JP2010117545A - Photosensitive resin composition and application thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition with high developing solution dispersion stability, not generating agglomerate, and having high edge phase property, high trackability, and high plating resistance, a photosensitive resin laminated body having a photosensitive resin layer made of the composition, a forming method of a resist pattern using the laminated body, and a method of manufacturing a conductive pattern. <P>SOLUTION: The photosensitive resin composition contains (a) 20 to 90 mass% alkali soluble polymer where carboxyl group content is 100 to 550 in acid equivalent and weight-average molecular weight is 5,000 to 500,000, (b) 3 to 70 mass% ethylene based addition polymerization monomer, (c) 0.1 to 20 mass% specific 2,4,5-triallyl imidazole dimer, and (d) 1.0-15 mass%phosphoric acid allyl compound represented by general formula (III). <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a photosensitive resin composition and use thereof, and in particular, a photosensitive resin laminate suitable for manufacturing a conductive pattern such as a printed wiring board and a lead frame including a rigid board and a flexible board, and a resist using the same. The present invention relates to a pattern forming method, a conductor pattern manufacturing method, a printed wiring board manufacturing method, a semiconductor package manufacturing method, a lead frame manufacturing method, and a concavo-convex substrate manufacturing method.

For electronic devices such as personal computers and mobile phones, printed wiring boards and the like are used for mounting components and semiconductors. Conventionally, as a resist for manufacturing a printed wiring board or the like, a so-called dry film resist in which a support, a photosensitive resin layer, and a protective layer as necessary are further laminated is used. The dry film resist is generally prepared by laminating a photosensitive resin layer on a support, and further laminating a protective layer on the photosensitive resin layer as necessary. As the photosensitive resin layer used here, an alkali developing type using a weak alkaline aqueous solution as a developing solution is generally used.
To fabricate a printed wiring board using a dry film resist, first peel off the protective layer, and then laminate the dry film resist on a permanent circuit fabrication substrate such as a copper-clad laminate or a flexible substrate using a laminator or the like. If necessary, the support is peeled off and exposed through a wiring pattern mask film or the like. Next, if there is a support, it is peeled off, and the photosensitive resin layer in the unexposed part is dissolved or dispersed and removed by a developer to form a resist pattern on the substrate.

  After forming the resist pattern, the process for forming a circuit is roughly divided into two methods. The first method is a method in which after removing a copper surface such as a copper clad laminate not covered with a resist pattern by etching, the resist pattern portion is removed with an alkaline aqueous solution stronger than the developer. In this case, for simplicity of the process, a method (tenting method) in which a through hole (through hole) is covered with a cured film and then etched is frequently used. In the second method, after plating the copper surface with copper, solder, nickel, tin, etc., the resist pattern portion is similarly removed, and the copper surface of the copper clad laminate, etc. that appears is etched. In this method, the plating is peeled off (plating method). In any case, cupric chloride, ferric chloride, a copper ammonia complex solution or the like is used for etching.

In recent printed wiring boards, high resolution of resists is required for higher integration of wiring.
The resist pattern used for the plating method needs to be resistant to the plating solution. If the plating resistance is weak, the resist pattern is lifted from the substrate during the immersion of the chemical solution, and the plating solution is trapped under the resist pattern, thereby causing a short-circuit or rattling of the conductor pattern. Therefore, the resist used in the plating method needs to be resistant to the plating solution.
The step of dissolving or dispersing and removing the photosensitive resin layer in the unexposed portion with a developer after exposure is called a development step. Not all of the dry film resist components dissolve in the developer, and the developer is recycled. Therefore, each time the development process is repeated, insoluble components with poor developer dispersibility increase and aggregates (scum) ). Aggregates re-adhere on the substrate, causing a short circuit failure in the tenting and etching methods, and may clog the developing tank piping. Therefore, there is a need for a dry film resist that reduces aggregates during development.

