JP6720910B2 - Photosensitive resin composition - Google Patents

Description

The present invention relates to a photosensitive resin composition. Further, the present invention relates to a photosensitive film, a photosensitive film with a support, a printed wiring board, and a semiconductor device obtained by using the photosensitive resin composition.

In a printed wiring board, a solder resist may be provided as a permanent protective film for preventing the solder from adhering to a portion where the solder is unnecessary and for preventing the circuit board from corroding. As the solder resist, it is common to use a photosensitive resin composition as described in Patent Document 1, for example.

JP, 2014-115672, A

Photosensitive resin compositions for solder resist generally have resolution, insulation, solder heat resistance, gold plating resistance, moist heat resistance, crack resistance (TCT resistance), and super-acceleration high-temperature high temperature between fine wiring lines. HAST resistance to the wet life test (HAST) is required. In recent years, workability and higher performance have been demanded of solder resists in response to higher density of printed wiring boards. In particular, the demand for crack resistance is increasing year by year, and it is important to have further durability.

In addition, the solder resist is required to have a fine opening pattern such that a part of the conductor layer having a wiring pattern is exposed in order to connect the substrates by soldering. Therefore, it is required that the opening shape of this opening portion does not have an inverse tapered shape. Here, the inverse tapered opening shape means a shape that is wider toward the inner side of the opening. In the present application, the property that the opening shape is unlikely to be the inverse taper shape may be excellent in “undercut resistance”.

The object of the present invention is to provide a photosensitive resin composition having a low average linear thermal expansion coefficient, a high glass transition temperature, an undercut resistance, and a cured product having excellent crack resistance, and having excellent resolution; To provide a photosensitive film, a photosensitive film with a support, a printed wiring board, and a semiconductor device, which are obtained by using a photosensitive resin composition.

Generally, when a large amount of an inorganic filler having a large average particle size is contained, light reflection occurs, resulting in poor resolution. For this reason, conventionally, a large amount of an inorganic filler having an average particle size of less than 0.5 μm is contained in the photosensitive resin composition. However, the present inventors have made it possible for the average particle diameter to be 0.5 μm or more and 2.5 μm or less by incorporating both the specific component (A) and the specific photopolymerization initiator component into the photosensitive resin composition. The inventors have found that even when a large amount of an inorganic filler larger than the average particle size of the inorganic filler used has been contained, light reflection is suppressed and the resolution and the like are improved, and the present invention has been completed.

That is, the present invention includes the following contents.
[1] (A) A resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group,
(B) an inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less,
A photosensitive resin composition containing (C) an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator, and (D) an epoxy resin,
The content of the component (B) is 60% by mass or more and 85% by mass or less, based on the total solid content of the photosensitive resin composition as 100% by mass.
[2] Component (C) is bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), and 1,2- The photosensitive resin composition according to [1], which is any one of octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)].
[3] The photosensitive resin composition according to [1] or [2], in which the component (A) contains an acid-modified naphthalene skeleton-containing epoxy (meth)acrylate.
[4] The photosensitive resin composition according to any one of [1] to [3], wherein the component (D) contains at least one of a biphenyl type epoxy resin and a tetraphenylethane type epoxy resin.
[5] The photosensitive resin composition according to any one of [1] to [4], wherein the component (B) contains silica.
[6] A photosensitive film containing the photosensitive resin composition according to any one of [1] to [5].
[7] A photosensitive material with a support, which has a support and a photosensitive resin composition layer containing the photosensitive resin composition according to any one of [1] to [5], which is provided on the support. Film.
[8] A printed wiring board including an insulating layer formed from the cured product of the photosensitive resin composition according to any one of [1] to [5].
[9] The printed wiring board according to [8], wherein the insulating layer is a solder resist.
[10] A semiconductor device including the printed wiring board according to [8] or [9].

According to the present invention, it is possible to obtain a cured product having a high glass transition temperature, excellent undercut resistance, and crack resistance, and a photosensitive resin composition having excellent resolution; obtained using the photosensitive resin composition. It is possible to provide a photosensitive film, a photosensitive film with a support, a printed wiring board, and a semiconductor device.

Hereinafter, the photosensitive resin composition, the photosensitive film, the photosensitive film with a support, the printed wiring board, and the semiconductor device of the present invention will be described in detail.

[Photosensitive resin composition]
The photosensitive resin composition of the present invention comprises (A) a resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group, and (B) an inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less. And (C) an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator, and (D) an epoxy resin, wherein the content of the component (B) is When the total solid content of the photosensitive resin composition is 100% by mass, the content is 60% by mass or more and 85% by mass or less.

As described above, conventionally, a large amount of inorganic filler having an average particle size of less than 0.5 μm has been contained in the photosensitive resin composition. However, in the present invention, by including both the component (A) and the component (C) in the photosensitive resin composition, a large amount of inorganic filler having an average particle diameter larger than that of the conventionally used inorganic filler is used. Also, the light reflection is suppressed, the resolution is improved, as a result, it is possible to obtain a cured product having a high glass transition temperature, undercut resistance, and crack resistance, and a photosensitive resin composition having excellent resolution. You will be able to provide things.

The resin composition may further contain (E) a reactive diluent and (F) an organic solvent, if necessary. Hereinafter, each component contained in the photosensitive resin composition will be described in detail.

<(A) Resin Containing Naphthalene Skeleton, Ethylenically Unsaturated Group, and Carboxyl Group>
The photosensitive resin composition contains (A) a resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group. By incorporating the component (A) in the photosensitive resin composition together with the component (C) described below, light reflection is suppressed and the resolution is improved even when the component (B) described below is used. In addition, a cured product having a high glass transition temperature and excellent undercut resistance and crack resistance can be obtained, and a photosensitive resin composition having excellent resolution can be provided.

Examples of the ethylenically unsaturated group include a vinyl group, an allyl group, a propargyl group, a butenyl group, an ethynyl group, a phenylethynyl group, a maleimide group, a nadiimide group, and a (meth)acrylic group, which are reactive to photoradical polymerization. From the viewpoint of, a (meth)acrylic group is preferable. The “(meth)acrylic group” refers to a methacrylic group and an acrylic group.

The component (A) has a resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group, and is not particularly limited as long as it is a compound capable of radical photopolymerization and alkali development. A resin having a naphthalene skeleton, a carboxyl group, and two or more ethylenically unsaturated groups in one molecule is preferable. When the naphthalene skeleton is contained, the rigidity of the molecule becomes high, so that the movement of the molecule is suppressed, and as a result, the glass transition temperature of the cured product becomes higher and the average linear thermal expansion coefficient of the cured product becomes lower.

As one mode of the component (A), a naphthalene-type epoxy compound having a naphthalene skeleton (epoxy compound containing a naphthalene skeleton) is reacted with an unsaturated carboxylic acid, and an acid anhydride is further reacted to contain an acid-modified unsaturated naphthalene skeleton. Examples thereof include epoxy ester resin. Specifically, an unsaturated carboxylic acid is reacted with a naphthalene skeleton-containing epoxy compound to obtain an unsaturated naphthalene skeleton-containing epoxy ester resin, and the unsaturated naphthalene skeleton-containing epoxy ester resin is reacted with an acid anhydride to form an acid-modified unsaturated naphthalene. A skeleton-containing epoxy ester resin can be obtained.

As the naphthalene skeleton-containing epoxy compound, any compound having two or more epoxy groups in the molecule can be used, and specifically, dihydroxynaphthalene-type epoxy resin, polyhydroxybinaphthalene-type epoxy resin, polyhydroxynaphthalene, and the like. Examples thereof include naphthalene-type epoxy resins having a naphthalene skeleton in the molecule, such as naphthalene-type epoxy resins and binaphthol-type epoxy resins obtained by condensation reaction with aldehydes. Any of these may be used alone or in combination of two or more.

Examples of the dihydroxynaphthalene type epoxy resin include 1,3-diglycidyloxynaphthalene, 1,4-diglycidyloxynaphthalene, 1,5-diglycidyloxynaphthalene, 1,6-diglycidyloxynaphthalene, and 2,3-diglycidyloxynaphthalene. Examples thereof include glycidyloxynaphthalene, 2,6-diglycidyloxynaphthalene, and 2,7-diglycidyloxynaphthalene.

