JP2010026431A - Negative radiation-sensitive resin composition - Google Patents

Abstract

【選択図】なしProvided is a negative radiation-sensitive resin composition suitable for forming a fine bump forming material that can be easily and sufficiently peeled off from a substrate after plating.
(A) (a1) a structural unit derived from a radically polymerizable compound having a phenolic hydroxyl group, (a2) a structural unit derived from a radically polymerizable compound having a carboxyl group, and (a3) another radical polymerization. An alkali-soluble copolymer having a constitutional unit derived from a functional compound, (B) a crosslinking agent containing a crosslinking agent represented by the following formula (1), and (C) a radiation-sensitive radical polymerization initiator. A negative-type radiation-sensitive resin composition.

[Selection figure] None

Description

  The present invention relates to a negative radiation sensitive resin composition. More specifically, the present invention relates to a negative radiation-sensitive resin composition suitable for photo applications such as bump formation performed when a semiconductor or electronic component is mounted on a circuit board.

  Photo application is the application of a radiation-sensitive resin composition to the surface of a workpiece to form a coating film, which is then patterned by photolithography and is used as a mask for chemical etching, electrolytic etching, or electroplating. Is a general term for technologies for manufacturing various precision parts singly or in combination, and has become the mainstream of current precision micromachining technology (see, for example, Patent Document 1).

  In recent years, with the downsizing of electronic devices, LSIs are rapidly becoming highly integrated and multi-layered. For this reason, a multi-pin mounting method on a substrate for mounting an LSI on an electronic device is required. For example, bare chip mounting by a tape automated bonding (TAB) method or a flip chip method has been attracting attention. In such a multi-pin mounting method, it is necessary to dispose a protruding electrode having a height of 15 μm or more, called a bump, which is a connection terminal, on the substrate with high accuracy, and in order to cope with LSI miniaturization in the future. Therefore, it is expected that higher accuracy of bumps will be required.

  The resist pattern used when forming the bump is sometimes called a bump forming material (see, for example, Patent Document 2). The requirements for the radiation-sensitive resin composition include that a resist pattern having a thickness of 20 μm or more can be formed, that the pattern has adhesion to the substrate, and that the pattern is plated when plating is performed for bump formation. Examples thereof include good wettability and plating solution resistance to the solution, and that the pattern can be easily and sufficiently peeled off from the substrate after the plating is performed.

However, in recent years, with the miniaturization of resist patterns, resist patterns formed using conventional radiation-sensitive resin compositions are difficult to peel off from the substrate with a stripping solution after plating. The problem of being is becoming more prominent.
Japanese Patent Laid-Open No. 2002-14466 JP 2000-39709 A

  The present invention is a negative-type radiation-sensitive resin that can be easily and sufficiently peeled off from a substrate with a stripping solution after plating and is suitable for forming a fine bump-forming material with excellent resolution. An object is to provide a composition.

  The present inventors have intensively studied to solve the above problems. As a result, the inventors have found that the above-mentioned problems can be solved by using a negative radiation-sensitive resin composition containing an alkali-soluble copolymer having a specific structural unit and a specific cross-linking agent, and to complete the present invention. It came.

That is, the present invention relates to the following [1] to [4].
[1] (A) (a1) a structural unit derived from a radical polymerizable compound having a phenolic hydroxyl group, (a2) a structural unit derived from a radical polymerizable compound having a carboxyl group, and (a3) other radical polymerizable An alkali-soluble copolymer having a structural unit derived from a compound, (B) a crosslinking agent containing a crosslinking agent represented by the following formula (1), and (C) a radiation-sensitive radical polymerization initiator Negative-type radiation-sensitive resin composition.

［式（１）中、Ｘは下記式（２）または（３）で示される有機基であり、６つあるＸは同一でも異なっていてもよい。

[In the formula (1), X is an organic group represented by the following formula (2) or (3), and the six Xs may be the same or different.

式（２）中、ｎは２〜４の整数、ｍは０〜１０の整数であり、式（３）中、ｌは０〜２の整数である。式（２）および（３）中、Ｒは水素原子または（メタ）アクリロイル基を表す。ただし、式（１）で示される架橋剤は、少なくとも４個の（メタ）アクリロイル基を有する。］
［２］前記フェノール性水酸基を有するラジカル重合性化合物が、α−メチル−ｐ−ヒドロキシスチレンであることを特徴とする前記［１］に記載のネガ型感放射線性樹脂組成物。

In formula (2), n is an integer of 2 to 4, m is an integer of 0 to 10, and in formula (3), l is an integer of 0 to 2. In formulas (2) and (3), R represents a hydrogen atom or a (meth) acryloyl group. However, the crosslinking agent represented by the formula (1) has at least four (meth) acryloyl groups. ]
[2] The negative radiation-sensitive resin composition according to [1], wherein the radical polymerizable compound having a phenolic hydroxyl group is α-methyl-p-hydroxystyrene.

[3] The negative radiation-sensitive resin composition according to [1] or [2], wherein the crosslinking agent represented by the formula (1) is dipentaerythritol hexaacrylate.
[4] When the total constituent unit of the alkali-soluble copolymer (A) is 100% by weight, the content of the constituent unit derived from the radical polymerizable compound having the (a1) phenolic hydroxyl group is 1 to 50% by weight. %, The content of the structural unit derived from the radically polymerizable compound having (a2) carboxyl group is 1 to 50% by weight, and the content of the structural unit derived from the other (a3) other radically polymerizable compound The negative radiation-sensitive resin composition according to any one of [1] to [3], wherein the amount is 5 to 80% by weight.

  By using the negative radiation sensitive resin composition of the present invention, after plating, it can be easily and sufficiently peeled off from the substrate with a stripping solution or the like, and for fine bump formation with excellent resolution. A material can be formed. That is, the bump forming material formed from the resin composition is excellent in resolution and releasability after plating.

Hereinafter, the negative radiation sensitive resin composition of the present invention will be described in detail. In the following, a resist pattern may be exemplified as a bump forming material formed from the resin composition.