Accordingly, there has been a demand for a photosensitive resin composition having high resolution, excellent developer dispersion stability in the development process, and does not generate aggregates, and has high plating resistance.
For the purpose of reducing aggregates during development, Patent Document 1 discloses an attempt to use an alkylphenol type monofunctional monomer having good developer dispersion as a photopolymerizable unsaturated compound, and Patent Document 2 discloses a phenoxy type monofunctional compound. There are disclosures of attempts to use monomers, but none of them satisfied the current situation.
Patent Document 3 discloses a propylene glycol-modified monofunctional monomer as a photopolymerizable unsaturated compound for the purpose of improving plating resistance, but is a photosensitive resin composition that has excellent developer dispersion stability and does not generate aggregates. There was no disclosure.
Patent Document 4 discloses a phosphate ester as a plasticizer component, but does not disclose a photosensitive resin composition excellent in development aggregation.
JP 2001-174986 A JP 2001-305730 A JP 2000-231190 A JP 2006-145565 A

    The present invention has a photosensitive resin composition that has high resolution, excellent developer dispersion stability, does not generate aggregates, has high plating resistance, and a photosensitive resin layer containing the composition. It is an object of the present invention to provide a photosensitive resin laminate, and to provide a method for forming a resist pattern using the laminate and a method for producing a conductor pattern and the like.

As a result of studying to solve the above problems, by using a specific photosensitive resin composition, it has high resolution, excellent developer dispersion stability, does not generate aggregates, and has high plating resistance. As a result, the present invention has been found.
That is, the present invention is as follows.
[1]
(A) Alkali-soluble polymer having a carboxyl group content of 100 to 550 in terms of acid equivalent and a weight average molecular weight of 5,000 to 500,000: 20 to 90% by mass, (b) ethylenic addition polymerization monomer: 3 to 3 70% by mass, (c) 2,4,5-triarylimidazole dimer represented by the following general formula (I) or (II): 0.1 to 20% by mass, and (d) the following general A photosensitive resin composition comprising an allyl phosphate compound represented by formula (III): 1.0 to 15% by mass.

(In the formula, A ₁ , A ₂ , and A ₃ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms and an alkoxy group, or a halogen atom, and p, q, and r are each independently 1 to 5 are integers.

(In the formula, B ₁ represents any _one of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and an alkoxy group, or a halogen atom, and B ₂ represents any one of an alkyl group having 1 to 10 carbon atoms and an allyl group. And p is an integer of 1 to 3, and q is an integer of 1 to 5.)
[2]
In the above [1], the content of the 2,4,5-triarylimidazole dimer represented by the above general formula (I) or (II) is 2.0 to 20% by mass. The photosensitive resin composition as described.
[3]
Furthermore, (e) The alkylene oxide compound represented by the following general formula (IV): The photosensitive resin composition as described in said [1] or [2] containing 1-30 mass%.

(In the formula, n is an integer of 4 to 100, R ₁ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ₂ and R ₃ are each independently a hydrogen atom, a methacrylic acid ester, or an acrylic acid ester. )
[4]
The photosensitive resin laminated body by which the photosensitive resin composition layer in which the photosensitive resin composition as described in any one of said [1] to [3] contained, and the support body were laminated | stacked.
[5]
A method for forming a resist pattern, comprising: laminating the photosensitive resin laminate of [4] above on a substrate, exposing to ultraviolet rays, and then removing unexposed portions by development.
[6]
In the exposure step, the resist pattern forming method as described in [5], wherein the exposure is performed without using a photomask.
[7]
A method for producing a conductor pattern, comprising using a metal plate or a metal-coated insulating plate as a substrate, and etching or plating a substrate on which a resist pattern is formed by the method described in [5] or [6].
[8]
A method for producing a printed wiring board comprising: using a metal-coated insulating plate as a substrate; etching or plating a substrate on which a resist pattern is formed by the method according to [5] or [6]; and peeling the resist pattern .
[9]
A method for producing a lead frame, comprising: using a metal plate as a substrate; etching a substrate on which a resist pattern is formed by the method described in [5] or [6] above; and removing the resist pattern.
[10]
A semiconductor package characterized by using a wafer on which circuit formation as an LSI has been completed as a substrate, plating a substrate on which a resist pattern has been formed by the method described in [5] or [6] above, and peeling the resist pattern Manufacturing method.
[11]
Manufacture of a substrate having a concavo-convex pattern, characterized in that a glass rib is used as a substrate, a substrate on which a resist pattern is formed by the method described in [5] or [6] is processed by a sandblasting method, and the resist pattern is peeled off. Method.

  According to the present invention, the photosensitive resin composition having high resolution, excellent dispersion stability of the developing solution in the development process, and does not generate aggregates, and has high plating resistance, and the composition. A photosensitive resin laminate having a photosensitive resin layer can be provided.