Examples of the polyhydroxy binaphthalene type epoxy resin include 1,1′-bi-(2-glycidyloxy)naphthyl, 1-(2,7-diglycidyloxy)-1′-(2′-glycidyloxy)binaphthyl, 1,1'-bi-(2,7-diglycidyloxy)naphthyl and the like can be mentioned.

Examples of the naphthalene-type epoxy resin obtained by the condensation reaction of polyhydroxynaphthalene and aldehydes include 1,1'-bis(2,7-diglycidyloxynaphthyl)methane and 1-(2,7-diglycidyloxynaphthyl). )-1'-(2'-glycidyloxynaphthyl)methane and 1,1'-bis(2-glycidyloxynaphthyl)methane.

Among these, a polyhydroxybinaphthalene type epoxy resin having two or more naphthalene skeletons in one molecule, and a naphthalene type epoxy resin obtained by a condensation reaction of polyhydroxynaphthalene and aldehydes are preferable, and particularly epoxy in one molecule. 1,1′-bis(2,7-diglycidyloxynaphthyl)methane having 3 or more groups, 1-(2,7-diglycidyloxynaphthyl)-1′-(2′-glycidyloxynaphthyl)methane, 1-(2,7-diglycidyloxy)-1'-(2'-glycidyloxy)binaphthyl and 1,1'-bi-(2,7-diglycidyloxy)naphthyl are added to the average linear thermal expansion coefficient. It is preferable in terms of excellent heat resistance.

Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, cinnamic acid, crotonic acid, etc. These may be used alone or in combination of two or more. Among them, acrylic acid and methacrylic acid are preferable from the viewpoint of improving the photocurability of the photosensitive resin composition. In this specification, the naphthalene-type epoxy compound ester resin, which is a reaction product of the above-mentioned naphthalene-type epoxy compound and (meth)acrylic acid, may be referred to as “naphthalene-type epoxy compound (meth)acrylate”, Here, the epoxy group of the naphthalene type epoxy compound is substantially eliminated by the reaction with (meth)acrylic acid. “(Meth)acrylate” refers to methacrylate and acrylate. Acrylic acid and methacrylic acid may be collectively referred to as “(meth)acrylic acid”.

As the acid anhydride, for example, maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic acid dicarboxylic acid. Examples thereof include anhydrides, and any of these may be used alone or in combination of two or more. Among them, succinic anhydride and tetrahydrophthalic anhydride are preferable from the viewpoint of improving the resolution and insulation reliability of the cured product.

In obtaining an acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin, an unsaturated carboxylic acid and a naphthalene skeleton-containing epoxy compound are reacted in the presence of a catalyst to obtain an unsaturated naphthalene skeleton-containing epoxy ester resin, and then an unsaturated naphthalene skeleton-containing You may make an epoxy ester resin and an acid anhydride react.

The amount of the catalyst used in this case is preferably 2% by mass or less, more preferably 0.0005% by mass to 1 with respect to the total mass of the unsaturated carboxylic acid, the naphthalene skeleton-containing epoxy compound and the acid anhydride. It is in the range of mass%, and more preferably in the range of 0.001 mass% to 0.5 mass%. Examples of the catalyst include N-methylmorpholine, pyridine, 1,8-diazabicyclo[5.4.0]undecene-7(DBU), 1,5-diazabicyclo[4.3.0]nonene-5(DBN). ), 1,4-diazabicyclo[2.2.2]octane (DABCO), tri-n-butylamine or dimethylbenzylamine, butylamine, octylamine, monoethanolamine, diethanolamine, triethanolamine, imidazole, 1-methylimidazole. , 2,4-dimethylimidazole, 1,4-diethylimidazole, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(N-phenyl)aminopropyltrimethoxysilane, 3-(2-amino Various amine compounds such as ethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropylmethyldimethoxysilane and tetramethylammonium hydroxide; phosphines such as trimethylphosphine, tributylphosphine and triphenylphosphine; tetramethyl A phosphonium salt such as phosphonium salt, tetraethylphosphonium salt, tetrapropylphosphonium salt, tetrabutylphosphonium salt, trimethyl(2-hydroxypropyl)phosphonium salt, triphenylphosphonium salt, and benzylphosphonium salt, and as a typical counter anion, Chlorides, bromides, carboxylates, phosphonium salts having a hydroxide, etc.; sulfonium salts such as trimethylsulfonium salt, benzyltetramethylenesulfonium salt, phenylbenzylmethylsulfonium salt or phenyldimethylsulfonium salt, and as typical counter anions, Sulfonium salts having carboxylate, hydroxide and the like; acidic compounds such as phosphoric acid, p-toluenesulfonic acid, sulfuric acid and the like can be mentioned. The reaction can be carried out in the range of 50°C to 150°C, preferably 80°C to 120°C.

In obtaining the acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin, an organic solvent may be used, and as the organic solvent, the same organic solvent as (F) organic solvent described later can be used.

In obtaining the acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin, a polymerization inhibitor such as hydroquinone may be used. The amount of the polymerization inhibitor used at this time is preferably 2% by mass or less, and more preferably 0.0005% by mass, based on the total mass of the unsaturated carboxylic acid, the naphthalene skeleton-containing epoxy compound and the acid anhydride. To 1% by mass, more preferably 0.001% to 0.5% by mass.

The acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin is preferably an acid-modified naphthalene skeleton-containing epoxy (meth)acrylate. The acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin refers to an acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin obtained by using a naphthalene skeleton-containing epoxy compound and (meth)acrylic acid as the unsaturated carboxylic acid. ..

In another embodiment of the component (A), a (meth)acrylic resin having a structural unit obtained by polymerizing (meth)acrylic acid is reacted with an ethylenically unsaturated group- and naphthalene skeleton-containing epoxy compound to form an ethylenic compound. Examples thereof include unsaturated modified naphthalene skeleton-containing (meth)acrylic resins having an unsaturated group introduced therein. Furthermore, it is also possible to react an acid anhydride with the hydroxyl group generated when the unsaturated group is introduced. As the acid anhydride, those similar to the above-mentioned acid anhydride can be used, and the preferable range is also the same.

The weight average molecular weight of the component (A) is preferably 1000 or more, more preferably 1500 or more, and further preferably 2000 or more, from the viewpoint of film-forming property. From the viewpoint of developability, the upper limit is preferably 10,000 or less, more preferably 8,000 or less, and further preferably 7500 or less. The weight average molecular weight is a polystyrene equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

The acid value of the component (A) is preferably 0.1 mgKOH/g or more, more preferably 0.5 mgKOH/g or more, from the viewpoint of improving the alkali developability of the photosensitive resin composition. Is more preferable, and 1 mgKOH/g or more is further preferable. On the other hand, the acid value is preferably 150 mgKOH/g or less, more preferably 120 mgKOH/g or less, from the viewpoint of suppressing dissolution of the fine pattern of the cured product by development and improving insulation reliability. It is more preferably 100 mgKOH/g or less. Here, the acid value is the residual acid value of the carboxyl group present in the component (A), and the acid value can be measured by the following method. First, about 1 g of the measured resin solution is precisely weighed, and then 30 g of acetone is added to the resin solution to uniformly dissolve the resin solution. Next, an appropriate amount of phenolphthalein, which is an indicator, is added to the solution, and titration is performed using a 0.1N KOH aqueous solution. Then, the acid value is calculated by the following formula.
Formula: A=10×Vf×56.1/(Wp×I)

In the above formula, A represents an acid value (mgKOH/g), Vf represents a titration amount (mL) of KOH, Wp represents a measured resin solution mass (g), and I represents a nonvolatile content of the measured resin solution. Represents the ratio (mass %).

In the production of the component (A), from the viewpoint of improving storage stability, the ratio of the number of moles of epoxy groups of the naphthalene type epoxy resin to the number of moles of total carboxyl groups of unsaturated carboxylic acid and acid anhydride is , 1:0.8 to 1.3 is preferable, and 1:0.9 to 1.2 is more preferable.

From the viewpoint of improving alkali developability, the component (A) preferably has a content of 5% by mass or more, and 8% by mass or more, when the total solid content of the photosensitive resin composition is 100% by mass. And more preferably 10% by mass or more. From the viewpoint of improving heat resistance, the upper limit is preferably 35% by mass or less, more preferably 30% by mass or less, and further preferably 25% by mass or less.

