WO2020027024A1

WO2020027024A1 - Photosensitive resin composition, plating method, and method for producing metal pattern

Info

Publication number: WO2020027024A1
Application number: PCT/JP2019/029588
Authority: WO
Inventors: 宗利入澤; 優子中村; 旭伊藤; 邦人梶谷
Original assignee: 三菱製紙株式会社
Priority date: 2018-08-02
Filing date: 2019-07-29
Publication date: 2020-02-06
Also published as: JP7392061B2; CN112470075A; KR20210038554A; JP7268028B2; JP2022169628A; TW202012452A; JPWO2020027024A1

Abstract

The present invention addresses the problem of providing the following: a photosensitive resin composition which exhibits high resolution, with which peeling of a resist is easy even in a narrow pitch resist pattern, and with which ultrafine lines and dots are stably held on a base material in a pattern forming step or plating step; and a plating method that uses this photosensitive resin composition. The problem is solved by: a photosensitive resin composition which contains (A) an alkali-soluble resin, (B) a photopolymerization initiator and (C) an acrylate monomer, and in which the content of a methacrylate monomer (D) is 0-5 mass% relative to the acrylate monomer (C), an ethylene oxide-modified pentaerythritol tetraacrylate (C1) (a compound which is represented by general formula (i) and in which l+m+n+o=24-48) is contained as the acrylate monomer (C), and the content of component (C1) relative to the total amount of component (C) is 30-70 mass%; and a plating method and method for producing a metal pattern in which the photosensitive resin composition is used.

Description

Photosensitive resin composition, plating method and method for producing metal pattern

The present invention relates to a photosensitive resin composition, a plating method using the photosensitive resin composition, and a method for producing a metal pattern.

In recent years, as electronic devices have become smaller and lighter, patterns on printed wiring boards, metal masks, and the like have been miniaturized. Therefore, in the production of a conductor circuit or a metal mask of a printed wiring board, a metal layer is produced by an additive method using a photosensitive resin composition and electrolytic plating.

For example, the (semi) additive method for printed wiring boards involves first forming a thin electroless plating layer on the surface of an insulating resin such as a glass epoxy resin by electroless plating, and then containing a photosensitive resin composition on the copper layer surface. After forming a photosensitive resin layer, then performing exposure and development to form a resist pattern, and then laminating a thick electrolytic plating layer by electrolytic plating, peeling off the resist pattern, electroless plating appeared after peeling This is a method of etching a layer (for example, Patent Document 1).

Further, for example, as a method of manufacturing a metal mask, a first step of forming a photosensitive resin layer containing a photosensitive resin composition having a predetermined thickness on a substrate, and an opening of the metal mask on the photosensitive resin layer A second step of pattern exposure according to the following, a third step of developing and removing a non-exposed portion of the photosensitive resin layer to form a resist pattern and exposing the substrate, and a step of exposing the substrate obtained in the third step. After performing a fourth step of forming a metal mask material layer on the exposed portion by electrolytic plating, a fifth step of removing the remaining photosensitive resin layer and a sixth step of separating the metal mask material layer from the substrate are performed. There is a manufacturing method (for example, Patent Document 2).

In these methods, a resist pattern having a narrow pitch is formed, electrolytic plating is performed between the narrow spaces, and a thick metal layer serving as an electrolytic plating layer or a metal mask material layer is formed. However, in the subsequent resist stripping step, which is a step of stripping the resist pattern or removing the remaining photosensitive resin layer, the resist pattern is not stripped normally, and the resist stripping pieces are formed on a printed wiring board or a metal mask. There is a problem that remains.

感光 In order to solve such a problem of resist stripping, a photosensitive resin composition having high adhesion to a base material and being dissolved in a resist stripping solution has been proposed (for example, see Patent Documents 3 to 6). If the solubility in the resist stripping solution is good, it is possible to eliminate the problem that resist strips remain in narrow spaces.

Patent Documents 3 to 6 disclose a photosensitive resin composition in which the content of a methacrylate monomer is reduced and the content of an acrylate monomer is increased as a crosslinkable monomer in order to increase the solubility of the photosensitive resin composition in a resist stripping solution. Things have been suggested. However, when the content of the acrylate monomer is increased, the hydrophilicity of the photosensitive resin composition is high, so that the photosensitive resin layer swells during alkali development. As a result, when the resist thickness is as large as 50 μm or more, 50 μm There are problems such as the following that it is difficult to resolve a narrow resist space, and a problem that fine lines and dots are easily peeled off from a substrate in a resist pattern formation and plating process.

Therefore, it has the property of dissolving in the resist stripping solution, and even in a resist pattern having fine lines and dots, it is stably held on the substrate in the pattern formation and plating process, and has a high resolution A resin composition is desired.

JP 2004-101617 A JP-A-4-166844 JP-A-9-265180 JP 2010-113349 A JP 2011-081031 A JP 2013-037272 A

An object of the present invention is to easily remove a resist even in a narrow-pitch resist pattern, and to stably hold fine lines and dots on a substrate in a pattern forming and plating process, and to have high resolution. An object of the present invention is to provide a photosensitive resin composition, a plating method using the photosensitive resin composition, and a method for producing a metal pattern.

結果 As a result of intensive studies to solve the above problems, the following means were found.

