The photosensitive resin composition according to claim 1, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (A) component is 40% by mass or less.

25. The photosensitive resin composition according to claim 1, wherein when the nonvolatile component in the photosensitive resin composition is taken as 100% by mass, the content of the (A) component is 25% by mass or less.

26. The photosensitive resin composition according to claim 1, wherein the (B) component includes either an acylphosphine oxide-based photopolymerization initiator or an oxime ester-based photopolymerization initiator.

27. The photosensitive resin composition according to claim 1, wherein The content of the (B) component is 0.001 mass% or more, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

28. The photosensitive resin composition according to claim 1, wherein The content of the (B) component is 0.01 mass% or more, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

29. The photosensitive resin composition according to claim 1, wherein The content of the (B) component is 3 mass% or less, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

30. The photosensitive resin composition according to claim 1, wherein The content of the (B) component is 0.5 mass% or less, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

31. The photosensitive resin composition according to claim 1, wherein The content of the (C) component is 1 mass% or more, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

32. The photosensitive resin composition according to claim 1, wherein The content of the (C) component is 3 mass% or more, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

33. The photosensitive resin composition according to claim 1, wherein The content of the (C) component is 20 mass% or less, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

34. The photosensitive resin composition according to claim 1, wherein The content of the (C) component is 12 mass% or less, based on 100 mass% of nonvolatile components in the photosensitive resin composition.

35. The photosensitive resin composition according to claim 1, wherein The (D) component has any one of a ketone and a glycol ether.

36. A photosensitive film comprising the photosensitive resin composition according to any one of claims 1 to 35.

37. A photosensitive film with a support, comprising: a support, and a photosensitive resin composition layer comprising the photosensitive resin composition according to any one of claims 1 to 35 disposed on the support.

38. A printed wiring board comprising an insulating layer formed using a cured product of the photosensitive resin composition according to any one of claims 1 to 35.

39. The printed wiring board of claim 38 wherein, The insulating layer is a solder resist layer.

40. A semiconductor device comprising the printed wiring board according to claim 38.

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