<(B) Inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less>
The photosensitive resin composition contains (B) an inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less. By containing the component (B), it is possible to provide a photosensitive resin composition that can obtain a cured product having a low average coefficient of linear thermal expansion.

The material of the inorganic filler is not particularly limited, for example, silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, water. Aluminum oxide, 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 titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium phosphate tungstate. Among these, silica is particularly suitable. Spherical silica is preferable as the silica. The inorganic fillers may be used alone or in combination of two or more.

The average particle size of the inorganic filler needs to contain a large amount of the inorganic filler in order to obtain a cured product having a low average linear thermal expansion coefficient, and from the viewpoint of the filling property, it is 0.5 μm or more, preferably 0. It is 8 μm or more, more preferably 1 μm or more. From the viewpoint of obtaining excellent resolution, the upper limit of the average particle size is 2.5 μm or less, preferably 2 μm or less, more preferably 1.5 μm or less, and further preferably 1.3 μm or less. Examples of commercially available inorganic fillers having such an average particle diameter include "SC4050" and "Admafine" manufactured by Admatechs, "SFP series" manufactured by Denki Kagaku Kogyo, and "SP" manufactured by Nippon Steel & Sumikin Materials Co., Ltd. (H) Series", Sakai Chemical Industry's "Siqas Series", Nippon Shokubai's "Sea Star Series", Nippon Steel & Sumikin Materials' "AZ Series", "AX Series", Sakai Chemical Industry's "Series" "B series", "BF series" and the like.

The average particle size of the inorganic filler can be measured by a laser diffraction/scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler can be created on a volume basis using a laser diffraction/scattering particle size distribution measuring device, and the median size can be used as the average particle size for measurement. As the measurement sample, an inorganic filler dispersed in water by ultrasonic waves can be preferably used. As the laser diffraction/scattering type particle size distribution measuring device, "LA-500" manufactured by Horiba, Ltd., "SALD-2200" manufactured by Shimadzu, etc. can be used.

The inorganic filler is an aminosilane coupling agent, an epoxysilane coupling agent, a mercaptosilane coupling agent, a silane coupling agent, an alkoxysilane compound, an organosilazane compound, or a titanate, from the viewpoint of improving moisture resistance and dispersibility. It is preferably treated with at least one surface treatment agent such as a system coupling agent. Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., Shin-Etsu Chemical industry "KBE903" (3-aminopropyltriethoxysilane), Shin-Etsu Chemical industry "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane), Shin-Etsu Chemical industry "SZ-31" ( Hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd. "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "KBM-4803" (long-chain epoxy type silane coupling agent), and the like.

The content of the inorganic filler is 60% by mass or more, preferably 60% by mass, when the nonvolatile component in the photosensitive resin composition is 100% by mass, from the viewpoint of obtaining a cured product having a low average linear thermal expansion coefficient. It is 5% by mass or more, and more preferably 61% by mass or more. From the viewpoint of suppressing light reflection, the upper limit is 85% by mass or less, preferably 82% by mass or less, and more preferably 80% by mass or less.

<(C) Acylphosphine oxide-based photopolymerization initiator or oxime ester-based photopolymerization initiator>
The photosensitive resin composition contains (C) an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator. By including the component (C) in the photosensitive resin composition together with the component (A), light reflection is suppressed even when the component (B) having a large average particle diameter is used. As a result, a cured product having a high glass transition temperature and excellent undercut resistance and crack resistance can be obtained, and a photosensitive resin composition having excellent resolution can be provided.

The acylphosphine oxide photopolymerization initiator is not particularly limited as long as it is a photopolymerization initiator having an acylphosphine oxide group. Specific examples of the acylphosphine oxide photopolymerization initiator include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide) and 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide. .. Examples of commercially available acylphosphine oxide photopolymerization initiators include "IRGACURE TPO" and "IRGACURE 819" manufactured by BASF.

The oxime ester photopolymerization initiator is not particularly limited as long as it is a photopolymerization initiator having an oxime ester group. Specific examples of the oxime ester photopolymerization initiator include 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6- (2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime) and the like. Examples of commercially available oxime ester photopolymerization initiators include "IRGACURE OXE01" and "IRGACURE OXE02" manufactured by BASF.

Among these, the component (C) is bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide) or bis(2,4,6-trimethylbenzoyl)-phenyl from the viewpoint of improving resolution. Phosphine oxide) and 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)] are preferred. As the component (C), one type may be used alone, or two or more types may be used in combination.

Further, the photosensitive resin composition is used in combination with the component (C) as a photopolymerization initiation aid, N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, pentyl-4- It may contain tertiary amines such as dimethylaminobenzoate, triethylamine and triethanolamine, and may also contain photosensitizers such as pyrarizones, anthracenes, coumarins, xanthones and thioxanthones. Good. These may be used alone or in combination of two or more.

The content of the component (C) is preferably 100% by mass of the total solid content of the photosensitive resin composition, from the viewpoint of sufficiently photocuring the photosensitive resin composition and improving the insulation reliability. It is 0.01 mass% or more, more preferably 0.03 mass% or more, and further preferably 0.05 mass% or more. On the other hand, the upper limit is preferably 2% by mass or less, more preferably 1.5% by mass or less, and further preferably 1% by mass or less, from the viewpoint of suppressing a decrease in resolution due to excessive sensitivity.

<(D) Epoxy resin>
The photosensitive resin composition contains (D) an epoxy resin. By including the component (D), insulation reliability can be improved. However, the component (D) mentioned here does not include an epoxy resin containing a naphthalene skeleton, an ethylenically unsaturated group and a carboxyl group.

Examples of the component (D) include fluorine-containing epoxy resins such as bisphenol AF type epoxy resin and perfluoroalkyl type epoxy resin; bisphenol A type epoxy resin; bisphenol F type epoxy resin; bisphenol S type epoxy resin; bixylenol type Epoxy resin; dicyclopentadiene type epoxy resin; trisphenol type epoxy resin; naphthol novolac type epoxy resin; phenol novolac type epoxy resin; tert-butyl-catechol type epoxy resin; naphthalene type epoxy resin; naphthol type epoxy resin; anthracene type epoxy resin Resin; Glycidylamine type epoxy resin; Glycidyl ester type epoxy resin; Cresol novolac type epoxy resin; Biphenyl type epoxy resin; Linear aliphatic epoxy resin; Epoxy resin having butadiene structure; Alicyclic epoxy resin, Fat having ester skeleton Cyclic epoxy resin; Heterocyclic epoxy resin; Spiro ring-containing epoxy resin; Cyclohexanedimethanol type epoxy resin; Naphthylene ether type epoxy resin; Trimethylol type epoxy resin; Tetraphenylethane type epoxy resin, halogenated epoxy resin, etc. From the viewpoint of improving adhesion, a bisphenol F type epoxy resin and a biphenyl type epoxy resin are preferable, and a biphenyl type epoxy resin is more preferable. Further, from the viewpoint of improving heat resistance, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, naphthylene ether type epoxy resin, tetraphenylethane type epoxy resin are preferable, and tetraphenylethane type epoxy resin is more preferable. .. The epoxy resins may be used alone or in combination of two or more. From the viewpoint of improving adhesion and heat resistance, the component (D) preferably contains at least one of a biphenyl type epoxy resin and a tetraphenylethane type epoxy resin.

The epoxy resin preferably contains an epoxy resin having two or more epoxy groups in one molecule. When the nonvolatile component of the epoxy resin is 100% by mass, at least 50% by mass or more is preferably an epoxy resin having two or more epoxy groups in one molecule. As the component (E), two or more epoxy resins may be used in combination.