[Negative type radiation sensitive resin composition]
The negative radiation-sensitive resin composition of the present invention comprises (A) an alkali-soluble copolymer having a specific structural unit, (B) a cross-linking agent containing a specific cross-linking agent, and (C) a radiation-sensitive radical polymerization. It contains an initiator. The resin composition may contain (D) a solvent. Hereinafter, the respective components are also referred to as “alkali-soluble copolymer (A)”, “crosslinking agent (B)”, “radiation sensitive radical polymerization initiator (C)” and “solvent (D)”, respectively.

<Alkali-soluble copolymer (A)>
The alkali-soluble copolymer (A) used in the present invention comprises (a1) a structural unit derived from a radical polymerizable compound having a phenolic hydroxyl group (hereinafter also referred to as “structural unit (a1)”), (a2) carboxyl A structural unit derived from a radical polymerizable compound having a group (hereinafter also referred to as “structural unit (a2)”), and (a3) a structural unit derived from another radical polymerizable compound (hereinafter referred to as “structural unit (a3)”). Is also called an alkali-soluble copolymer. In the present invention, “alkali-soluble” refers to a property of being dissolved in an alkaline developer to such an extent that the desired development processing can be performed.

  In the alkali-soluble copolymer (A), the content of the structural unit (a1) is preferably 1 to 50% by weight, more preferably 5 to 40% by weight, particularly preferably 100% by weight. Is 10 to 40% by weight, and the content of the structural unit (a2) is preferably 1 to 50% by weight, more preferably 5 to 40% by weight, and particularly preferably 5 to 30% by weight. ) Is preferably 5 to 80% by weight, more preferably 10 to 70% by weight, and particularly preferably 20 to 60% by weight. The total content of the structural units (a1) to (a3) is preferably 100% by weight.

  When the content of the structural unit (a1) is less than the above range, the resolution of the resist pattern may be lowered. Further, when the content of the structural unit (a1) exceeds the above range, that is, when a radically polymerizable compound having a phenolic hydroxyl group is used in a large amount, the molecular weight of the alkali-soluble copolymer (A) cannot be sufficiently increased. , It may be difficult to form a coating film having a thickness of 20 μm or more.

  If the content of the structural unit (a2) is less than the above range, the solubility of the alkali-soluble copolymer (A) in the alkaline developer is lowered, resulting in a film residue after development, and the resolution of the resist pattern is lowered. There is. Further, when the content of the structural unit (a2) exceeds the above range, the solubility of the alkali-soluble copolymer (A) in the alkali developer becomes too large, and the exposed area is dissolved, that is, the film reduction is large. May be.

  When the content of the structural unit (a3) is in the above range, the mechanical properties of the alkali-soluble copolymer (A) are good, so that the mechanical properties of the resist pattern can be improved.

  The weight average molecular weight (Mw) of the alkali-soluble copolymer (A) is usually 1000 to 100000, preferably 2000 to 50000, more preferably 3000 to 30000 in terms of polystyrene by gel permeation chromatography.

The alkali-soluble copolymer (A) includes, for example, a radical polymerizable compound (a1 ′) having a phenolic hydroxyl group, a radical polymerizable compound (a2 ′) having a carboxyl group, and another radical polymerizable compound (a3 ′). Can be obtained by radical copolymerization in a polymerization solvent in the presence of a polymerization catalyst in such an amount that the content of structural units derived from these radical polymerizable compounds is in the above range.

<< Radically polymerizable compound having phenolic hydroxyl group (a1 ') >>
Examples of the radical polymerizable compound (a1 ′) having a phenolic hydroxyl group include o-
Hydroxystyrene, m-hydroxystyrene, p-hydroxystyrene, α-methyl-o-hydroxystyrene, α-methyl-m-hydroxystyrene, α-methyl-p-hydroxystyrene, 2-allylphenol, 4-allylphenol, Examples include 2-allyl-6-methylphenol, 2-allyl-6-methoxyphenol, 4-allyl-2-methoxyphenol, 4-allyl-2,6-dimethoxyphenol, and 4-allyloxy-2-hydroxybenzophenone.

  These may be used alone or in combination of two or more. Of these, p-hydroxystyrene and α-methyl-p-hydroxystyrene are preferable, and α-methyl-p-hydroxystyrene is particularly preferable.

Moreover, it replaces with the said radically polymerizable compound (a1 ') or the radically polymerizable compound which has the phenolic hydroxyl group protected by the functional group which can be converted into a phenolic hydroxyl group with the said radically polymerizable compound (a1') (A1 ′) A precursor can also be used.

Examples of the radical polymerizable compound (a1 ′) precursor include p-acetoxystyrene, α-methyl-p-acetoxystyrene, p-benzyloxystyrene, p-tert-butoxystyrene, and p-tert-butoxycarboni. Examples include loxystyrene and p-tert-butyldimethylsiloxystyrene.

The structural unit derived from the precursor of the radical polymerizable compound (a1 ′) can be easily converted to a phenolic hydroxyl group by synthesizing a copolymer and then appropriately treating it, for example, by hydrolysis using hydrochloric acid or the like. It can convert into the structural unit derived from the radically polymerizable compound (a1 ') which has.

<< Radical polymerizable compound having a carboxyl group (a2 ') >>
The radically polymerizable compound (a2 ′) having a carboxyl group is used for adjusting the alkali solubility of the alkali-soluble copolymer (A).

  Examples of the radical polymerizable compound (a2 ′) include acrylic acid, methacrylic acid, crotonic acid, 2-succinoylethyl (meth) acrylate, 2-malenoylethyl (meth) acrylate, and 2-hexahydrophthaloyl. Ethyl (meth) acrylate, ω-carboxy-polycaprolactone monoacrylate (commercially available products such as Aronix M-5300 manufactured by Toagosei Co., Ltd.), phthalic acid monohydroxyethyl acrylate (commercially available products such as Aronix M manufactured by the same company) -5400), monocarboxylic acids such as acrylic acid dimer (commercially available product, Aronix M-5600, for example); and dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, mesaconic acid and itaconic acid.

  These may be used alone or in combination of two or more. Of these, acrylic acid, methacrylic acid, and 2-hexahydrophthaloylethyl methacrylate (commercially available products such as acrylate ester HH manufactured by Mitsubishi Rayon Co., Ltd.) are preferable.