Hereinafter, the present invention will be specifically described.
<Photosensitive resin composition>
The (a) alkali-soluble polymer used in the present invention has a carboxyl group content of 100 to 550 in terms of acid equivalent and a weight average molecular weight of 5,000 to 500,000.
(A) The carboxyl group of the alkali-soluble polymer is necessary to give the photosensitive resin layer developability and peelability with respect to an aqueous alkali solution, and the content thereof is from 100 to 550 in terms of acid equivalent. An acid equivalent means the mass of the linear polymer which has a 1 equivalent carboxyl group in it. The acid equivalent is 100 or more, and preferably 250 or more, from the viewpoint of development resistance, resolution, and adhesion. From the viewpoint of developability and peelability, it is 550 or less, preferably 450 or less. The acid equivalent is measured by a potentiometric titration method using a Hiranuma automatic titrator (COM-555) manufactured by Hiranuma Sangyo Co., Ltd., and using a 0.1 mol / L sodium hydroxide aqueous solution.

(A) The weight average molecular weight of the alkali-soluble polymer is 5,000 to 500,000. The weight average molecular weight of the alkali-soluble polymer is 500,000 or less from the viewpoint of resolution, and is 5,000 or more from the viewpoint of edge fuse. In order to further exert the effect of the present invention, the weight average molecular weight of the alkali-soluble polymer is more preferably 5,000 to 200,000, and further preferably 5,000 to 100,000.
The weight average molecular weight was measured by Gel Permeation Chromatography (GPC) manufactured by JASCO Corporation (pump: GullIver, PU-1580 type, column: Shodex (registered trademark) manufactured by Showa Denko KK (KF-807, KF-806M). , KF-806M, KF-802.5) in series, moving bed solvent: tetrahydrofuran, polystyrene standard sample (use of calibration curve by Shodex STANDARD SM-105 Polystyrene manufactured by Showa Denko K.K.) ).

(A) The alkali-soluble polymer is obtained by copolymerizing at least one monomer from the following first or second monomers. The content of the first monomer is determined by the acid equivalent. Further, the following second monomer may be copolymerized as necessary.
The first monomer is a carboxylic acid or acid anhydride having one polymerizable unsaturated group in the molecule. Examples include (meth) acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, maleic acid half ester, and the like.

  The second monomer is a non-acidic compound having one polymerizable unsaturated group in the molecule. The compound is selected so as to maintain various properties such as developability of the photosensitive resin layer, resistance in etching and plating processes, and flexibility of the cured film. Examples of the compound include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2 -Hydroxypropyl (meth) acrylate, (meth) acrylonitrile, furfuryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, phenoxyethyl (meth) acrylate, phenyl (meth) acrylate, cresyl (meth) acrylate, naphthyl (meth) Aryl (meth) acrylates such as acrylate, vinyl compounds having a phenyl group (for example, styrene), benzyl (meth) acrylate, methoxybenzyl (meth) acrylate and chlorobenzyl Meth) benzyl (meth) aromatic ring alkoxy groups acrylates such as acrylates, halogen, alkyl group can be used compounds obtained by substituting. Among these, styrene and butyl acrylate are preferable from the viewpoints of high resolution and plating resistance.

(A) The alkali-soluble polymer is obtained by adding a mixture of the first monomer and, if necessary, the second monomer to a solution diluted with a solvent such as acetone, methyl ethyl ketone, or isopropanol. It is preferable to carry out the synthesis by adding an appropriate amount of a radical polymerization initiator such as benzoyl oxide or azoisobutyronitrile and stirring with heating. In some cases, the synthesis is performed while a part of the mixture is dropped into the reaction solution. After completion of the reaction, a solvent may be further added to adjust to a desired concentration. As synthesis means, bulk polymerization, suspension polymerization, or emulsion polymerization may be used in addition to solution polymerization.
(A) The ratio of the alkali-soluble polymer to the total of the photosensitive resin composition is in the range of 20 to 90% by mass, preferably 30 to 70% by mass. The resist pattern formed by exposure and development is in the range of 20% by mass or more and 90% by mass or less from the viewpoint that the resist pattern has sufficient characteristics such as resisting, eg, tenting, etching, and various plating processes.