Specific examples of the epoxy resin include "HP4032", "HP4032D", "HP4032SS", "HP4032H" (naphthalene type epoxy resin) manufactured by DIC, "828US" and "jER828EL" (bisphenol A type) manufactured by Mitsubishi Chemical Corporation. Epoxy resin), "jER807" (bisphenol F type epoxy resin), "jER152" (phenol novolac type epoxy resin), "630", "630LSD" (glycidylamine type epoxy resin), "ZX1059" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. (Mixed product of bisphenol A type epoxy resin and bisphenol F type epoxy resin), Nippon Steel & Sumitomo Metal Corporation "YD-8125G" (bisphenol A type epoxy resin), Nagase Chemtex's "EX-721" (glycidyl ester type) Epoxy resin), "Celoxide 2021P" (alicyclic epoxy resin having an ester skeleton) manufactured by Daicel, "PB-3600" (epoxy resin having a butadiene structure), "ZX1658" manufactured by Nippon Steel Chemical Co., Ltd. ZX1658GS" (liquid 1,4-glycidyl cyclohexane), "630LSD" (glycidyl amine type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd., "E-7432", "E-7632" (perfluoroalkyl type epoxy) manufactured by Daikin Industries, Ltd. Resin), "HP-4700", "HP-4710" (naphthalene type tetrafunctional epoxy resin), "N-690" (cresol novolac type epoxy resin), "N-695" (cresol novolac type epoxy) manufactured by DIC. Resin), "HP-7200", "HP-7200HH", "HP-7200H" (dicyclopentadiene type epoxy resin), "EXA-7311", "EXA-7311-G3", "EXA-7311-G4". , "EXA-7311-G4S", "HP6000" (naphthylene ether type epoxy resin), "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. , "NC3000H", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin), "ESN475V" (naphthalene type epoxy resin) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., "ESN485" (naphthol novolac type epoxy resin), "YSLV-80XY" (tetramethylbisphenol F type epoxy resin), "YX4000H", "YL61" manufactured by Mitsubishi Chemical Corporation. 21" (biphenyl type epoxy resin), "YX4000HK" (bixylenol type epoxy resin), "YX8800" (anthracene type epoxy resin), "PG-100", "CG-500" manufactured by Osaka Gas Chemicals, Mitsubishi Chemical "YL7800" (fluorene type epoxy resin), Mitsubishi Chemical "1010" (solid bisphenol A type epoxy resin), "1031S" (tetraphenylethane type epoxy resin), "YL7760" (bisphenol AF type) Epoxy resin) and the like.

The content of the component (D) is preferably 1% by mass or more when the total solid content of the photosensitive resin composition is 100% by mass from the viewpoint of obtaining an insulating layer exhibiting good tensile breaking strength and insulation reliability. , More preferably 5% by mass or more, further preferably 8% by mass or more. The upper limit of the content of the epoxy resin is not particularly limited as long as the effects of the present invention are exhibited, but is preferably 25% by mass or less, more preferably 20% by mass or less, and further preferably 15% by mass or less.

The epoxy equivalent of the epoxy resin is preferably 50 to 5000, more preferably 50 to 3000, even more preferably 80 to 2000, and even more preferably 110 to 1000. Within this range, the cross-linking density of the cured product of the photosensitive resin composition will be sufficient, and an insulating layer having a small surface roughness can be provided. The epoxy equivalent can be measured according to JIS K7236, and is the mass of the resin containing one equivalent of epoxy group.

The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and further preferably 400 to 1500. Here, the weight average molecular weight of the epoxy resin is a polystyrene equivalent weight average molecular weight measured by a gel permeation chromatography (GPC) method.

<(E) Reactive diluent>
The photosensitive resin composition may further contain (E) a reactive diluent. By incorporating the component (E), photoreactivity can be improved. As the component (E), for example, a photosensitive (meth)acrylate compound which has one or more (meth)acryloyl groups in one molecule and is liquid, solid or semi-solid at room temperature can be used. Room temperature refers to about 25°C. The “(meth)acryloyl group” refers to an acryloyl group and a methacryloyl group.

Typical photosensitive (meth)acrylate compounds include, for example, hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate and 2-hydroxybutyl acrylate, and glycols such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol and propylene glycol. Mono- or diacrylates, acrylamides such as N,N-dimethylacrylamide and N-methylolacrylamide, aminoalkyl acrylates such as N,N-dimethylaminoethyl acrylate, and polyacetals such as trimethylolpropane, pentaerythritol, and dipentaerythritol. Polyhydric acrylates of polyhydric alcohols or adducts of ethylene oxide, propylene oxide or ε-caprolactone, phenols such as phenoxy acrylate and phenoxyethyl acrylate, or acrylates such as ethylene oxide or propylene oxide adducts thereof, trimethylolpropane Examples include epoxy acrylates derived from glycidyl ethers such as triglycidyl ether, melamine acrylates, and/or methacrylates corresponding to the above acrylates. Among these, polyvalent acrylates or polyvalent methacrylates are preferable, and examples of trivalent acrylates or methacrylates include trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and trimethylolpropane. EO-added tri(meth)acrylate, glycerin PO-added tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, tetrafurfuryl alcohol oligo(meth)acrylate, ethylcarbitol 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, dipentaerythritol hexa(meth) ) Acrylate, (meth)acrylic acid ester of N,N,N′,N′-tetrakis(β-hydroxyethyl)ethyldiamine, and the like, and tri(2- or higher) acrylates or methacrylates are tri(2- (Meth)acryloyloxyethyl)phosphate, tri(2-(meth)acryloyloxypropyl)phosphate, tri(3-(meth)acryloyloxypropyl)phosphate, tri(3-(meth)acryloyl-2-hydroxyloxypropyl) Phosphate, di(3-(meth)acryloyl-2-hydroxyloxypropyl)(2-(meth)acryloyloxyethyl)phosphate, (3-(meth)acryloyl-2-hydroxyloxypropyl)di(2-(meth)) Mention may be made of phosphoric acid triester (meth)acrylates such as acryloyloxyethyl)phosphate. These photosensitive (meth)acrylate compounds may be used alone or in combination of two or more.

The content when the component (E) is blended is from the viewpoint of accelerating photocuring and suppressing stickiness when it is a cured product, when the total solid content of the photosensitive resin composition is 100% by mass. 1 mass% to 10 mass% is preferable, and 3 mass% to 8 mass% is more preferable.

<(F) Organic solvent>
The photosensitive resin composition may further contain (F) an organic solvent. By including the component (F), the viscosity of the varnish can be adjusted. Examples of the organic solvent (F) include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol and propylene glycol. Glycol ethers such as 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, ethyl diglycol acetate, Examples thereof include aliphatic hydrocarbons such as octane and decane, petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. These may be used alone or in combination of two or more. When the organic solvent is used, the content thereof can be appropriately adjusted from the viewpoint of coatability of the photosensitive resin composition.

<(G) Other additives>
The photosensitive resin composition may further contain (G) and other additives to the extent that the object of the present invention is not impaired. (G) Other additives include, for example, fine particles of thermoplastic resin, organic filler, melamine, organic bentonite, phthalocyanine blue, phthalocyanine green, iodin green, diazo yellow, crystal violet, titanium oxide, carbon black, Colorants such as naphthalene black, hydroquinone, phenothiazine, methylhydroquinone, hydroquinone monomethyl ether, catechol, polymerization inhibitors such as pyrogallol, Benton, thickeners such as montmorillonite, silicone-based, fluorine-based, vinyl resin-based defoaming agent, Brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, phosphorus compounds, flame retardants such as aromatic condensed phosphoric acid esters, halogen-containing condensed phosphoric acid esters, phenolic curing agents, cyanate ester curing agents, etc. Various additives such as a cured resin can be added.

In the photosensitive resin composition, the components (A) to (D) are mixed as essential components, the components (E) to (G) are appropriately mixed as optional components, and if necessary, three rolls, A resin varnish can be produced by kneading or stirring with a kneading means such as a ball mill, a bead mill, a sand mill or a stirring means such as a super mixer or a planetary mixer.

<Physical properties and applications of photosensitive resin composition>
Since the photosensitive resin composition of the present invention contains the component (A) and the component (C) even if a large amount of the component (B) having a large average particle size is used, it exhibits excellent resolution. Therefore, there is no residue such as resin in the unexposed area. Further, because of excellent resolution, there is usually no resin embedding or peeling between L/S (line/space). The minimum opening via diameter without residue is preferably 100 μm or less, more preferably 90 μm or less, and further preferably 80 μm or less. The lower limit is not particularly limited, but may be 1 μm or more. The resolution can be evaluated according to the method described in <Evaluation of resolution, crack resistance and undercut resistance> described later.