<< Other radical polymerizable compound (a3 ') >>
The other radically polymerizable compound (a3 ′) is mainly used for moderately controlling the mechanical properties of the alkali-soluble copolymer (A). Here, “other” means a radical polymerizable compound other than the above-mentioned radical polymerizable compounds (a1 ′) and (a2 ′).

  Examples of the other radical polymerizable compound (a3 ′) include (meth) acrylic acid alkyl esters, (meth) acrylic acid aryl esters, dicarboxylic acid diesters, aromatic vinyls, nitrile group-containing polymerizable compounds, Examples include amide bond-containing polymerizable compounds, fatty acid vinyls, chlorine-containing polymerizable compounds, and conjugated diolefins.

Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, sec-butyl (meth) acrylate, tert-butyl (meth) acrylate, n-hexyl (Meth) acrylate, cyclohexyl (meth) acrylate, 2-methylcyclohexyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, methoxydipropylene glycol (Meth) acrylate, butoxy-dipropylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxypropylene glycol (meth) acrylate, etc. Alkyl esters of acrylic acid;
(Meth) acrylic acid aryl esters such as phenyl (meth) acrylate and benzyl (meth) acrylate; dicarboxylic acid diesters such as diethyl maleate, diethyl fumarate and diethyl itaconate; styrene, o-methylstyrene, m-methyl Aromatic vinyls such as styrene, p-methylstyrene and p-methoxystyrene;
Nitrile group-containing polymerizable compounds such as acrylonitrile and methacrylonitrile; Amide bond-containing polymerizable compounds such as acrylamide and methacrylamide; Fatty acid vinyls such as vinyl acetate; Chlorine-containing polymerizable compounds such as vinyl chloride and vinylidene chloride; Examples thereof include conjugated diolefins such as 3-butadiene, isoprene, and 1,4-dimethylbutadiene.
These may be used alone or in combination of two or more. Of these, (meth) acrylic acid alkyl esters and aromatic vinyls are preferred.

≪Polymerization solvent≫
Examples of the polymerization solvent used in producing the alkali-soluble copolymer (A) include alcohols such as methanol, ethanol, ethylene glycol, diethylene glycol, and propylene glycol; cyclic ethers such as tetrahydrofuran and dioxane;
Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl Alkyl ethers of polyhydric alcohols such as ethers;
Alkyl ether acetates of polyhydric alcohols such as ethylene glycol ethyl ether acetate, diethylene glycol ethyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, dipropylene glycol methyl ether acetate; aromatic hydrocarbons such as toluene and xylene Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, diacetone alcohol;
Ethyl acetate, butyl acetate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, 3 -Esters such as ethyl methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, ethyl acetate and butyl acetate.
Of these, cyclic ethers, polyhydric alcohol alkyl ethers, polyhydric alcohol alkyl ether acetates, ketones, and esters are preferred.

≪Polymerization catalyst≫
As the polymerization catalyst used when producing the alkali-soluble copolymer (A), a normal radical polymerization initiator can be used. Examples of the radical polymerization initiator include 2,2′-
Azo compounds such as azobisisobutyronitrile, 2,2′-azobis- (2,4-dimethylvaleronitrile), 2,2′-azobis- (4-methoxy-2-dimethylvaleronitrile); benzoyl peroxide, Organic peroxides such as lauroyl peroxide, tert-butylperoxypivalate, 1,1′-bis- (tert-butylperoxy) cyclohexane; and hydrogen peroxide.

  When an organic peroxide is used as the radical polymerization initiator, a redox initiator may be combined with an inorganic reducing agent such as iron (II) hydroxide or sodium sulfite; an organic reducing agent such as alcohol or polyamine.

<Crosslinking agents (B)>
The crosslinking agents (B) used in the present invention include a crosslinking agent represented by the following formula (1) (hereinafter also referred to as “crosslinking agent (1)”). In addition, a crosslinking agent other than the crosslinking agent (1) (hereinafter also referred to as “crosslinking agent (2)”) may be used together with the crosslinking agent (1) as long as the object of the present invention is not impaired.

式（１）中、Ｘは下記式（２）または（３）で示される有機基であり、６つあるＸは同一でも異なっていてもよい。

In formula (1), X is an organic group represented by the following formula (2) or (3), and the six Xs may be the same or different.

式（２）中、ｎは２〜４、好ましくは２〜３の整数であり、ｍは０〜１０、好ましくは０〜５の整数であり、式（３）中、ｌは０〜２、好ましくは０〜１の整数である。式（２）および（３）中、Ｒは水素原子または（メタ）アクリロイル基を表す。ただし、式（１）で示される架橋剤は、少なくとも４個、好ましくは５〜６個の（メタ）アクリロイル基を有する。

In formula (2), n is an integer of 2 to 4, preferably 2 to 3, m is an integer of 0 to 10, preferably 0 to 5, and in formula (3), l is 0 to 2, Preferably it is an integer of 0-1. In formulas (2) and (3), R represents a hydrogen atom or a (meth) acryloyl group. However, the crosslinking agent represented by the formula (1) has at least 4, preferably 5 to 6 (meth) acryloyl groups.

Examples of the crosslinking agent represented by the above formula (1) include dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more. Among these, dipentaerythritol hexaacrylate is preferable in that a resist pattern excellent in sensitivity and peelability can be obtained.

Examples of the cross-linking agent (2) include polyfunctional (meth) acrylate compounds (excluding the cross-linking agent (1); the same shall apply hereinafter).
Examples of the polyfunctional (meth) acrylate compound include ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, Butylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (Meth) acrylate, tetramethylolpropane tetra (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, tris (2-hydroxyethyl) iso Anurate tri (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, epoxy (meth) acrylate obtained by adding (meth) acrylic acid to diglycidyl ether of bisphenol A, bisphenol A di (meth) acrylate, bisphenol A di (Meth) acryloyloxyethyl ether, bisphenol A di (meth) acryloyloxyethyloxyethyl ether, bisphenol A di (meth) acryloyloxymethyloxyethyl ether, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, An example is pentaerythritol poly (meth) acrylate.