  In the photosensitive resin composition, the following compounds can be used as the (b) ethylenic addition polymerization monomer. For example, 1,6-hexanediol di (meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 2-di (p-hydroxyphenyl) propanedi (meth) acrylate , Glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyoxypropyltrimethylolpropane tri (meth) acrylate, polyoxyethyltrimethylolpropane triacrylate, pentaerythritol tetra (meth) acrylate, dipenta Erythritol penta (meth) acrylate, trimethylolpropane triglycidyl ether tertri (meth) acrylate, bisphenol A diglycidyl ether terdi (meth) acrylate, β-hydro Cypropyl-β ′-(acryloyloxy) propyl phthalate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyalkylene glycol (meth) acrylate, 2,2-bis {(4- (Meth) acryloxypolyethoxy) cyclohexyl} propane, propylene oxide-added polypropylene glycol with polyoxyalkylene glycol dimethacrylate with both ends added, propylene oxide in the molecule of bisphenol A (meth) acrylate monomer A compound containing a chain, a compound containing an ethylene oxide chain in the molecule of a bisphenol A (meth) acrylate monomer, and a bisphenol A ( Data) compounds containing both ethylene oxide chain and a propylene oxide chain and the like in the molecule of the acrylate monomer.

Moreover, a urethane compound is also mentioned. Examples of the urethane compound include a diisocyanate compound such as hexamethylene diisocyanate, tolylene diisocyanate, or 2,2,4-trimethylhexamethylene diisocyanate, and hydroxyl group in one molecule. And urethane compounds obtained by reaction of a group with a compound having a (meth) acryl group (such as 2-hydroxypropyl acrylate and oligopropylene glycol monomethacrylate). Specifically, there is a reaction product of hexamethylene diisocyanate and oligopropylene glycol monomethacrylate (manufactured by NOF Corporation, Bremma-PP1000).
(B) The ratio of the ethylenic addition polymerization monomer to the total of the photosensitive resin composition is 3% by mass or more from the viewpoint of sensitivity, and is 70% by mass or less from the viewpoint of edge fuse. More preferably, it is 10-65 mass%, More preferably, it is 15-55 mass%.

  It is a preferred embodiment from the viewpoint of resolution that the photopolymerization initiator contains (c) a 2,4,5-triary-imidazole dimer represented by the following general formula (I) or (II). .

（式中、Ａ１、Ａ２、及びＡ３はそれぞれ独立に水素、炭素数１から５のアルキル基及びアルコキシ基、並びにハロゲン原子のいずれかを表し、ｐ、ｑ、及びｒはそれぞれ独立に１〜５の整数である。）
上記一般式（Ｉ）又は（ＩＩ）で表される化合物においては、２個のロフィン基を結合する共有結合は、１，１’−、１，２’−、１，４’−、２，２’−、２，４’−又は４，４’−位についているが、１，２’−位についている化合物が好ましい。 ２，４，５−トリアリ−ルイミダゾ−ル二量体には、例えば、２−（ｏ−クロロフェニル）−４，５−ジフェニルイミダゾ−ル二量体、２−（ｏ−クロロフェニル）−４，５−ビス−（ｍ−メトキシフェニル）イミダゾ−ル二量体、２−（ｐ−メトシキフェニル）−４，５−ジフェニルイミダゾ−ル二量体等があるが、特に、２−（ｏ−クロロフェニル）−４，５−ジフェニルイミダゾ−ル二量体が好ましい。

(In the formula, A1, A2, and A3 each independently represent hydrogen, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, or a halogen atom, and p, q, and r each independently represent 1 to 5) Is an integer.)
In the compound represented by the above general formula (I) or (II), the covalent bond connecting two lophine groups is 1,1′-, 1,2′-, 1,4′-, 2, It is in the 2'-, 2,4'- or 4,4'-position, but compounds in the 1,2'-position are preferred. Examples of 2,4,5-triarylimidazole dimers include 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5. -Bis- (m-methoxyphenyl) imidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, etc., and in particular, 2- (o-chlorophenyl) ) -4,5-diphenylimidazole dimer is preferred.

As the photopolymerization initiator, a system in which the aforementioned 2,4,5-triarylimidazol dimer and p-aminophenyl ketone are used in combination is preferable. Examples of p-aminophenyl ketone include p-aminobenzophenone, p-butylaminoacetophenone, p-dimethylaminoacetophenone, p-dimethylaminobenzophenone, p, p'-bis (ethylamino) benzophenone, p, p'- Bis (dimethylamino) benzophenone [Michler's ketone], p, p′-bis (diethylamino) benzophenone, p, p′-bis (dibutylamino) benzophenone, and the like.
A combination with a pyrazoline compound such as 1-phenyl-3- (4-tert-butyl-styryl) -5- (4-tert-butyl-phenyl) -pyrazoline is also a preferred embodiment.