A cured product obtained by photocuring the photosensitive resin composition of the present invention and then thermally curing it at 190° C. for 90 minutes exhibits a characteristic that the average linear thermal expansion coefficient is low. That is, it provides an insulating layer and a solder resist having a low average coefficient of linear thermal expansion. The average linear thermal expansion coefficient is preferably 45 ppm or less, more preferably 40 ppm or less, further preferably 36 ppm or less, 35 ppm or less. The lower limit is not particularly limited, but may be 10 ppm or more. The average linear thermal expansion coefficient can be measured according to the method described in <Measurement of average linear thermal expansion coefficient and glass transition temperature> described later.

A cured product obtained by photocuring the photosensitive resin composition of the present invention and then thermally curing it at 190° C. for 90 minutes shows a characteristic that the glass transition temperature is high. That is, it provides an insulating layer and a solder resist having a high glass transition temperature. The glass transition temperature is preferably 160° C. or higher, more preferably 170° C. or higher, still more preferably 180° C. or higher. The upper limit is not particularly limited, but may be 300° C. or lower. The glass transition temperature can be measured according to the method described in <Measurement of average linear thermal expansion coefficient and glass transition temperature> described later.

A cured product obtained by photocuring the photosensitive resin composition of the present invention and then thermally curing it at 190° C. for 90 minutes exhibits excellent undercut resistance. That is, an insulating layer and a solder resist having excellent undercut resistance are provided. The undercut is preferably 5 μm or less, more preferably 4 μm or less, still more preferably 3 μm or less. The lower limit is not particularly limited, but may be 0.1 μm or more. The undercut can be measured according to the method described in <Evaluation of resolution, crack resistance, and undercut resistance> described later.

A cured product obtained by photocuring the photosensitive resin composition of the present invention and then thermally curing it at 190° C. for 90 minutes exhibits excellent crack resistance. That is, an insulating layer and a solder resist having excellent crack resistance are provided. Even when the temperature rising test between −65° C. and 150° C. is repeated 500 times, no crack or peeling is observed. The crack resistance can be evaluated according to the method described in <Evaluation of resolution, crack resistance, and undercut resistance> described later.

The use of the photosensitive resin composition of the present invention is not particularly limited, a photosensitive film, a photosensitive film with a support, an insulating resin sheet such as prepreg, a circuit board (use as a laminate, use as a multilayer printed wiring board, etc.), It can be used in a wide range of applications where a photosensitive resin composition is required, such as a solder resist, an underfill material, a die bonding material, a semiconductor encapsulating material, a hole filling resin, and a component filling resin. Among them, a photosensitive resin composition for an insulating layer of a printed wiring board (a printed wiring board having a cured product of the photosensitive resin composition as an insulating layer), a photosensitive resin composition for an interlayer insulating layer (a photosensitive resin composition A printed wiring board having a cured product as an interlayer insulating layer), a photosensitive resin composition for forming a plating (a printed wiring board having a cured product of the photosensitive resin composition and plating formed thereon), and a photosensitive resin composition for a solder resist (Printed wiring board using a cured product of a photosensitive resin composition as a solder resist) can be suitably used.

[Photosensitive film]
The photosensitive resin composition of the present invention can be applied to a supporting substrate in a resin varnish state and dried with an organic solvent to form a photosensitive resin composition layer to form a photosensitive film. Further, a photosensitive film previously formed on a support can be laminated on a support substrate and used. The photosensitive film can be laminated on various supporting substrates. Examples of the supporting substrate include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates.

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

Examples of the support include polyethylene terephthalate film, polyethylene naphthalate film, polypropylene film, polyethylene film, polyvinyl alcohol film, triacetyl acetate film, and the like, and polyethylene terephthalate film is particularly preferable.

Examples of commercially available supports include product names “Alfan MA-410” and “E-200C” manufactured by Oji Paper Co., Ltd., polypropylene films manufactured by Shin-Etsu Film Co., Ltd., and product name “PS-25” manufactured by Teijin Ltd. Examples thereof include polyethylene terephthalate films such as PS series, but are not limited to these. In order to facilitate the removal of the photosensitive resin composition layer, these supports are preferably coated on the surface with a release agent such as a silicone coating agent. The thickness of the support is preferably in the range of 5 μm to 50 μm, more preferably 10 μm to 25 μm. By setting the thickness to 5 μm or more, it is possible to prevent the support from breaking at the time of peeling the support before development, and by setting the thickness to 50 μm or less, it is possible to prevent exposure from above the support. The resolution can be improved. Also, a low fish eye support is preferred. Here, the fish eye means that when a material is heat-melted, kneaded, extruded, biaxially stretched, or cast to produce a film, foreign matter, undissolved material, oxidative deterioration material, etc. are taken into the film. It is a thing.

Further, in order to reduce scattering of light at the time of exposure due to active energy rays such as ultraviolet rays, it is preferable that the support has excellent transparency. Specifically, the support preferably has a turbidity (haze standardized in JIS K6714) that is an index of transparency of 0.1 to 5. Further, the photosensitive resin composition layer may be protected by a protective film.

By protecting the photosensitive resin composition layer side of the photosensitive film with a support with a protective film, it is possible to prevent dust and the like from adhering to the surface of the photosensitive resin composition layer or scratches. As the protective film, a film made of the same material as the above support can be used. Although the thickness of the protective film is not particularly limited, it is preferably in the range of 1 μm to 40 μm, more preferably in the range of 5 μm to 30 μm, and further preferably in the range of 10 μm to 30 μm. When the thickness is 1 μm or more, the handleability of the protective film can be improved, and when the thickness is 40 μm or less, the cost tends to be improved. The protective film preferably has a smaller adhesive force between the photosensitive resin composition layer and the protective film than the adhesive force between the photosensitive resin composition layer and the support.

The photosensitive film with a support of the present invention is prepared according to a method known to those skilled in the art, for example, by preparing a resin varnish in which the photosensitive resin composition of the present invention is dissolved in an organic solvent, and coating the resin varnish on the support. Then, the organic solvent is dried by heating or blowing hot air to form the photosensitive resin composition layer. Specifically, first, after completely removing the bubbles in the photosensitive resin composition by a vacuum defoaming method or the like, the photosensitive resin composition is applied on a support, and the solvent is removed by a hot air oven or a far infrared oven. The support-containing photosensitive film can be produced by removing and drying, and then optionally laminating a protective film on the photosensitive resin composition layer obtained. The specific drying conditions vary depending on the curability of the photosensitive resin composition and the amount of organic solvent in the resin varnish, but in the resin varnish containing 30% by mass to 60% by mass of the organic solvent, 80°C to 120°C. Can be dried in 3 to 13 minutes. The amount of the residual organic solvent in the photosensitive resin composition layer is preferably 5% by mass or less with respect to the total amount of the photosensitive resin composition layer from the viewpoint of preventing the diffusion of the organic solvent in the subsequent step, It is more preferable that the amount is 2% by mass or less. Those skilled in the art can appropriately set suitable drying conditions by a simple experiment. The thickness of the photosensitive resin composition layer is preferably in the range of 5 μm to 500 μm from the viewpoints of improving handleability and suppressing deterioration of sensitivity and resolution inside the photosensitive resin composition layer. The range of 10 μm to 200 μm is more preferable, the range of 15 μm to 150 μm is more preferable, the range of 20 μm to 100 μm is still more preferable, and the range of 20 μm to 60 μm is particularly preferable.

The coating method of the photosensitive resin composition, for example, gravure coating method, microgravure coating method, reverse coating method, kiss reverse coating method, die coating method, slot die method, lip coating method, comma coating method, blade coating method, Examples thereof include a roll coating method, a knife coating method, a curtain coating method, a chamber gravure coating method, a slot orifice method, a spray coating method and a dip coating method.
The photosensitive resin composition may be applied several times, may be applied once, or may be applied by combining a plurality of different methods. Among them, the die coating method, which is excellent in uniform coatability, is preferable. Further, in order to prevent foreign matter from entering, it is preferable to carry out the coating step in an environment such as a clean room where few foreign matter is generated.