  Moreover, the said polyfunctional (meth) acrylate compound can also use the compound marketed as it is. Specific examples of commercially available compounds include Aronix M-210, M-240, M-245, M-309, M-310, M-6100, M-6200, and M-6250. M-6300, M-6400, M-6500, M-7500, M-7100, M-8030, M-8060, M-8100, M-9050 (above, manufactured by Toagosei Co., Ltd.) KAYARADR-551, R-712, TMPTA, HDDA, TPGDA, PEG400DA, MANDA, HX-220, HX-620, R-604 (Nippon Kayaku Co., Ltd.) Biscort # 260, 295, 300, 312, 335HP, 360, GPT, 3PA, 400 (above, manufactured by Osaka Organic Chemical Co., Ltd.).

  The content of the crosslinking agent (B) in the negative radiation-sensitive resin composition of the present invention is preferably 10 to 250 parts by weight, more preferably 100 parts by weight with respect to 100 parts by weight of the alkali-soluble copolymer (A). 20 to 200 parts by weight, particularly preferably 25 to 150 parts by weight. When the content of the cross-linking agent (B) is less than the above range, the sensitivity at the time of exposure tends to decrease, and when it exceeds the above range, the compatibility with the alkali-soluble copolymer (A) is deteriorated and the storage stability is decreased. Or forming a coating film of 20 μm or more may be difficult.

  Moreover, the usage-amount of the crosslinking agent (1) in this invention becomes like this. Preferably it is 30 weight% or more with respect to 100 weight% of crosslinking agents (B), More preferably, it is 30-100 weight%, Most preferably, it is 40-85. % By weight. By using the crosslinking agent (1) in an amount within the above range, the peelability of the resist pattern can be improved.

<Radiation sensitive radical polymerization initiator (C)>
Examples of the radiation-sensitive radical polymerization initiator (C) used in the present invention include α-diketones such as benzyl and diacetyl; acyloines such as benzoin; acylo such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether. Inethers; thioxanthone, 2,4-diethylthioxanthone, thioxanthone-4
-Benzophenones such as sulfonic acid, benzophenone, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone;
Acetophenone, p-dimethylaminoacetophenone, α, α-dimethoxy-α-acetoxybenzophenone, α, α-dimethoxy-α-phenylacetophenone, p-methoxyacetophenone, 1- [2-methyl-4-methylthiophenyl] -2- Acetophenones such as morpholinopropan-1-one, α, α-dimethoxy-α-morpholino-methylthiophenylacetophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one ;
Quinones such as anthraquinone and 1,4-naphthoquinone; halogen compounds such as phenacyl chloride, tribromomethylphenyl sulfone and tris (trichloromethyl) -s-triazine; [1,2'-bisimidazole] -3,3 ' , 4,4′-tetraphenyl,
[1,2'-bisimidazole] -1,2'-dichlorophenyl-3,3 ', 4,4'-tetraphenyl, 2,2'-bis (2-chlorophenyl) -4,5,4', 5 Bisimidazoles such as'-tetraphenyl-1,2'-biimidazole, peroxides such as di-tert-butyl peroxide; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide Is mentioned.

  Examples of commercially available products include Irgacure 184, 500, 651, 107, CGI369, G24-61 (above, manufactured by Ciba Specialty Chemicals Co., Ltd.), Lucillin LR8728, TPO (above, BASF Corp.). ), Darocur 1116, 1173 (above, manufactured by Ciba Specialty Chemicals Co., Ltd.), Ubekrill P36 (manufactured by UCB Co., Ltd.).

  In this invention, a radiation sensitive radical polymerization initiator (C) may be used individually by 1 type, and may use 2 or more types together. In addition to the radiation-sensitive radical polymerization initiator (C), a hydrogen-donating compound such as mercaptobenzothiazole or mercaptobenzoxazole or a sensitizer may be used as necessary.

Among these, 1- [2-methyl-4-methylthiophenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane-1 -One, acetophenones such as α, α-dimethoxy-α-phenylacetophenone; phenacyl chloride, tribromomethylphenyl sulfone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1,2'-bisimidazoles A combination of 4,4′-bis (diethylamino) benzophenone and mercaptobenzothiazole, Lucillin TPO, Irgacure 651 and the like are preferable.

  The content of the radiation-sensitive radical polymerization initiator (C) in the negative radiation-sensitive resin composition of the present invention is preferably 0.1 to 50 with respect to 100 parts by weight of the alkali-soluble copolymer (A). Parts by weight, more preferably 1 to 30 parts by weight, particularly preferably 2 to 30 parts by weight. When content of the said polymerization initiator (C) is less than the said range, it will be easy to receive the influence (sensitivity fall) of the radical deactivation by oxygen. Moreover, when content of the said polymerization initiator (C) exceeds the said range, there exists a tendency for compatibility with the said polymerization initiator (C) and another component to worsen, or for storage stability to fall.

<Solvent (D)>
In the present invention, it is preferable to use a solvent (D) that can uniformly dissolve other components and does not react with other components. Examples of such a solvent include a polymerization solvent used in producing the alkali-soluble copolymer (A), and N-methylformamide, N, N-dimethylformamide, N-methylformanilide, N-methylacetamide, N, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, benzyl ethyl ether, dihexyl ether, acetonyl acetone, isophorone, caproic acid, caprylic acid, 1-octanol, 1-nonanol, benzyl alcohol, Examples include high-boiling solvents such as benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, and phenyl cellosolve acetate.

  These may be used alone or in combination of two or more. Of these, alkyl ethers of polyhydric alcohols such as ethylene glycol monoethyl ether and diethylene glycol monomethyl ether; solubility, non-reactivity with other components, and ease of film formation; ethylene glycol ethyl ether Alkyl ether acetates of polyhydric alcohols such as acetate and propylene glycol methyl ether acetate; ketones such as diacetone alcohol; esters such as ethyl 2-hydroxypropionate, ethyl 3-ethoxypropionate, and methyl 3-methoxypropionate Is preferred.

  Content of the solvent (D) in the negative radiation sensitive resin composition of this invention can be suitably determined according to the use of this composition, a coating method, etc. For example, when a resist pattern having a thickness of 20 μm or more is formed in order to produce a plated model such as a bump, the solid content concentration of the negative radiation-sensitive resin composition is 40% by weight or more. What is necessary is just to adjust content of a solvent (D).