<1>
It contains (A) an alkali-soluble resin, (B) a photopolymerization initiator and (C) an acrylate monomer,
The content of the (D) methacrylate monomer is 0 to 5% by mass with respect to the (C) acrylate monomer,
(C) As an acrylate monomer, (C1) ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i) and having 1 + m + n + o = 24 to 48),
The content of (C1) ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), where l + m + n + o = 24 to 48) is 30 to 70% by mass based on the total amount of (C) acrylate monomer. A photosensitive resin composition comprising:

<2>
The photosensitive resin composition contains, as (C) an acrylate monomer, (C2) ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i), and 1 + m + n + o = 4 to 8); (1) The content of (C2) ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), where l + m + n + o = 4 to 8) is 30 to 70% by mass relative to the total amount of the acrylate monomer. > The photosensitive resin composition as described above.

<3>
The photosensitive resin composition contains (E) a polymerization inhibitor, and based on the total amount of (A) an alkali-soluble resin, (B) a photopolymerization initiator, (C) an acrylate monomer, and (E) a polymerization inhibitor. (E) The photosensitive resin composition according to <1>, wherein the content of the polymerization inhibitor is 400 to 1000 ppm.

<4>
The photosensitive resin composition contains (F) a photochromic agent, and (A) an alkali-soluble resin, (B) a photopolymerization initiator, (C) an acrylate monomer, and (F) a photochromic agent. F) The photosensitive resin composition according to <1>, wherein the content of the photochromic agent is 0.15 to 1.5% by mass.

<5>
A photosensitive resin layer containing the photosensitive resin composition according to any one of <1> to <4> is formed on a substrate, followed by pattern exposure to cure an exposed portion, and then alkali development. A plating method, which comprises removing a photosensitive resin layer in a non-exposed portion to form a resist pattern including a cured photosensitive resin layer, and then plating the exposed base material.

<6>
A method for producing a metal pattern, comprising forming a metal pattern on a substrate using the plating method according to <5>.

According to the present invention, even in a narrow-pitch resist pattern, the resist is easily peeled off, and fine lines and dots are stably held on the base material in the pattern forming and plating steps, and high resolution is achieved. The present invention can provide a photosensitive resin composition having the same, and a plating method using the photosensitive resin composition.
Further, according to the present invention, the resist is easily peeled off after the pattern is formed, and the resist pattern is stably held on the base material, so that fine lines and dots are formed on the base material in the plating step. And a metal pattern having high resolution can be formed.

Hereinafter, the photosensitive resin composition and the plating method of the present invention will be described in detail.

The photosensitive resin composition of the present invention contains (A) an alkali-soluble resin, (B) a photopolymerization initiator, and (C) an acrylate monomer, and contains (D) a methacrylate monomer with respect to (C) an acrylate monomer. (C1) an ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), wherein l + m + n + o = 24 to 48) as an (C) acrylate monomer, C) The content of (C1) ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), where l + m + n + o = 24 to 48) is 30 to 70% by mass relative to the total amount of the acrylate monomer. It is characterized by.

Ｌl, m, n and o in the general formula (i) are all the number of repeating units in the general formula (i), and are all natural numbers.

In the (A) alkali-soluble resin of the present invention, the term “alkali-soluble” means that a film of 0.01 μm or more is formed when a target resin is formed into a film and immersed in a 1% by mass aqueous sodium carbonate solution at 25 ° C. for 10 minutes. Refers to the dissolving property.
(A) The alkali-soluble resin is specifically a resin containing an acidic group, and includes a resin having an acid value of 40 mgKOH / g or more. Specific examples of the acidic group include a carboxyl group, a phenolic hydroxyl group, a sulfonic acid group, and a phosphoric acid group.

(A) Examples of the alkali-soluble resin include organic polymers such as (meth) acrylic resin, styrene resin, epoxy resin, amide resin, amide epoxy resin, alkyd resin, and phenol resin. . These may be used alone or in combination of two or more.

中でも Among them, it is preferable to use a (meth) acrylic resin. As the (meth) acrylic resin, a (meth) acrylic polymer obtained by copolymerizing an ethylenically unsaturated carboxylic acid with (meth) acrylate as a main component is preferable. Further, this may be obtained by copolymerizing another monomer having a copolymerizable ethylenically unsaturated group.

Examples of the (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, glycidyl (meth) Acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2- (dimethylamino) ethyl (meth) acrylate, 2- (diethylamino) ethyl (meth) acrylate, 2, , 2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate.
Note that, when described as “(meth) acrylic”, “(meth) acrylate”, etc., it means “acrylic or methacrylic”, “acrylate or methacrylate”, and the like, respectively.

As the ethylenically unsaturated carboxylic acid, acrylic acid, methacrylic acid, monocarboxylic acids such as crotonic acid are suitably used, maleic acid, fumaric acid, dicarboxylic acids such as itaconic acid, and anhydrides and half esters thereof. It can also be used. Among these, acrylic acid and methacrylic acid are particularly preferred.

Examples of the other copolymerizable monomers having an ethylenically unsaturated group include, for example, styrene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, p-methoxystyrene, p-ethoxystyrene, and p-chloro. Styrene, p-bromostyrene, (meth) acrylonitrile, (meth) acrylamide, diacetone acrylamide, vinyl toluene, vinyl acetate, vinyl-n-butyl ether, and the like.

(A) The acid value of the alkali-soluble resin affects the alkali developing speed, the resist peeling speed, the exposure sensitivity, the softness of the photosensitive resin layer, the adhesion between the photosensitive resin layer and the substrate, and the like. (A) The alkali-soluble resin preferably has an acid value of 40 to 500 mgKOH / g, more preferably 100 to 300 mgKOH / g.
If the acid value is less than 40 mgKOH / g, the alkali development time may be long, while if it exceeds 500 mgKOH / g, the adhesion between the photosensitive resin layer and the substrate may be poor. The acid value is a value measured according to JIS K2501: 2003.