[Printed wiring board]
The printed wiring board of the present invention includes an insulating layer formed of a cured product of the photosensitive resin composition of the present invention. The insulating layer is preferably used as a solder resist.

Specifically, the printed wiring board of the present invention can be manufactured using the above-mentioned photosensitive film or the photosensitive film with a support. Hereinafter, a case where the insulating layer is a solder resist will be described.

<Coating and drying process>
The photosensitive resin composition is directly applied in a resin varnish state onto the circuit board, and the organic solvent is dried to form a photosensitive film on the circuit board.

Examples of the circuit board include a glass epoxy board, a metal board, a polyester board, a polyimide board, a BT resin board, and a thermosetting polyphenylene ether board. Here, the circuit board means a board on which a patterned conductor layer (circuit) is formed on one side or both sides of the board as described above. Also, in a multilayer printed wiring board in which conductor layers and insulating layers are alternately laminated, a substrate in which one or both outermost layers of the multilayer printed wiring board is a patterned conductor layer (circuit) is also used. It is included in the circuit board. The surface of the conductor layer may be preliminarily roughened by blackening treatment, copper etching or the like.

As the coating method, full-screen printing by a screen printing method is generally used, but any means may be used as long as it is a coating method capable of uniformly coating. For example, spray coating method, hot melt coating method, bar coating method, applicator method, blade coating method, knife coating method, air knife coating method, curtain flow coating method, roll coating method, gravure coating method, offset printing method, dip coating method , Brush coating, and other usual coating methods can all be used. After coating, if necessary, it is dried in a hot air oven or a far infrared oven. The drying condition is preferably 80° C. to 120° C. for 3 minutes to 13 minutes. In this way, the photosensitive film is formed on the circuit board.

<Laminating process>
When a photosensitive film with a support is used, the photosensitive resin composition layer side is laminated on one side or both sides of the circuit board using a vacuum laminator. In the laminating step, when the photosensitive film with a support has a protective film, the protective film is removed, and then the photosensitive film with a support and the circuit board are preheated as necessary to form a photosensitive resin composition. The physical layer is pressed onto the circuit board while being pressed and heated. For the photosensitive film with a support, a method of laminating on a circuit board under reduced pressure by a vacuum laminating method is preferably used.

The conditions of the laminating step are not particularly limited, but for example, the pressure bonding temperature (lamination temperature) is preferably 70° C. to 140° C., and the pressure bonding pressure is preferably 1 kgf/cm ^{2 to} 11 kgf/cm ² (9. 8×10 ⁴ N/m ^{2 to} 107.9×10 ⁴ N/m ² ), pressure bonding time is preferably 5 seconds to 300 seconds, and air pressure is 20 mmHg (26.7 hPa) or less. Is preferred. Further, the laminating step may be a batch type or a continuous type using a roll. The vacuum laminating method can be performed using a commercially available vacuum laminator. Examples of commercially available vacuum laminator include, for example, vacuum applicator manufactured by Nikko Materials Co., vacuum press type laminator manufactured by Meiki Seisakusho, roll dry coater manufactured by Hitachi Industries, vacuum laminator manufactured by Hitachi AIC Co. be able to. In this way, the photosensitive film is formed on the circuit board.

<Exposure process>
After a photosensitive film is provided on the circuit board by a coating and drying step or a laminating step, then, a predetermined portion of the photosensitive resin composition layer is irradiated with an actinic ray through a mask pattern, and the photosensitive portion of the irradiated portion is exposed to light. An exposure step of photo-curing the resin composition layer is performed. Examples of actinic rays include ultraviolet rays, visible rays, electron beams, and X-rays, and ultraviolet rays are particularly preferable. Dose of ultraviolet light is approximately ^{10mJ / cm 2 ~1000mJ / cm 2} . As the exposure method, there are a contact exposure method in which a mask pattern is brought into close contact with a printed wiring board and a non-contact exposure method in which parallel rays are used for exposure without making close contact, but either may be used. Further, when the support is present on the photosensitive resin composition layer, the exposure may be carried out from the support or may be carried out after the support is peeled off.

The solder resist is excellent in resolution because it uses the photosensitive resin composition of the present invention. Therefore, as the exposure pattern in the mask pattern, for example, the ratio (L/S) of the circuit width (line; L) and the width between the circuits (space; S) is 100 μm/100 μm or less (that is, the wiring pitch is 200 μm or less). , L/S=80 μm/80 μm or less (wiring pitch 160 μm or less), L/S=70 μm/70 μm or less (wiring pitch 140 μm or less), L/S=60 μm/60 μm or less (wiring pitch 120 μm or less) can be used Is. Note that the pitch does not have to be the same over the entire circuit board.

<Developing process>
After the exposure process, if a support is present on the photosensitive resin composition layer, the support is removed, and then the non-photocured part (unexposed part) is removed by wet development or dry development. Then, a pattern can be formed by developing.

In the case of the above-mentioned wet development, as the developing solution, a developing solution which is safe and stable and has good operability, such as an alkaline aqueous solution, an aqueous developing solution or an organic solvent, is used. Among them, a developing step using an alkaline aqueous solution is preferable. Further, as a developing method, a known method such as spraying, rocking dipping, brushing, scraping, etc. is appropriately adopted.

Examples of the alkaline aqueous solution used as the developer include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide and potassium hydroxide, carbonates or bicarbonates such as sodium carbonate and sodium bicarbonate, sodium phosphate. , Alkali metal phosphates such as potassium phosphate, sodium pyrophosphate, aqueous solutions of alkali metal pyrophosphates such as potassium pyrophosphate, and aqueous solutions of organic bases containing no metal ions such as tetraalkylammonium hydroxide, An aqueous solution of tetramethylammonium hydroxide (TMAH) is preferable because it does not contain metal ions and does not affect the semiconductor chip.
To these alkaline aqueous solutions, a surfactant, a defoaming agent or the like can be added to the developing solution in order to improve the developing effect. The pH of the alkaline aqueous solution is preferably, for example, in the range of 8 to 12, and more preferably in the range of 9 to 11. The base concentration of the alkaline aqueous solution is preferably 0.1% by mass to 10% by mass. The temperature of the alkaline aqueous solution can be appropriately selected depending on the developability of the photosensitive resin composition layer, but is preferably 20°C to 50°C.

Examples of the organic solvent used as the developing solution include acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol. It is monobutyl ether.

The concentration of such an organic solvent is preferably 2% by mass to 90% by mass with respect to the total amount of the developing solution. Further, the temperature of such an organic solvent can be adjusted according to the developability. Further, such organic solvents can be used alone or in combination of two or more kinds. Examples of the organic solvent-based developer used alone include 1,1,1-trichloroethane, N-methylpyrrolidone, N,N-dimethylformamide, cyclohexanone, methyl isobutyl ketone and γ-butyrolactone.

In pattern formation, two or more types of developing methods described above may be used in combination, if necessary. Development methods include a dip method, a battle method, a spray method, a high-pressure spray method, brushing, and slapping, and the high-pressure spray method is suitable for improving resolution. When using the spray method, the spray pressure is preferably 0.05 MPa to 0.3 MPa.

<Thermosetting (post bake) process>
After the development process is completed, a thermosetting (post-baking) process is performed to form a solder resist. Examples of the post-baking process include an ultraviolet irradiation process using a high pressure mercury lamp and a heating process using a clean oven. When the ultraviolet rays are irradiated, the irradiation amount can be adjusted as necessary, and the irradiation can be performed with an irradiation amount of, for example, about 0.05 J/cm ^{2 to} 10 J/cm ² . The heating conditions may be appropriately selected depending on the type and content of the resin component in the photosensitive resin composition, but are preferably in the range of 150°C to 220°C for 20 minutes to 180 minutes, more preferably It is selected in the range of 160°C to 200°C for 30 minutes to 120 minutes.

<Other processes>
The printed wiring board may further include a drilling step and a desmearing step after forming the solder resist. These steps may be carried out according to various methods known to those skilled in the art for manufacturing printed wiring boards.

After the solder resist is formed, a hole is formed in the solder resist formed on the circuit board to form via holes and through holes, if desired. The drilling step can be carried out, for example, by a known method such as drilling, laser, plasma or the like, and if necessary, these methods may be combined, but a drilling step by a laser such as a carbon dioxide laser or a YAG laser is preferable.