<Additives>
The negative radiation-sensitive resin composition of the present invention includes the above-mentioned alkali-soluble copolymer (A), crosslinking agents (B), radiation-sensitive radical polymerization initiator (C), and preferably used solvent (D). In addition, various additives may be further blended as necessary.

≪Thermal polymerization inhibitor≫
A thermal polymerization inhibitor can be blended in the negative radiation sensitive resin composition of the present invention. Examples of the thermal polymerization inhibitor include pyrogallol, benzoquinone, hydroquinone, methylene blue, tert-butylcatechol, monobenzyl ether, methylhydroquinone, amylquinone, amyloxyhydroquinone, n-butylphenol, phenol, hydroquinone monopropyl ether. 4,4 ′-(1-methylethylidene) bis (2-methylphenol), 4,4 ′-(1-methylethylidene) bis (2,6-dimethylphenol),
4,4- [1- [4- (1- (4-hydroxyphenyl) -1-methylethyl) phenyl] ethylidene] bisphenol, 4,4 ′, 4 ″ -ethylidene tris (2-methylphenol), 4, 4 ', 4 "-ethylidenetrisphenol, 1,1,3-tris (2,5-
And dimethyl-4-hydroxyphenyl) -3-phenylpropane. The blending amount of the thermal polymerization inhibitor is preferably 5 parts by weight or less with respect to 100 parts by weight of the alkali-soluble copolymer (A).

≪Surfactant≫
In the negative radiation sensitive resin composition of the present invention, a surfactant can also be blended for the purpose of improving coating properties, antifoaming properties, leveling properties and the like. Examples of the surfactant include BM-1000, BM-1100 (manufactured by BM Chemie), MegaFuck F142D, F172, F173, and F183 (manufactured by Dainippon Ink & Chemicals, Inc.). , FLORARD FC-135, FC-170C, FC-430, FC-431 (above, manufactured by Sumitomo 3M Limited), Surflon S-112, S-113, S-131, S-141 S-145 (above, manufactured by Asahi Glass Co., Ltd.), SH-28PA, i-190, i-193, SZ-6032, SF-8428 (above, manufactured by Toray Dow Corning Silicone Co., Ltd.), and Ftergent FTX -218 (manufactured by Neos Co., Ltd.) and other commercially available fluorine-based surfactants. The compounding amount of the surfactant is an alkali-soluble copolymer (
A) The amount is preferably 5 parts by weight or less with respect to 100 parts by weight.

≪Adhesion aid≫
In the negative radiation sensitive resin composition of the present invention, an adhesion assistant may be blended in order to improve the adhesion between the coating film formed from the composition and the substrate. A functional silane coupling agent is effective as the adhesion aid. Here, the functional silane coupling agent means a silane coupling agent having a reactive substituent such as a carboxyl group, a methacryloyl group, an isocyanate group, and an epoxy group. For example, trimethoxysilylbenzoic acid, γ-methacrylic acid is used. Roxypropyltrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Can be mentioned. The amount of the adhesion aid is preferably 20 parts by weight or less with respect to 100 parts by weight of the alkali-soluble copolymer (A).

≪Carboxylic acid and its anhydride, filler, colorant, viscosity modifier≫
In the negative radiation sensitive resin composition of the present invention, acetic acid, propionic acid, n-butyric acid, iso-butyric acid, n-valeric acid, iso-valeric acid are used for fine adjustment of solubility in an alkali developer. Monocarboxylic acids such as benzoic acid and cinnamic acid; lactic acid, 2-hydroxybutyric acid, 3-hydroxybutyric acid, salicylic acid, m-hydroxybenzoic acid, p-hydroxybenzoic acid, 2-hydroxycinnamic acid, 3-hydroxycinnamic acid Hydroxy monocarboxylic acids such as cinnamic acid, 4-hydroxycinnamic acid, syringic acid;
Oxalic acid, succinic acid, glutaric acid, adipic acid, maleic acid, itaconic acid, hexahydrophthalic acid, phthalic acid, isophthalic acid, 5-hydroxyisophthalic acid, terephthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,2, Polyvalent carboxylic acids such as 4-cyclohexanetricarboxylic acid, trimellitic acid, pyromellitic acid, cyclopentanetetracarboxylic acid, butanetetracarboxylic acid, 1,2,5,8-naphthalenetetracarboxylic acid;
Itaconic anhydride, succinic anhydride, citraconic anhydride, dodecenyl succinic anhydride, tricarbanilic anhydride, maleic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hymic anhydride, 1,2,3,4-butanetetra Carboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, phthalic anhydride, pyromellitic anhydride, trimellitic anhydride, benzophenone tetracarboxylic dianhydride, ethylene glycol bis (trimellitic anhydride), glycerin tris (trimellitic anhydride) An acid anhydride such as) can also be blended.

  A filler, a colorant, and a viscosity modifier can also be mix | blended with the negative radiation sensitive resin composition of this invention. Examples of the filler include silica, alumina, talc, bentonite, zirconium silicate, and powdered glass. Examples of the colorant include extender pigments such as alumina white, clay, barium carbonate, and barium sulfate; , Lead white, yellow lead, red lead, ultramarine, bitumen, titanium oxide, zinc chromate, bengara, carbon black and other inorganic pigments; brilliant carmine 6B, permanent red 6B, permanent red R, benzidine yellow, phthalocyanine blue, phthalocyanine green Organic pigments such as magenta, rhodamine, and the like; direct dyes such as direct scarlet and direct orange; and acid dyes such as roserine and methanyl yellow. Examples of the viscosity modifier include bentonite and silica gel. , Aluminum powder.

  The various additives described above can be blended within a range that does not impair the essential characteristics of the present invention, and the total blending amount is preferably 50% by weight or less based on the entire negative-type radiation-sensitive resin composition. It is.

<Preparation of negative radiation sensitive resin composition>
The negative radiation-sensitive resin composition of the present invention can be prepared by mixing and stirring the above-mentioned components by a usual method when no filler and pigment are added. Moreover, when adding a filler and a pigment to the resin composition, these components and each of the other components described above may be dispersed and mixed using a disperser such as a dissolver, a homogenizer, or a three roll mill. Good. Moreover, you may filter said each component or the said resin composition using a mesh, a membrane filter, etc. further as needed.