(4) The weight average molecular weight of the alkali-soluble resin (A) is preferably from 5,000 to 150,000, more preferably from 10,000 to 100,000. (A) If the weight average molecular weight of the alkali-soluble resin is less than 5,000, it may be difficult to form the photosensitive resin composition before curing into a film state. On the other hand, when the weight average molecular weight of the alkali-soluble resin (A) exceeds 150,000, the solubility in an alkali developing solution may be deteriorated, or the rate of dissolution in a resist stripping solution may be slow.

(B) Examples of photopolymerization initiators include 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one and 2-methyl-1- [4- (methylthio) phenyl] -2 Aromatic ketones such as morpholino-propan-1-one; 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2-phenyl Anthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone Quinones such as benzoin methyl ether, benzoy Benzoin ether compounds such as ethyl ether and benzoin phenyl ether; benzoin compounds such as benzoin, methyl benzoin and ethyl benzoin; benzyl dimethyl ketal, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl- Propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- ( 2-hydroxy-2-methyl-propionyl) -benzyl] phenyl {-2-methyl-propan-1-one, 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- Alkylphenones such as (4-morpholinyl) phenyl] -1-butanone; 2,4,6- Acylphosphine oxides such as trimethylbenzoyl-diphenyl-phosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; 1,2-octanedione, 1- [4- (phenylthio)- Oximes, such as ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (o-acetyloxime) Esters; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-bis (methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) ) -4,5-Diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazo Dimer, 2,4,5-triarylimidazole dimer such as 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer; 9-phenylacridine, 1,7-bis ( Acridine derivatives such as 9,9'-acridinyl) heptane; N-phenylglycine, N-phenylglycine derivatives; coumarin compounds; benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone , 4-benzoyl-4'-methyldiphenylsulfide, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4,4'- Benzopheno such as bis (diethylamino) benzophenone System compounds.

The substituents of the aryl groups of the two 2,4,5-triarylimidazoles in the 2,4,5-triarylimidazole dimer may be identical or symmetric, or different. Asymmetric compounds may be provided. Further, a thioxanthone-based compound and a tertiary amine compound may be combined like a combination of diethylthioxanthone and dimethylaminobenzoic acid.
These are used alone or in combination of two or more. Among them, imidazole dimer has high sensitivity and can be suitably used, and 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer can be usefully used.

感光 The photosensitive resin composition of the present invention contains (C1) an ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i), where 1 + m + n + o = 24 to 48) as an acrylate monomer. By containing (C1), the swelling of the photosensitive resin layer cured during alkali development is small, while maintaining the property that the resist pieces dissolve during peeling of the resist, and the adhesion to the substrate is excellent. In addition, the effect of stably retaining fine lines and dots in the pattern formation and plating steps can be achieved.

If the value of (l + m + n + o) in (C1) is smaller than 24, the undercut (narrowing of the image line width at the bottom of the resist) may be large, and if the value of (l + m + n + o) is larger than 48, the photosensitivity in alkali development In some cases, the resin layer easily swells and a fine pattern cannot be formed. Therefore, the value of l + m + n + o in (C1) is from 24 to 48, and more preferably from 30 to 40.

The photosensitive resin composition of the present invention contains (C2) an ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i), wherein l + m + n + o = 4 to 8) as an acrylate monomer. Is preferred. By containing (C2), while maintaining the property that the resist strip is dissolved when the resist is stripped, the swelling of the photosensitive resin layer during alkali development is small and the adhesion to the substrate is excellent. More effective.

When the value of (l + m + n + o) in (C2) is smaller than 4, the undercut may increase. On the other hand, when the value of (l + m + n + o) is larger than 8, the photosensitive resin layer may be easily swelled by alkali development, resulting in a fine pattern. May not be formed. Therefore, the value of l + m + n + o of (C2) is 4 to 8, and more preferably 4.

(C) The acrylate monomer may contain “an acrylate monomer other than (C3), (C1) and (C2)”. (C3) includes a compound having one or more acryloyl groups.

Examples of (C3) having one acryloyl group include, for example, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, n-hexyl acrylate, 2-ethylhexyl Acrylate, cyclohexyl acrylate, benzyl acrylate, isomyristyl acrylate, stearyl acrylate, nonylphenoxy polyethylene glycol acrylate (at least one ethoxy group), 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, glycidyl acrylate, lauryl acrylate, tetrahydrofurfuryl acrylate , 2- (dimethylamino) ethyl acrylate, 2- (diethylamino) Ethyl acrylate, 2,2,2-trifluoroethyl acrylate, 2,2,3,3-tetrafluoropropyl acrylate, glycerin monoacrylate, methoxypolyethylene glycol acrylate (with 2 to 30 ethoxy groups), phenoxypolyethylene glycol acrylate (ethoxy Methoxypolypropylene glycol acrylate (2-30 propoxy groups), phenoxypolypropylene glycol acrylate (2-30 propoxy groups), 2-acryloyloxyethyl succinate, 2-hydroxy-3-phenoxypropyl acrylate And ethoxylated o-phenylphenol acrylate.
An “ethoxy group” is “—CH ₂ CH ₂ O—”. The “propoxy group” is “—C ₃ H ₆ O—”, which may be linear or branched.