In addition to the compounds shown above, other photopolymerization initiators can be used in combination. Here, the photopolymerization initiator is a compound that is activated by various actinic rays such as ultraviolet rays and starts polymerization.
Other photopolymerization initiators include, for example, quinones such as 2-ethylanthraquinone and 2-tert-butylanthraquinone, aromatic ketones such as benzophenone, benzoin ethers such as benzoin, benzoin methyl ether and benzoin ethyl ether, Examples include acridine compounds such as 9-phenylacridine, benzyldimethylketal, and benzyldiethylketal.

Further, for example, there are combinations of thioxanthones such as thioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and tertiary amine compounds such as dimethylaminobenzoic acid alkyl ester compounds.
Further, there are oxime esters such as 1-phenyl-1,2-propanedione-2-O-benzoyloxime and 1-phenyl-1,2-propanedione-2- (O-ethoxycarbonyl) oxime. Further, N-aryl-α-amino acid compounds can also be used, and among these, N-phenylglycine is particularly preferable.

In the photosensitive resin composition, the content ratio of (c) 2,4,5-triary-imidazole dimer is 0.1 to 20% by mass. From the viewpoint of sensitivity, it is 0.1% by mass or more, and from the viewpoint of resolution, it is 20% by mass or less. The content is more preferably 0.1 to 15% by mass, still more preferably 1 to 10% by mass, and most preferably 2.0 to 5.0% by mass.
As for the ratio of a photoinitiator, 0.1-20 mass% is preferable with respect to the sum total of the photosensitive resin composition. 0.1 mass% or more is preferable from the viewpoint of sensitivity, and 20 mass% or less is preferable from the viewpoint of resolution. As for content, 0.1-15 mass% is more preferable, and 0.1-10 mass% is still more preferable.

  The photosensitive resin composition contains (d) an allyl phosphate compound represented by the following general formula (III). (D) An allyl phosphate compound is an esterified product of phosphoric acid and an aromatic alcohol compound, and is produced by ester reaction of one to three of the three hydroxyl groups in phosphoric acid. From the viewpoints of low aggregation and image formation (high resolution), a triester compound in which all three hydroxyl groups are substituted is preferred, and triphenyl phosphate is more preferred. (D) The allyl phosphate compound is usually added to the resin for the purpose of imparting flexibility, but the effect on the development aggregation property is not disclosed. In the present invention, a development aggregate derived from a 2,4,5-triarylimidazole dimer and a development derived from a propylene oxide compound are used in combination with the above general formulas (I) or (II) and (III). It has been found that there is an effect of reducing aggregates.

（式中、Ｂ_１は水素、炭素数１から１０のアルキル基及びアルコキシ基、並びにハロゲン原子のいずれかを表し、Ｂ_２は炭素数１から１０のアルキル基、並びにアリル基のいずれかを表し、ｐは１〜３の整数、ｑは１〜５の整数である。）
上記一般式（ＩＩＩ）で表されるリン酸アリル化合物の具体例としては、トリフェニルホスフェート、トリクレジルホスフェート、クレジルジフェニルホスフェート、オクチルジフェニルホスフェートが挙げられる。これらの中で特にトリフェニルホスフェートが好ましい。

(In the formula, B ₁ represents any _one of hydrogen, an alkyl group having 1 to 10 carbon atoms and an alkoxy group, and a halogen atom, and B ₂ represents any one of an alkyl group having 1 to 10 carbon atoms and an allyl group. And p is an integer of 1 to 3, and q is an integer of 1 to 5.)
Specific examples of the allyl phosphate compound represented by the general formula (III) include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, and octyl diphenyl phosphate. Of these, triphenyl phosphate is particularly preferred.

(D) Content of the allyl phosphate compound with respect to the total of the photosensitive resin composition is 1.0 to 15% by mass. From the viewpoint of development aggregation, it is 1.0% by mass or more, and from the point of sensitivity, it is 15% by mass or less. Preferably it is 1.0-10 mass%, More preferably, it is 1.0-8 mass%.
In the photosensitive resin composition, it is a preferable form to contain a compound represented by the following general formula (IV).