[Application of negative radiation sensitive resin composition]
The negative radiation-sensitive resin composition of the present invention can be used by any of a method used as a liquid resin composition and a method used as a radiation-sensitive dry film described below, depending on applications.

<Radiation sensitive dry film>
The radiation-sensitive dry film is formed, for example, on a base film, a photosensitive layer made of the negative radiation-sensitive resin composition of the present invention formed on the base film, and on the photosensitive layer as necessary. Cover film. Further, a layer made of a water-soluble resin composition may be formed between the photosensitive layer and the base film.

  Examples of the base film include synthetic resin films such as polyethylene terephthalate (PET), polyethylene, polypropylene, polycarbonate, polyether sulfone, and polyvinyl chloride, and the film preferably has flexibility. The thickness of the base film is preferably in the range of 15 to 125 μm.

  The photosensitive layer is made of the negative radiation sensitive resin composition of the present invention, and is formed by applying and drying the resin composition on the base film. In order to apply the resin composition on the base film, for example, an applicator, a bar coater, a roll coater, a curtain flow coater, a die coater, a spin coater, or screen printing is used. The thickness of the photosensitive layer is preferably in the range of 10 to 150 μm after drying.

  The cover film is for stably protecting the photosensitive layer when storing the radiation-sensitive dry film, and is removed when the dry film is used. Therefore, the cover film needs to have appropriate peelability so that it does not peel off during storage and can be easily peeled off during use. Moreover, it is preferable that a cover film has oxygen impermeability and can prevent the bad influence of oxygen at the time of exposure.

  Examples of the cover film that satisfies the above conditions include a PET film, a polypropylene film, a polyethylene film, and a film in which silicone is coated or baked on the surface of these films. The thickness of the cover film is preferably in the range of 15 to 100 μm.

  Moreover, you may form the layer which consists of the said water-soluble resin composition in order to prevent adhesion with the photomask for pattern formation used at the time of exposure, and the said photosensitive layer. The layer made of the water-soluble resin composition is formed by applying and drying a 5 to 20% by weight aqueous solution of polyvinyl alcohol or partially saponified polyvinyl acetate on the base film. The thickness of the layer made of the water-soluble resin composition is preferably in the range of 1 to 10 μm after drying.

  Examples of the water-soluble resin composition include polyvinyl alcohol, polyvinyl pyrrolidone, ethylene-vinyl alcohol copolymer, and ethylene-vinyl acetate copolymer.

  In addition, ethylene glycol, propylene glycol, polyethylene glycol, etc. can also be added to the said water-soluble resin composition. In preparing the water-soluble resin composition, considering the viscosity and antifoaming property of the resin composition, a solvent (for example, methanol, ethylene glycol monomethyl ether, acetone, etc.) or a commercially available water-soluble antifoaming agent is used. An agent or the like can also be added.

[Method of forming plated model]
By using the negative radiation-sensitive resin composition of the present invention, after plating, it is possible to easily and sufficiently peel from the substrate with a stripping solution or the like (for example, a fine plated shaped article forming material (for example, Bump forming material) can be formed. Below, the formation method of a resist pattern as a plating modeling object formation material and the formation method of plating modeling objects, such as a bump and wiring using this pattern, are demonstrated in detail.

1. Method for forming photosensitive layer
1-1. When using a liquid resin composition, the negative radiation-sensitive resin composition of the present invention is applied onto a predetermined substrate to form a coating film, and the desired photosensitive layer can be formed by removing the solvent by heating. it can.

  In the present invention, when a plated model is formed on a substrate by plating, the surface of the substrate needs to be coated with a metal. The method for coating the surface of the substrate with a metal is not particularly limited, and examples thereof include a method for depositing a metal and a method for sputtering.

  Examples of the method for applying the resin composition on the substrate include a spin coating method, a roll coating method, a screen printing method, and an applicator method. Moreover, although the drying conditions of a coating film change with kinds of each component in the said resin composition, a mixture ratio, the thickness of a coating film, etc., drying temperature is 60-160 degreeC normally, Preferably it is 80-150 degreeC. The drying time is about 5 to 20 minutes. If the drying time is too short, the contact state between the substrate and the photosensitive layer at the time of development will be poor, and if it is too long, the resolution may be lowered due to heat fogging.

1-2. When using a radiation sensitive dry film When using the said radiation sensitive dry film, a cover film is peeled and a photosensitive layer is transcribe | transferred on a board | substrate. As the transfer method, a thermocompression bonding method in which the substrate is heated in advance is preferable. In the case where a plated model is formed on a substrate by plating, a substrate with a metal coated on the surface is used in the same manner as in the case of using a liquid resin composition when using a radiation-sensitive dry film.

2. Radiation exposure method The photosensitive layer formed on the substrate is exposed to ultraviolet rays or visible rays having a wavelength of 300 to 500 nm through a photomask having a predetermined pattern to form a latent image of the pattern.

Examples of the light source used for exposure include a low pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, and an argon gas laser. The amount of radiation exposure varies depending on the type and amount of each component in the resin composition, the thickness of the photosensitive layer, and the like, but is usually 1000 to 15000 J / m ² when using a high-pressure mercury lamp, for example.

3. Development method Using an alkaline aqueous solution as a developer, an unnecessary non-exposed portion in the photosensitive layer after radiation exposure is dissolved and removed, and only the exposed portion is left to develop the photosensitive layer, thereby forming a predetermined resist pattern. Obtainable.

  Examples of the developer include sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, sodium metasilicate, aqueous ammonia, ethylamine, n-propylamine, diethylamine, di-n-propylamine, triethylamine, and methyldiethylamine. , Dimethylethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, pyrrole, piperidine, 1,8-diazabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4.3. 0] -5-nonane.

Further, an aqueous solution obtained by adding an appropriate amount of a water-soluble organic solvent such as methanol or ethanol or a surfactant to the alkaline aqueous solution can also be used as a developer.
The development time varies depending on the type of each component in the resin composition, the blending ratio, the thickness of the photosensitive layer, and the like, but is usually 30 to 360 seconds. Examples of the developing method include a liquid filling method, a dipping method, a paddle method, a spray method, and a shower developing method. After the development, washing with running water is performed for 30 to 90 seconds, and air drying is performed using an air gun or the like, or drying is performed using a hot plate, an oven, or the like.