{Examples of (C3) having two acryloyl groups include compounds obtained by reacting two acrylic acids with a polyhydric alcohol. Also, for example, ethylene glycol diacrylate, polyethylene glycol diacrylate (with 2 to 30 ethoxy groups), propylene glycol diacrylate, polypropylene glycol diacrylate (with 2 to 30 propoxy groups), polytetramethylene glycol diacrylate, neopentyl glycol Diacrylate, 3-methyl-1,5-pentanediol diacrylate, 1,6-hexanediol diacrylate, 1,10-decanediol diacrylate, 1,9-nonanediol diacrylate, dimethylol tricyclodecane diacrylate Diacrylate of ethylene oxide adduct of bisphenol A (with 2 to 30 ethoxy groups), diacrylate of propylene oxide adduct of bisphenol A (propoate) Diphenols of bisphenol A ethylene oxide and propylene oxide adducts (sum of ethoxy and propoxy groups is 2 to 40), neopentyl glycol diacrylate hydroxypivalate, 9,9-bis [ 4- (2-acryloyloxyester) phenyl] fluorine, tricyclodecanedimethanol diacrylate and the like.

{Examples of (C3) having three or more acryloyl groups include, for example, compounds obtained by reacting polyhydric alcohol with acrylic acid. Further, for example, trimethylolpropane triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, ethylene oxide-modified pentaerythritol triacrylate, trimethylolpropane triacrylate Glycidyl ether triacrylate, ethylene oxide-modified isocyanuric acid triacrylate, ε-caprolactone-modified tris- (2-acryloxyethyl) isocyanurate, glycerin triacrylate, ethylene oxide-modified glycerin triacrylate, ethylene oxide-modified pentaerythritol tetraacrylate (general formula Indicated by (i) Is, l + m + n + o is less than 4, less than 8 super 24, include compounds) and the like is 48 greater.

Examples of the (D) methacrylate monomer include compounds in which the acryloyl group of the (C) acrylate monomer is replaced with a methacryloyl group.
The photosensitive resin composition of the present invention may contain (D) a methacrylate monomer, and the content is 0 to 5% by mass based on (C) the acrylate monomer. (D) When the content of the methacrylate monomer is more than 5% by mass, the peeled off piece of the cured photosensitive resin layer becomes large at the time of peeling the resist, and the resist is not dissolved.

The content of (C1) in the present invention is 30 to 70% by mass, more preferably 35 to 65% by mass, and further preferably 40 to 60% by mass, based on the total amount of the acrylate monomer (C).
If the content is less than 30% by mass, or if the content is too small, the undercut may increase. If the content is more than 70% by mass, or if the content is too large, alkali In some cases, the photosensitive resin layer easily swells during development, and the adhesion is deteriorated. In addition, fine lines and dots may be peeled off by development.

The photosensitive resin composition of the present invention preferably contains (C2). The content of (C2) is preferably from 30 to 70% by mass, more preferably from 40 to 60% by mass, based on the total amount of the acrylate monomer (C). If the content is less than 30% by mass, the photosensitive resin layer is easily swelled by alkali development, and the adhesion may be deteriorated. If the content is more than 70% by mass, the cured film becomes hard. Since the resist becomes brittle, chipping may occur in the resist due to contact with a transport roller or the like.

In the photosensitive resin composition of the present invention, the content of (A) is preferably 30 to 75% by mass relative to the total amount of (A), (B), (C) and (D), and 35 The content is more preferably from 70 to 70% by mass, and even more preferably from 40 to 60% by mass. When the content of (A) is less than 30% by mass, the film property may be deteriorated or the alkali developability may be reduced. If the content of (A) exceeds 70% by mass, the resolution of the resist pattern may be reduced.

The content of (B) is preferably from 0.1 to 10% by mass, more preferably from 0.2 to 5% by mass, based on the total amount of (A), (B), (C) and (D). Is more preferable. If the content of (B) is less than 0.1% by mass, the photopolymerizability may be insufficient. On the other hand, if it exceeds 10% by mass, the absorption on the surface of the photosensitive resin layer during exposure increases, and the photocrosslinking inside the photosensitive resin layer may be insufficient.

The content of (C) is preferably from 15 to 60% by mass, more preferably from 17 to 55% by mass, based on the total amount of (A), (B), (C) and (D). , 20 to 50% by mass. If the content of (C) is less than 15% by mass, the crosslinkability may decrease, and the photosensitivity may be insufficient. On the other hand, if it exceeds 55% by mass, the tackiness of the film surface may increase.

The photosensitive resin composition of the present invention preferably contains (E) a polymerization inhibitor, and (E) a polymerization inhibitor based on the total amount of (A), (B), (C) and (E). Is more preferably 400 to 1000 ppm.

(E) The polymerization inhibitor has an action of suppressing the photocuring ability of the photosensitive resin composition.
(E) The polymerization inhibitor is not particularly limited as long as it can capture a radical and stop the photochemical reaction of the photosensitive resin composition. Examples thereof include hydroquinone, methylhydroquinone, 4-methoxyphenol, 5-di-tert-butylhydroquinone, tert-butylhydroquinone, 2,6-di-tert-butyl-p-cresol, p-benzoquinone, methyl-p-benzoquinone, tert-butyl-p-benzoquinone, catechol, 4- Hydroquinones such as tert-butylcatechol, 3-methoxycatechol, pyrogallol, picric acid and the like can be mentioned.
Phenoxines such as phenoxazine, 3,7-bis (diethylamino) phenoxazine-5-ium perchlorate, 5-amino-9- (dimethylamino) -10-methylbenzo [a] phenoxazine-7-ium chloride Sazin derivatives are mentioned.
Further, copper chloride, N-nitrosophenylhydroxylamine aluminum salt and the like can be mentioned.