The desmear process is a process of performing a desmear process. A resin residue (smear) is generally attached inside the opening formed in the drilling step. Since such smear causes a poor electrical connection, a process for removing smear (desmear process) is performed in this step.

The desmear treatment may be performed by a dry desmear treatment, a wet desmear treatment, or a combination thereof.

Examples of the dry desmear treatment include a desmear treatment using plasma. The desmear processing using plasma can be implemented using a commercially available plasma desmear processing apparatus. Among commercially available plasma desmear processing devices, examples suitable for manufacturing printed wiring boards include a microwave plasma device manufactured by Nissin and an atmospheric pressure plasma etching device manufactured by Sekisui Chemical Co., Ltd.

Examples of the wet desmear treatment include desmear treatment using an oxidant solution. When the desmear treatment is performed using the oxidant solution, it is preferable to perform the swelling treatment with the swelling solution, the oxidation treatment with the oxidant solution, and the neutralization treatment with the neutralizing solution in this order. Examples of the swelling liquid include “Swelling Dip Securigans P” and “Swelling Dip Securigans SBU” manufactured by Atotech Japan. The swelling treatment is preferably performed by immersing the substrate having the via holes and the like in a swelling liquid heated to 60° C. to 80° C. for 5 minutes to 10 minutes. The oxidant solution is preferably an aqueous alkaline permanganate solution, and examples thereof include a solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The oxidation treatment with the oxidizing agent solution is preferably performed by immersing the substrate after the swelling treatment in the oxidizing agent solution heated to 60°C to 80°C for 10 minutes to 30 minutes. Examples of commercially available alkaline permanganate aqueous solutions include "Concentrate Compact CP" and "Dosing Solution Securigans P" manufactured by Atotech Japan. The neutralization treatment with the neutralization liquid is preferably performed by immersing the substrate after the oxidation treatment in the neutralization liquid at 30°C to 50°C for 3 minutes to 10 minutes. The neutralizing solution is preferably an acidic aqueous solution, and examples of the commercially available product include "Reduction Solution Securigant P" manufactured by Atotech Japan.

When the dry desmear treatment and the wet desmear treatment are performed in combination, the dry desmear treatment may be performed first or the wet desmear treatment may be performed first.

When the insulating layer is used as the interlayer insulating layer, it can be performed in the same manner as in the case of the solder resist, and the hole forming step, the desmear step, and the plating step may be performed after the thermosetting step.

The plating step is a step of forming a conductor layer on the insulating layer. The conductor layer may be formed by combining electroless plating and electroplating, or a plating resist having a pattern opposite to that of the conductor layer may be formed and the conductor layer may be formed only by electroless plating. As a method for forming the pattern thereafter, for example, a subtractive method, a semi-additive method or the like known to those skilled in the art can be used.

[Semiconductor device]
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.

Examples of the semiconductor device include various semiconductor devices provided for electric products (for example, computers, mobile phones, digital cameras and televisions) and vehicles (for example, motorcycles, automobiles, trains, ships and aircrafts).

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. The "conducting portion" is "a portion of the printed wiring board for transmitting an electric signal", and the location may be a surface or an embedded portion. The semiconductor chip is not particularly limited as long as it is an electric circuit element made of a semiconductor.

The semiconductor chip mounting method for manufacturing the semiconductor device of the present invention is not particularly limited as long as the semiconductor chip functions effectively. Specifically, the wire bonding mounting method, the flip chip mounting method, and the bumpless method are used. Examples include a mounting method using a build-up layer (BBUL), a mounting method using an anisotropic conductive film (ACF), and a mounting method using a non-conductive film (NCF). Here, the "mounting method using a bump-free build-up layer (BBUL)" means "a mounting method in which a semiconductor chip is directly embedded in a recess of a printed wiring board to connect the semiconductor chip and wiring on the printed wiring board". Is.

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In the following description, “parts” and “%” representing amounts mean “parts by mass” and “mass %”, respectively, unless otherwise specified.

(Synthesis Example 1: Synthesis of Resin (A-1))
162 parts of 1,1′-bis(2,7-diglycidyloxynaphthyl)methane (“EXA-4700”, manufactured by Dainippon Ink and Chemicals, Inc.) having an epoxy equivalent of 162, a gas introduction pipe, a stirring device, and a cooling pipe. Then, 340 parts of carbitol acetate was added to a flask equipped with a thermometer and dissolved by heating, 0.46 parts of hydroquinone and 1 part of triphenylphosphine were added. This mixture was heated to 95 to 105° C., 72 parts of acrylic acid was gradually added dropwise, and the mixture was reacted for 16 hours. The reaction product was cooled to 80 to 90° C., 80 parts of tetrahydrophthalic anhydride was added, and the mixture was reacted for 8 hours and cooled. Thus, a resin solution having a solid acid value of 90 mgKOH/g (nonvolatile content 70%, hereinafter abbreviated as "A-1") was obtained.

<Examples 1 to 5, Comparative Examples 1 to 6>
The respective components were blended in the blending ratios shown in the following table, and a resin varnish was prepared using a high speed rotary mixer. Next, a PET film (“Lumirror T6AM” manufactured by Toray Industries, Inc., thickness: 38 μm, softening point: 130° C.) released from an alkyd resin-based release agent (“AL-5” manufactured by Lintec Co., Ltd.) as a support, “release PET” ]) was prepared. By applying the prepared resin varnish to such a release PET uniformly by a die coater so that the thickness of the photosensitive resin composition layer after drying becomes 40 μm, and drying at 80° C. to 110° C. for 6.5 minutes. A photosensitive film with a support having a photosensitive resin composition layer on the release PET was obtained.

The measurement method and evaluation method in the physical property evaluation will be described.

<Evaluation of resolution, crack resistance, and undercut resistance>
(Formation of evaluation laminate)
Roughening of the copper layer of a glass epoxy substrate (copper-clad laminate) on which a circuit is formed by patterning a copper layer having a thickness of 18 μm by treatment with a surface treatment agent (CZ8100, manufactured by MEC Co.) containing an organic acid. Was applied. Next, the photosensitive resin composition layer of the photosensitive film with a support obtained in each of Examples and Comparative Examples was placed so as to be in contact with the copper circuit surface, and a vacuum laminator (VP160, manufactured by Nikko Materials Co., Ltd.) was used. By laminating, the copper clad laminate, the photosensitive resin composition layer, and the support were laminated in this order to form a laminate. The pressure bonding conditions were a vacuuming time of 30 seconds, a pressure bonding temperature of 80° C., a pressure bonding pressure of 0.7 MPa, and a pressure time of 30 seconds. The laminate was allowed to stand at room temperature for 30 minutes or longer, and exposed to ultraviolet rays from above the support of the laminate using a pattern forming apparatus using a round hole pattern. The exposure pattern has openings: 50 μm/60 μm/70 μm/80 μm/90 μm/100 μm round holes, L/S (line/space): 50 μm/50 μm, 60 μm/60 μm, 70 μm/80 μm/80 μm, 90 μm/90 μm, 100 μm A quartz glass mask for drawing a line/space of /100 μm and a square of 1 cm×2 cm was used. After standing at room temperature for 30 minutes, the support was peeled off from the laminate. A 1% by mass sodium carbonate aqueous solution at 30° C. as a developer was spray-developed for 2 minutes on the entire surface of the photosensitive resin composition layer on the laminated plate at a spray pressure of 0.2 MPa. After spray development, irradiation with 1 J/cm ² of ultraviolet rays was performed, and heat treatment was further performed at 180° C. for 30 minutes to form an insulating layer having an opening on the laminate. This was used as an evaluation laminate.

(Evaluation of resolution)
The unexposed portion of the 1 cm×2 cm portion of the evaluation laminate was visually observed. When the resin did not remain in the unexposed area, it was rated as ◯, and when the resin could be visually confirmed, it was rated as x. Next, the formed via and L/S were observed by SEM (magnification: 1000 times), and the minimum via diameter without residue and the minimum L/S were measured. The L/S shape was evaluated according to the following criteria.
◯: Three points of L/S were observed and there was no peeling or filling between all L/S.
X: Three points of L/S were observed, and resin embedding or peeling was observed between any of the L/S.