4). Post-treatment The photosensitive layer comprising the negative radiation-sensitive resin composition of the present invention can be sufficiently cured only by the above-mentioned radiation exposure, but depending on the application, additional radiation exposure (hereinafter referred to as “post-exposure”) And can be further cured by heating. By this post-treatment, a predetermined resist pattern having even better characteristics can be obtained.

The post-exposure can be performed by the same method as the above-described radiation exposure method, and the radiation exposure amount is not particularly limited, but is preferably 1000 to 20000 J / m ² when a high-pressure mercury lamp is used.

  Moreover, as heat processing, using heating apparatuses, such as a hotplate and an oven, at predetermined temperature (for example, 60-100 degreeC), for predetermined time (for example, 5-30 minutes on a hotplate, 5-5 in oven). 60 minutes).

5. Plating treatment A substrate on which a predetermined resist pattern has been formed is immersed in various plating solutions for electroplating, and plating is performed by setting the current value and energizing time so that the desired plating thickness is obtained, thereby forming a plated model. To do.

6). Stripping process The resist pattern is stripped from the plated substrate. As a peeling method, for example, the substrate may be immersed in a peeling solution being stirred at 50 to 80 ° C. for 5 to 30 minutes. Examples of the stripping solution include an aqueous solution of a quaternary ammonium salt, and a mixed solution of a quaternary ammonium salt, dimethyl sulfoxide, and water.

  By carrying out the above series of steps, a plated model can be formed on the substrate. And the resist pattern formed from the negative radiation sensitive resin composition of this invention is excellent in the peelability after plating modeling object formation.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, “parts” means parts by weight, and “%” means wt%.
[Synthesis Example 1]
In a flask equipped with a nitrogen-substituted dry ice / methanol refluxer, 2,2′-azobisisobutyronitrile (5.0 g) as a radical polymerization initiator and dipropylene glycol methyl ether acetate (150 g) as a polymerization solvent. ) And stirred until the polymerization initiator was dissolved.

  To the resulting solution, α-methyl-p-hydroxystyrene (30 g), methacrylic acid (12 g), isobornyl acrylate (29 g), and n-butyl acrylate (29 g) are charged, and the solid content is completely dissolved. Until stirred.

  The temperature of the obtained solution was raised to 80 ° C., and polymerization was carried out at this temperature for 7 hours. Thereafter, the temperature of the solution was raised to 100 ° C., and polymerization was performed at this temperature for 1 hour to obtain a reaction solution containing the alkali-soluble copolymer (A1).

[Synthesis Examples 2 to 5]
In Synthesis Example 1, alkali-soluble copolymers (A2), (A3), (CA1) and (CA2) were prepared in the same manner as in Synthesis Example 1 except that the types and amounts of the compounds were changed according to the composition described in Table 1. ) Was synthesized.

［実施例１］
アルカリ可溶性共重合体（Ａ）として、〔合成例１〕で得られた上記共重合体（Ａ１）（１００ｇ）、架橋剤類（Ｂ）として、ジペンタエリスリトールヘキサアクリレート（日本化薬（株）社製、商品名「ＫＡＹＡＲＡＤ ＤＰＨＡ」）（５０ｇ）、ペンタエリスリトールポリアクリレート（新中村化学工業（株）社製、商品名「ＮＫエステルＡ−ＴＭＭ−３ＬＭ−Ｎ」）（１０ｇ）、感放射線性ラジカル重合開始剤（Ｃ）として、２，４，６−トリメチルベンゾイルジフェニルホスフィンオキサイド（１２ｇ）、２−ベンジル−２−ジメチルアミノ−１−（４−モルフォリノフェニル）−ブタン−１−オン（１ｇ）、溶剤（Ｄ）として、ジプロピレングリコールメチルエーテルアセテート（１５０ｇ）、および界面活性剤として、ジグリセリンエチレンオキサイド（平均付加モル数＝１８）付加物ペルフルオロノネニルエーテル(（株）ネオス社製、商品名「フタージェントＦＴＸ−２
１８」）（０．３ｇ）を混合し、攪拌して均一な組成物溶液を調製した。この組成物溶液
を、孔径１０μｍのカプセルフィルターでろ過して感放射線性樹脂組成物を得た。

[Example 1]
As the alkali-soluble copolymer (A), the copolymer (A1) (100 g) obtained in [Synthesis Example 1], and as the crosslinking agents (B), dipentaerythritol hexaacrylate (Nippon Kayaku Co., Ltd.) (Trade name “KAYARAD DPHA”) (50 g), pentaerythritol polyacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-TMM-3LM-N”) (10 g), radiation sensitivity As the radical polymerization initiator (C), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (12 g), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one (1 g) ), Dipropylene glycol methyl ether acetate (150 g) as solvent (D), and diglycerin as surfactant Ethylene oxide (average number of moles added = 18) adduct perfluorononenyl ether (manufactured by Neos Co., Ltd., trade name “Furgent FTX-2”)
18 ") (0.3 g) was mixed and stirred to prepare a uniform composition solution. This composition solution was filtered through a capsule filter having a pore diameter of 10 μm to obtain a radiation sensitive resin composition.

[Examples 2-8, Comparative Examples 1-3]
Example 1 is the same as Example 1 except that the types and amounts of the alkali-soluble copolymer, the crosslinking agents (B) and the radiation-sensitive radical polymerization initiator (C) are changed according to the composition described in Table 2. Thus, a radiation sensitive resin composition was prepared.

[Evaluation]
Using the radiation sensitive resin compositions obtained in Examples 1 to 8 and Comparative Examples 1 to 3, a resist pattern and a plated model are formed by the following method, and the resolution and peelability of the resist pattern are evaluated. It was. The results are shown in Table 2.

(1) Formation of resist pattern After applying the radiation-sensitive resin composition to a glass epoxy copper-clad substrate obtained by laminating a copper foil having a thickness of 35 µm using a roll coater, it is performed in a hot air oven at 70 ° C for 50 minutes. A photosensitive layer having a thickness of 20 μm was formed by heating.