(E) The polymerization inhibitor not only improves the storage stability of the photosensitive resin composition, but also improves the resolution of the resist pattern. These can be used alone or in combination of two or more. Among them, 4-methoxyphenol can be preferably used in view of storage stability, solubility in a solvent, and the like.

The content of (E) is preferably from 400 to 1000 ppm, more preferably from 500 to 900 ppm, based on the total amount of (A), (B), (C) and (E). If the content of (E) is less than 400 ppm, the resolution and the adhesion may decrease. On the other hand, if it exceeds 1000 ppm, the sensitivity may be insufficient.

The photosensitive resin composition of the present invention preferably contains (F) a photochromic agent, and (F) a photochromic agent based on the total amount of (A), (B), (C) and (F). Is more preferably 0.15 to 1.5% by mass.

(F) The photochromic agent is not particularly restricted but includes, for example, leuco crystal violet, leuco victoria blue BH, leuco victoria pure blue BOH, leuco diamond green, leuco acid violet 5B, leuco solar cyanine 6B, leuco brilliant green, And leuco dyes such as 6,6-bisdiethylamino-9-phenylxanthene. Among these, leuco crystal violet is preferably used from the viewpoints of color development, discoloration, and color tone.

The content of (F) is preferably 0.15 to 1.5% by mass, more preferably 0.2 to 1.5% by mass, based on the total amount of (A), (B), (C) and (F). １．０1.0% by mass. When the content of the photochromic agent is less than 0.15% by mass, the contrast between the exposed portion and the unexposed portion may be reduced when the photosensitive resin layer is exposed. On the other hand, when the content of (F) exceeds 1.5% by mass, (F) does not completely dissolve and precipitates as crystals inside the photosensitive resin layer, or the storage stability of the photosensitive resin composition Performance may be reduced.

成分 The photosensitive resin composition of the present invention may contain components other than the above (A) to (F), if necessary. Such components include solvents, plasticizers, colorants (pigments, dyes, pigments), photobleachers, thermal coloration inhibitors, fillers, defoamers, flame retardants, adhesion promoters, leveling agents, and release agents. Accelerators, antioxidants, fragrances, thermosetting agents, water repellents, oil repellents, and the like can be mentioned, and each of (A), (B), (C), (D), (E) and (F) It can be contained in an amount of about 0.01 to 20% by mass based on the total amount. These can be used alone or in combination of two or more.

The photosensitive resin composition of the present invention may be configured as a dry film resist in which a support, a photosensitive resin layer containing the photosensitive resin composition, and a cover film are laminated. Hereinafter, “dry film resist” may be simply abbreviated as “DFR”.
The support only needs to be able to be peeled off from the uncured or cured photosensitive resin layer, and is preferably a transparent film that transmits active light. It is preferable that the thickness of the support is thin because the refraction of light is small, and it is preferable that the thickness of the support is excellent in coating stability, but it is particularly preferable that the thickness be 5 to 50 μm. Examples of such a film include films of polyethylene terephthalate, polycarbonate and the like.

The cover film only needs to be able to be peeled off from the uncured photosensitive resin layer, and a resin having high releasability is used. For example, a polyethylene film; a polypropylene film; a polyalkylene film coated with a release agent such as silicone;
The photosensitive resin layer is a layer comprising the photosensitive resin composition of the present invention.

In the case of a dry film resist, the thickness of the photosensitive resin layer is preferably from 10 to 150 μm, more preferably from 30 to 120 μm. If the thickness of the photosensitive resin layer is too large, problems such as a decrease in resolution and an increase in cost tend to occur. Conversely, if it is too thin, adhesion and acid resistance may decrease.

Next, the plating method of the present invention will be described in detail. The plating method of the present invention can be applied as a plating method when performing plating such as copper plating and nickel plating. Specifically, it is preferably used for applications such as an additive method for forming a metal circuit, a semi-additive method, and an additive method for producing a high-definition metal mask.After forming a resist pattern on a substrate by a photo method, a resist pattern is formed. In this method, a metal pattern or a circuit pattern is formed by plating an exposed base material other than a portion.

For example, in the semi-additive method for producing a printed wiring board, first, a substrate provided with a thin metal layer on an insulating substrate is prepared as a base material. Next, a resist pattern is formed in a portion where a circuit pattern is not formed. Next, electrolytic plating is performed to form a plated metal layer on the exposed surface of the thin metal layer. Subsequently, the resist pattern is removed by a resist peeling step. Thereafter, the thin metal layer is removed by (flash) etching to form a metal pattern / circuit pattern.

Examples of the base material include metal bases such as copper, copper-based alloys (titanium-copper alloy, copper-nickel alloy, etc.); nickel; chromium; iron; tungsten; iron-based alloys such as stainless steel, 42 alloy; Materials can be used.
In addition, copper-clad laminates, electroless-plated substrates, electroplated substrates, electroless-plated catalyst-carrying substrates, flexible copper-clad laminates, flexible stainless steel plates, multi-stage structure substrates, etc., used for manufacturing printed wiring boards, etc. Can be used.

フォト A photo method is used to form a resist pattern on a substrate. In the photo method, first, a coating solution containing a photosensitive resin composition is applied to a base material, and dried to form a photosensitive resin layer containing the photosensitive resin composition. A DFR in which a photosensitive resin layer is formed on a support (carrier film) in advance may be prepared, and the photosensitive resin layer may be transferred to a substrate.