(Crack resistance evaluation)
The laminate for evaluation was exposed to the atmosphere of −65° C. for 15 minutes, then heated at a temperature increase rate of 180° C./minute, and then exposed to the atmosphere of 175° C. for 15 minutes, and then 180° C./minute. The test was repeated 500 times by the heat cycle in which the temperature was lowered at the temperature lowering rate. After the test, the degree of cracking and peeling of the evaluation laminate was observed with an optical microscope ("ECLIPSE LV100ND" manufactured by Nikon Corporation), and evaluated according to the following criteria.
◯: No crack or peeling observed.
X: Cracks and peeling are recognized.

(Evaluation of undercut resistance)
A 100 μm via formed by the evaluation laminate was subjected to SEM cross-section observation, and the radius (a (μm)) of the top and the radius (b (μm)) of the bottom of the cross-section were measured, and the difference between them was obtained.

<Measurement of average linear thermal expansion coefficient and glass transition temperature>
(Formation of cured product for evaluation)
The photosensitive resin composition layer of the photosensitive film with a support obtained in each of Examples and Comparative Examples was exposed to ultraviolet light of 100 mJ/cm ² and photocured. Thereafter, a 1% by mass sodium carbonate aqueous solution at 30° C. as a developer was spray-developed for 2 minutes on the entire surface of the photosensitive resin composition layer at a spray pressure of 0.2 MPa. After spray development, irradiation with 1 J/cm ² of ultraviolet rays was performed, and heat treatment was further performed at 190° C. for 90 minutes to form a cured product. Then, the support was peeled off to obtain a cured product for evaluation.

(Measurement of average linear thermal expansion coefficient)
The cured product for evaluation was cut into a test piece having a width of 5 mm and a length of 15 mm, and thermomechanical analysis was performed by a tensile load method using a thermomechanical analyzer (Thermo Plus TMA8310, manufactured by Rigaku Corporation). After mounting the test piece on the apparatus, measurement was performed twice continuously under the measurement conditions of a load of 1 g and a heating rate of 5° C./min. The average linear thermal expansion coefficient (ppm) from 25° C. to 150° C. in the second measurement was calculated.

(Measurement of glass transition temperature)
The cured product for evaluation was cut into a test piece having a width of about 5 mm and a length of about 15 mm, and thermomechanical analysis was carried out by a tensile load method using a dynamic viscoelasticity measuring device (EXSTAR6000, manufactured by SII Nanotechnology Inc.). .. After mounting the test piece on the apparatus, the load was 200 mN and the temperature rising rate was 2° C./min. The peak top of the obtained tan δ was calculated as the glass transition temperature (°C).

The resins used are as follows.
Component (A)-ZFR-1491H: Bisphenol F type epoxy acrylate (manufactured by Nippon Kayaku Co., acid value 99 mgKOH/g, solid concentration about 70%).
ZAR-2000: Bisphenol A type epoxy acrylate (manufactured by Nippon Kayaku Co., acid value 99 mg KOH/g, solid content concentration about 70%)
ZCR-1569H: Biphenyl type epoxy acrylate (manufactured by Nippon Kayaku Co., acid value 98 mgKOH/g, solid content concentration about 70%)
A-1: Resin (A-1) synthesized in Synthesis Example 1
Component (B)-SC4050: Surface-treated with 0.5 parts by mass of aminosilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM573) with respect to 100 parts by mass of fused silica (manufactured by Admatex, average particle size 1.0 μm) (C) Ingredient Irgacure 379: 2-dimethylamino-2-(4-methyl-benzyl-1-(4-morpholin-4-yl-phenyl)-butan-1-one) (manufactured by BASF).
-Irgacure 907: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one) (manufactured by BASF)
DETX-S: photopolymerization initiation aid (2-4-diethylthioxanthone, manufactured by Nippon Kayaku Co., Ltd.)
IrgacureTPO: bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide) (manufactured by BASF)
-Irgacure 819: bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide) (manufactured by BASF)
-Irgacure OXE-01: 1,2-octanedione-1-[4-(phenylthio)-2-(O-benzoyloxime)] (manufactured by BASF)
Component (D)-NC3000H: Biphenyl type epoxy resin (Nippon Kayaku Co., Ltd., epoxy equivalent: 272)
1031S: tetrakishydroxyphenylethane type epoxy resin (Mitsubishi Chemical Co., epoxy equivalent 200)
(E) component-DPHA: dipentaerythritol hexaacrylate (Nippon Kayaku Co., acrylic equivalent of about 96)
Content of component (B): content of component (B) when the total solid content of the photosensitive resin composition is 100% by mass.

From the results in the above table, in the examples using the photosensitive resin composition of the present invention, good developability, undercut resistance, has crack resistance, low average linear thermal expansion coefficient, and high glass transition temperature I understood.

On the other hand, in Comparative Examples 1 to 3, since the component (C) was not used, the undercut resistance was poor and it could not be used as a photosensitive resin composition. In Comparative Examples 4 to 6, since the component (A) was not used, the developability and crack resistance were poor, the average coefficient of linear thermal expansion was high, the glass transition temperature was low, and it could not be used as a photosensitive resin composition. It was In Comparative Example 4, the undercut resistance could not be evaluated because the developability was considerably poor.

In each of the examples, it was confirmed that even when the component (E) or the like was not contained, the same results as those of the above-mentioned examples were obtained although there were some differences.

Claims (11)

(A) a resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group,
(B) an inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less,
A photosensitive resin composition containing (C) an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator, and (D) an epoxy resin,
The content of the component (B) is 60% by mass or more and 85% by mass or less when the total solid content of the photosensitive resin composition is 100% by mass, and 190 after photocuring the photosensitive resin composition. A photosensitive resin composition having a glass transition temperature of 170° C. or higher, which is obtained by thermosetting at 90° C. for 90 minutes. The photosensitive resin composition according to claim 1, wherein the component (A) contains an acid-modified naphthalene skeleton-containing epoxy (meth)acrylate. (A) a resin containing a naphthalene skeleton, an ethylenically unsaturated group, and a carboxyl group,
(B) an inorganic filler having an average particle size of 0.5 μm or more and 2.5 μm or less,
A photosensitive resin composition containing (C) an acylphosphine oxide photopolymerization initiator or an oxime ester photopolymerization initiator, and (D) an epoxy resin,
The content of the component (B) is 60% by mass or more and 85% by mass or less when the total solid content of the photosensitive resin composition is 100% by mass, and the component (A) is
(1) 1,3-diglycidyloxynaphthalene, 1,4-diglycidyloxynaphthalene, 1,5-diglycidyloxynaphthalene, 1,6-diglycidyloxynaphthalene, 2,3-diglycidyloxynaphthalene, 2, 6-diglycidyloxynaphthalene and 2,7-diglycidyloxynaphthalene;
(2) Polyhydroxybinaphthalene type epoxy resin;
(3) A naphthalene-type epoxy resin having a skeleton obtained by a condensation reaction of polyhydroxynaphthalene and aldehydes; and (4) at least one naphthalene-type epoxy compound selected from a binaphthol-type epoxy resin is reacted with an unsaturated carboxylic acid. A photosensitive resin composition comprising an acid-modified unsaturated naphthalene skeleton-containing epoxy ester resin obtained by further reacting with an acid anhydride. The component (C) is bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, and 1,2-octanedione-1-. The photosensitive resin composition according to any one of claims 1 to 3, which is any one of [4-(phenylthio)-2-(O-benzoyloxime)]. The photosensitive resin composition according to any one of claims 1 to 4, wherein the component (D) includes at least one of a biphenyl type epoxy resin and a tetraphenylethane type epoxy resin. The photosensitive resin composition according to any one of claims 1 to 5, wherein the component (B) contains silica. Containing photosensitive resin composition according to any one of claims 1 to 6 photosensitive film. A photosensitive film with a support, comprising: a support; and a photosensitive resin composition layer, which is provided on the support and contains the photosensitive resin composition according to any one of claims 1 to 7 . Printed circuit board containing the formed insulating layer with a cured product of the photosensitive resin composition according to any one of claims 1-6. The printed wiring board according to claim 9 , wherein the insulating layer is a solder resist. To claim 9 or 1 0 includes a printed wiring board according semiconductor device.