Next, L / S pattern = 3/3, 4/4, 5/5, 6/6, 7/7, 8/8, 9/9, 10/10, 15/15, 20/20, 25/25 The photosensitive layer was irradiated with ultraviolet light of 300 to 1000 mJ / cm ² through a pattern mask having 30/30 μm (design dimension) using an ultrahigh pressure mercury lamp (HBO manufactured by OSRAM, output 1000 W). The exposure amount was confirmed with an illuminometer (an apparatus in which a probe UV-42 (light receiver) was connected to UV-M10 (illuminometer) manufactured by Oak Manufacturing Co., Ltd.)).

  Next, the exposed photosensitive layer was developed at room temperature using a 0.3% aqueous sodium hydroxide solution as a developing solution, washed with running water, and blown with nitrogen to form a resist pattern. Hereinafter, the substrate on which the resist pattern is formed is referred to as a “patterning substrate”.

(2) Formation of plated modeled object The patterning substrate was subjected to electrolytic copper plating at 25 ° C., 3 A / dm ² for 25 minutes using Microfab Cu200 (manufactured by Nippon Electroplating Engineers Co., Ltd.) as a plating solution. A wiring with a height of 15 μm was formed.

  Next, a 5% aqueous sodium hydroxide solution was used as a stripping solution, and the substrate was dipped while stirring at 60 ° C. for 6 minutes to strip the resist pattern, thereby obtaining a substrate having a plated model. Hereinafter, the substrate having the plated model is referred to as a “plated substrate”.

(3) Evaluation of resolution The resolution was evaluated by observing the patterning substrate with a scanning electron microscope at 1000 times. Here, the resolution means L / S pattern = 3/3, 4/4, 5/5, 6/6, 7/7, 8/8, 9/9, 10/10, 15/15, 20/20. , 25/25, 30/30 μm (design dimensions), the minimum dimension design in which a resist pattern can be formed without residue.

(4) Evaluation of peelability The peelability was evaluated by observing the plated substrate with a scanning electron microscope at 1500 times. Here, peelability means L / S pattern = 3/3, 4/4, 5/5, 6/6, 7/7, 8/8, 9/9, 10/10, 15/15, 20 / Of 20, 25/25, and 30/30 μm (design dimension), it means the minimum design dimension in which there is no residue and the resist pattern can be peeled off.

表２に示した各化合物の詳細を以下に示す。
Ｂ１：ジペンタエリスリトールヘキサアクリレート
（日本化薬（株）社製、商品名「ＫＡＹＡＲＡＤ ＤＰＨＡ」）
Ｂ２：ジペンタエリスリトールテトラアクリレート誘導体
（日本化薬（株）社製、商品名「ＫＡＹＡＲＡＤ ＤＰＨＡ−２０」）
Ｂ３：ペンタエリスリトールポリアクリレート
（新中村化学工業（株）社製、商品名「ＮＫエステルＡ−ＴＭＭ−３ＬＭ−Ｎ」）
Ｂ４：トリメチロールプロパントリアクリレート
（大阪有機化学工業（株）社製、商品名「ビスコート２９５」）
Ｂ５：ビスフェノールＡジアクリレート
（日本油脂（株）社製、「ブレンマーＡＤＢＥ−２００」）
Ｃ１：２，４，６−トリメチルベンゾイルジフェニルホスフィンオキサイド
Ｃ２：２−ベンジル−２−ジメチルアミノ−１−（４−モルフォリノフェニル）−ブタン−１−オン
Ｃ３：２，２'−ビス（２−クロロフェニル）−４，５，４'，５'−テトラフェニル−１
，２’−ビイミダゾール
Ｃ４：４，４'−ビス（ジエチルアミノ）ベンゾフェノン

Details of each compound shown in Table 2 are shown below.
B1: Dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name “KAYARAD DPHA”)
B2: Dipentaerythritol tetraacrylate derivative (manufactured by Nippon Kayaku Co., Ltd., trade name “KAYARAD DPHA-20”)
B3: Pentaerythritol polyacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-TMM-3LM-N”)
B4: Trimethylolpropane triacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name “Biscoat 295”)
B5: Bisphenol A diacrylate (Nippon Yushi Co., Ltd., “Blenmer ADBE-200”)
C1: 2,4,6-trimethylbenzoyldiphenylphosphine oxide C2: 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one C3: 2,2′-bis (2- Chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1
, 2′-biimidazole C4: 4,4′-bis (diethylamino) benzophenone

Claims (4)

(A) (a1) a structural unit derived from a radically polymerizable compound having a phenolic hydroxyl group, (a2) a structural unit derived from a radically polymerizable compound having a carboxyl group, and (a3) derived from another radically polymerizable compound An alkali-soluble copolymer having a structural unit
(B) A negative radiation sensitive resin composition comprising a crosslinking agent containing a crosslinking agent represented by the following formula (1), and (C) a radiation sensitive radical polymerization initiator.

[In the formula (1), X is an organic group represented by the following formula (2) or (3), and the six Xs may be the same or different.

In formula (2), n is an integer of 2 to 4, m is an integer of 0 to 10, and in formula (3), l is an integer of 0 to 2. In formulas (2) and (3), R represents a hydrogen atom or a (meth) acryloyl group. However, the crosslinking agent represented by the formula (1) has at least four (meth) acryloyl groups. ]   The negative radiation-sensitive resin composition according to claim 1, wherein the radically polymerizable compound having a phenolic hydroxyl group is α-methyl-p-hydroxystyrene.   The negative radiation-sensitive resin composition according to claim 1 or 2, wherein the crosslinking agent represented by the formula (1) is dipentaerythritol hexaacrylate. When the total structural unit of the alkali-soluble copolymer (A) is 100% by weight,
The content of the structural unit derived from the radically polymerizable compound having (a1) phenolic hydroxyl group is 1 to 50% by weight,
The content of the structural unit derived from the radical polymerizable compound having a carboxyl group (a2) is 1 to 50% by weight,
The negative radiation-sensitive resin composition according to any one of claims 1 to 3, wherein the content of the structural unit derived from (a3) another radical polymerizable compound is 5 to 80% by weight. .