Next, pattern exposure is performed to cure the exposed portion. Next, alkali development is performed to remove the photosensitive resin layer in the non-exposed portions, which are unnecessary portions as the resist pattern, to form a resist pattern including the cured photosensitive resin layer. As the alkali developer used for the alkali development, for example, an aqueous solution of an inorganic basic compound can be used. Examples of the inorganic basic compound include carbonates and hydroxides of lithium, sodium, potassium and the like, and a 0.1 to 3% by mass aqueous solution of sodium carbonate can be preferably used.
A small amount of a surfactant, an antifoaming agent, a solvent, and the like can be appropriately mixed into the developer. Examples of the development processing method include a dip method, a battle method, a spray method, brushing, scraping, and the like, and the spray method is most suitable from the viewpoint of the removal speed. The temperature of the developing treatment is preferably 15 to 35 ° C., and the spray pressure is preferably 0.02 to 0.3 MPa.

In the present invention, the resist pattern after the alkali development may be subjected to a baking treatment. By the baking treatment, an effect of improving the adhesion between the photosensitive resin layer and the substrate, an effect of improving plating resistance, and the like can be obtained. The baking temperature is preferably 80 ° C. or more, and the time is preferably 5 minutes or more. If the substrate is made of copper or the like and is easily discolored by oxidation or the like, baking is performed at about 80 ° C. If the substrate is stainless steel or the like and is hardly oxidized, the temperature of the baking treatment may be 100 ° C. or more, and the treatment may be performed for a long time of 30 minutes or more. Further, before the baking treatment, an actinic ray irradiation treatment such as ultraviolet rays may be performed for the purpose of preventing the photosensitive resin layer from being deformed by heat.

Next, plating is performed on the exposed portion of the substrate on which the resist pattern is not formed to form a metal pattern and a circuit pattern. The plating method is as described above, and may be electrolytic plating or substitution-type or reduction-type electroless plating. The metal (alloy) to be plated (plating metal (alloy)) is not particularly limited.

In the resist stripping step, an aqueous alkaline solution is usefully used as a resist stripping solution. Examples of the basic compound used in the resist stripping solution include inorganic basic salts such as alkali metal silicate, alkali metal hydroxide, alkali metal phosphate, alkali metal carbonate, ammonium phosphate, and ammonium carbonate. Compounds: Examples include organic basic compounds such as ethanolamine, ethylenediamine, propanediamine, triethylenetetramine, morpholine, and tetramethylammonium hydroxide.

In the resist stripping step, it is necessary to adjust the concentration, temperature, spray pressure, ultrasonic conditions, etc. of the resist stripping solution in order to control the solubility of the cured photosensitive resin layer. The higher the temperature of the resist stripping solution, the higher the rate at which the cured photosensitive resin layer dissolves, and a temperature of 40 ° C. or higher is preferred. The concentration of the basic compound in the resist stripping solution is preferably a concentration suitable for solubility. When the basic compound is sodium hydroxide, the concentration is preferably 1 to 4% by mass. As a device, a dip processing device, an ultrasonic device, a shower spray device, or the like can be used.

In the present invention, the photosensitive resin layer which has been cured by pattern exposure and optionally subjected to baking treatment is dissolved in the resist stripping solution when it is removed by the resist stripping solution in the resist stripping step. In the present invention, the `` dissolution '' of the cured photosensitive resin layer means that the photosensitive resin layer is dissolved in the resist stripping solution, or the resist strip is very fine to a size that cannot be visually confirmed. It refers to the state of becoming. The state in which the resist strip is extremely fine includes a state in which the resist strip is dispersed at the molecular assembly level, a state in which the resist strip is dispersed as fine particles of 100 μm or less, and the like.

The present invention is also a method for producing a metal pattern, comprising forming a metal pattern on a substrate using the plating method described above.
For the formation of the metal pattern, it is preferable to use the method described above in each step.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

において In Tables 1 to 3, each component is as follows.

(A-1) Copolymer resin obtained by copolymerizing methyl methacrylate / n-butyl acrylate / methacrylic acid at a mass ratio of 64/15/21 (mass average molecular weight 40,000)

(B-1) 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer (B-2) 4,4′-bis (diethylamino) benzophenone

(C1-1) Ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), wherein l + m + n + o = 35)
(C2-1) Ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), wherein l + m + n + o = 4)

(C3-1) pentaerythritol triacrylate (C3-2) polyethylene glycol @ 600 diacrylate (the number of repeating ethylene oxide is 14)

(D-1) Dimethacrylate of ethylene oxide adduct of bisphenol A (the total number of repeating ethylene oxide is 10)

(E-1) 4-methoxyphenol

(F-1) Leuco crystal violet

Examples 1-1 to 1-6, Comparative Examples 1-1 to 1-4
The components shown in Table 1 were mixed to obtain a photosensitive resin composition and a coating solution. The unit of the amount of each component in Table 1 represents parts by mass.
The obtained coating solution is applied on a polyethylene terephthalate (PET) film (trade name: R310, 16 μm thickness, manufactured by Mitsubishi Chemical Corporation) using an applicator, dried at 80 ° C. for 8 minutes, and the solvent is removed. DFR provided with a photosensitive resin layer (dry film thickness: 30 μm) made of the photosensitive resin composition of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4 on one side of a PET film I got

A stainless steel plate having a surface roughness Ra of 0.01 μm to 1 μm was subjected to surface treatment such as alkali degreasing and acid treatment to obtain photosensitive compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-4. A resin layer was stuck. Next, exposure is performed through a photomask having a pattern of 50 μm line and space, the PET film is peeled off, and alkali development is performed with a 1.0% by mass aqueous solution of sodium carbonate, and the photosensitive resin layer in the non-exposed area is exposed. Was removed to form a resist pattern.

At that time, in the photosensitive resin layer of Comparative Example 1-1 in which the content of (C1) was more than 70% by mass based on the total amount of (C) the acrylate monomer, the resist pattern composed of the cured photosensitive resin layer was After swelling, a 50 μm line & space pattern was detached.
On the other hand, in Examples 1-1 to 1-6, good 50 μm line and space patterns were all produced.

Next, by electroplating using a nickel sulfamate (Ni) bath, a plating film is grown on a portion of the stainless steel plate not covered by the resist pattern, and a Ni metal layer is formed to a thickness of 25 μm. Formed.

At that time, in Comparative Examples 1-2 and 1-3 using the photosensitive resin composition in which the content of (C1) was less than 30% by mass based on the total amount of (C) acrylate monomer, the bottom of the resist pattern line It was found that the plating solution was soaked in the plating solution, and that the image was thin at the bottom of the resist. Therefore, the Ni metal layer entered the bottom of the resist, and a good Ni pattern could not be produced.
On the other hand, in Examples 1-1 to 1-6, good Ni patterns were all produced.

Next, in Examples 1-1 to 1-6 and Comparative Example 1-4, the resist pattern was peeled off by immersion in a 3% by mass aqueous solution of sodium hydroxide (solution temperature: 50 ° C.).
Peeling of the resist pattern by the photosensitive resin compositions of Examples 1-1 to 1-6 was successfully performed.
On the other hand, in Comparative Example 1-4 using a photosensitive resin composition in which the content of (D) was 8.8% by mass and more than 5% by mass based on the total amount of (C) acrylate monomer, 50 μm There is a problem that a residue of the resist pattern remains between the spaces.

In addition, as a result of immersing the peeled pieces of the photosensitive resin layers of Examples 1-1 to 1-6 in a 3% by mass aqueous solution of sodium hydroxide (solution temperature: 50 ° C.) for 3 hours, the peeled pieces could not be visually confirmed. . As a result, when the next work is processed, there is no fear of "tangling" of the resist strip between the Ni patterns.

Examples 2-1 to 2-7, Comparative Example 2-1
The components shown in Table 2 were mixed to obtain a photosensitive resin composition and a coating solution. The unit of the amount of each component in Table 2 represents parts by mass. The content of (E) is the content of (E) with respect to the total amount of (A), (B), (C) and (E), and its unit is ppm by mass.
The obtained coating solution is applied on a polyethylene terephthalate (PET) film (trade name: R310, 16 μm thickness, manufactured by Mitsubishi Chemical Corporation) using an applicator, dried at 80 ° C. for 8 minutes, and the solvent is removed. Then, a DFR having a photosensitive resin layer (dry film thickness: 30 μm) containing the photosensitive resin compositions of Examples 2-1 to 2-7 and Comparative example 2-1 on one surface of a PET film was obtained.

A stainless steel plate having a surface roughness Ra of 0.01 μm to 1 μm is subjected to surface treatment such as alkali degreasing and acid treatment, and the photosensitive resin layers of Examples 2-1 to 2-7 and Comparative example 2-1 are attached. I attached.

Next, exposure was performed through a photomask having a circular dot pattern having a diameter of 200, 150, 100, and 80 μm. Then, the PET film was peeled off, and alkali development was performed with a 1.0% by mass aqueous solution of sodium carbonate. Then, the photosensitive resin layer in the non-exposed area was removed to form a resist pattern.

At this time, in Comparative Example 2-1 which did not contain (C1) as the acrylate monomer (C), more than half of the dot pattern having a diameter of 150 μm or less was lost due to the development step.
In Example 2-7 in which the content of (E) was less than 400 ppm, the dot pattern having a diameter of 100 μm or more remained on the substrate due to the development step, but the dot pattern having a diameter of 80 μm was slightly lost.

On the other hand, in Examples 2-1 to 2-6, even after the development, all the circular dot patterns having diameters of 200, 150, 100, and 80 μm remained on the substrate, showing high adhesion.

At this time, in Comparative Example 2-1, it was found that in the circular dot pattern having a diameter of 200 μm, the plating solution permeated and the resist bottom had a thinned image. Therefore, the Ni metal layer entered under the resist, and a good Ni metal layer could not be formed.
On the other hand, in Examples 2-1 to 2-7, there was no seepage of the plating solution and a good Ni metal layer was formed.

(4) Next, the resist pattern was peeled off by immersion in a 3% by mass aqueous solution of sodium hydroxide (solution temperature: 50 ° C.). The resist patterns using the photosensitive resin compositions of Examples 2-1 to 2-7 and Comparative example 2-1 were successfully peeled off.

Further, the peeled pieces of the photosensitive resin layers of Examples 2-1 to 2-7 and Comparative Example 2-1 were immersed in a 3% by mass aqueous sodium hydroxide solution (liquid temperature of 50 ° C.) for 3 hours. It cannot be confirmed visually. As a result, when the next work is processed, there is no fear of entanglement of the resist strips between the Ni patterns.

Examples 3-1 to 3-7, Comparative examples 3-1 to 3-2
The components shown in Table 3 were mixed to obtain a photosensitive resin composition and a coating solution. The unit of the amount of each component in Table 3 is parts by mass. The obtained coating solution is applied on a polyethylene terephthalate (PET) film (trade name: R310, 16 μm thickness, manufactured by Mitsubishi Chemical Corporation) using an applicator, dried at 80 ° C. for 8 minutes, and the solvent is removed. And a DFR having a photosensitive resin layer (dry film thickness: 50 μm) made of the photosensitive resin composition of Examples 3-1 to 3-7 and Comparative examples 3-1 to 3-2 on one side of a PET film. Obtained.

A stainless steel plate having a surface roughness Ra of 0.01 μm to 1 μm was subjected to a surface treatment such as alkali degreasing and acid treatment to obtain photosensitive compositions of Examples 3-1 to 3-7 and Comparative examples 3-1 to 3-2. A resin layer was stuck.

Next, exposure was performed through a photomask having a circular dot pattern having a diameter of 100, 80, 70, and 60 μm. Subsequently, the PFT film was peeled off, and alkali development was performed using a 1.0% by mass aqueous solution of sodium carbonate. Then, the photosensitive resin layer in the non-exposed area was removed to form a resist pattern.

At this time, the photosensitive resin layer of Example 3-7 in which the content of (F) is less than 0.15% by mass has low sensitivity to exposure, and has the same exposure amount as in Examples 3-1 to 3-6. The curing of the resist did not proceed sufficiently. Therefore, as a result of observing the resist image, more than half of the dot pattern having a diameter of 80 μm or less was lost, but the dot pattern having a diameter of 100 μm remained.

Further, (C) the photosensitive resin layers of Comparative Examples 3-1 and 3-2 containing no (C1) as an acrylate monomer have weak adhesion to the base material, and the dot pattern is reduced by half at all diameters due to the development process. Had been lost.

On the other hand, in Examples 3-1 to 3-6, even after development, the dot pattern remained on the substrate at all diameters, and showed high adhesion.

Next, in Examples 3-1 to 3-7, a plating film was grown on a portion of the stainless steel plate not covered by the resist pattern by electrolytic plating using a nickel sulfamate (Ni) bath. A Ni metal layer was formed so as to have a thickness of 25 μm.

At this time, in Examples 3-1 to 3-7, there was no seepage of the plating solution, and a good Ni metal layer was formed.

(5) Next, the resist pattern was peeled off by immersion in a 3% by mass aqueous solution of sodium hydroxide (solution temperature: 50 ° C.). The resist patterns using the photosensitive resin compositions of Examples 3-1 to 3-7 were successfully peeled off.

In addition, the peeled pieces of the photosensitive resin layers of Examples 3-1 to 3-7 were immersed in a 3% by mass aqueous solution of sodium hydroxide (solution temperature: 50 ° C.) for 3 hours. As a result, the peeled pieces could not be visually confirmed. . As a result, when the next work is processed, there is no concern that the resist strip is entangled between the Ni patterns.

INDUSTRIAL APPLICABILITY The present invention can be widely used in the field of production and use of photosensitive resin compositions. In particular, in the manufacture of printed wiring boards, lead frames, metal masks, shadow masks, semiconductor packages, electrode members, electromagnetic wave shields, etc., the manufacture and use of photosensitive resin compositions for forming resist patterns used in plating. Widely available in the field.

Claims

It contains (A) an alkali-soluble resin, (B) a photopolymerization initiator and (C) an acrylate monomer,
The content of the (D) methacrylate monomer is 0 to 5% by mass with respect to the (C) acrylate monomer,
(C) As an acrylate monomer, (C1) ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i) and having 1 + m + n + o = 24 to 48),
The content of (C1) ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), where l + m + n + o = 24 to 48) is 30 to 70% by mass based on the total amount of (C) acrylate monomer. A photosensitive resin composition comprising:
The photosensitive resin composition contains, as (C) an acrylate monomer, (C2) ethylene oxide-modified pentaerythritol tetraacrylate (a compound represented by the general formula (i), and 1 + m + n + o = 4 to 8); The content of (C2) ethylene oxide-modified pentaerythritol tetraacrylate (compound represented by the general formula (i), where l + m + n + o = 4 to 8) is 30 to 70% by mass based on the total amount of the acrylate monomer. 2. The photosensitive resin composition according to item 1.
The photosensitive resin composition contains (E) a polymerization inhibitor, and based on the total amount of (A) an alkali-soluble resin, (B) a photopolymerization initiator, (C) an acrylate monomer, and (E) a polymerization inhibitor. The photosensitive resin composition according to claim 1, wherein the content of the polymerization inhibitor (E) is 400 to 1000 ppm.
The photosensitive resin composition contains (F) a photochromic agent, and (A) an alkali-soluble resin, (B) a photopolymerization initiator, (C) an acrylate monomer, and (F) a total amount of a photochromic agent. The photosensitive resin composition according to claim 1, wherein the content of the photocoloring agent (F) is 0.15 to 1.5% by mass.
Forming a photosensitive resin layer containing the photosensitive resin composition according to any one of claims 1 to 4 on a substrate, and then performing pattern exposure to cure the exposed portions, Plating characterized by removing the photosensitive resin layer in the non-exposed areas by performing alkali development, forming a resist pattern including the cured photosensitive resin layer, and then plating the exposed base material Method.
A method for producing a metal pattern, comprising: forming a metal pattern on a substrate using the plating method according to claim 5.