（式中、ｎは４〜１００の整数、Ｒ_１は水素または炭素数１〜５のアルキル基、Ｒ_２およびＲ_３はそれぞれ独立に水素、メタクリル酸エステル、アクリル酸エステルである）
上記一般式（ＩＶ）で表される化合物において、ｎは４〜１００であり、コールドフロー性の観点からｎは４以上が好ましく、解像度、現像凝集性の観点からｎは１００以下が好ましい。より好ましくは、ｎは４以上５０以下である。上記一般式（ＩＶ）で表される化合物の具体的な例としては、ポリプロピレングリコ−ルジ（メタ）アクリレート、ポリプロピレングリコールモノ（メタ）アクリレート、ポリプロピレングリコールであり、例えば日油（株）のユニオールＤ −４００ （重量分子量：４００ ）、Ｄ −２０００ （重量分子量：２０００ ）、ノナプロピレングリコールジメタクリレートなどが挙げられる。

(In the formula, n is an integer of 4 to 100, R ₁ is hydrogen or an alkyl group having 1 to 5 carbon atoms, and R ₂ and R ₃ are each independently hydrogen, methacrylate ester, or acrylate ester)
In the compound represented by the general formula (IV), n is 4 to 100, n is preferably 4 or more from the viewpoint of cold flow property, and n is preferably 100 or less from the viewpoint of resolution and development aggregation. More preferably, n is 4 or more and 50 or less. Specific examples of the compound represented by the general formula (IV) include polypropylene glycol di (meth) acrylate, polypropylene glycol mono (meth) acrylate, and polypropylene glycol. For example, Uniol D of NOF Corporation. -400 (weight molecular weight: 400), D-2000 (weight molecular weight: 2000), nonapropylene glycol dimethacrylate and the like.

Furthermore, you may make the photosensitive resin composition contain plasticizers other than the said general formula (IV) as needed. Examples of the plasticizer include phthalic acid esters such as diethyl phthalate, o-toluenesulfonic acid amide, p-toluenesulfonic acid amide, tributyl citrate, triethyl citrate, acetyl triethyl citrate, and acetyl tricitrate tri-n-propyl. Acetyl citrate tri-n-butyl, polyethylene glycol, polyethylene glycol alkyl ether, polypropylene glycol alkyl ether, and the like. In particular, p-toluenesulfonic acid amide is preferable.
As content in the case of containing a plasticizer etc., it is preferable to contain 5-50 mass% in a photosensitive resin composition, More preferably, it is 5-30 mass%. 5 mass% or more is preferable from the viewpoint of suppressing delay in development time and imparting flexibility to the cured film, and 50 mass% or less is preferable from the viewpoint of suppressing insufficient curing and cold flow.

  The photosensitive resin composition may contain a coloring substance. Examples of such coloring substances include fuchsin, phthalocyanine green, auramin base, chalcoxide green S, paramagenta, crystal violet, methyl orange, nile blue 2B, Victoria blue, malachite green, basic blue 20, and diamond green. Can be mentioned. When the photosensitive resin composition contains the above-described coloring substance, the content of the coloring substance with respect to the entire photosensitive resin composition is preferably in the range of 0.005 to 10% by mass, and 0.01 to 1% by mass. More preferably, it is in the range. From the viewpoint of resist visibility, the content of the coloring substance with respect to the entire photosensitive resin composition is preferably 0.005% by mass or more, and preferably 10% by mass or less from the viewpoint of sensitivity.

  Further, the photosensitive resin composition may contain a coloring dye that develops color by light irradiation. As such a coloring dye, a combination of a leuco dye and a halogen compound is well known. Examples of the leuco dye include tris (4-dimethylaminophenyl) methane [leuco crystal violet], bis (4-dimethylaminophenyl) phenylmethane [leucomalachite green], and the like. On the other hand, examples of the halogen compound include amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzal bromide, methylene bromide, tribromomethylphenyl sulfone, carbon tetrabromide, tris ( 2,3-dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,2-bis (p-chlorophenyl) ethane, hexachloroethane.

Furthermore, in order to improve the thermal stability and storage stability of the photosensitive resin composition, it is preferable that the photosensitive resin composition contains a radical polymerization inhibitor and benzotriazoles.
Examples of such radical polymerization inhibitors include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2 Examples include '-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), nitrosophenylhydroxyamine aluminum salt, and diphenylnitrosamine.

Examples of benzotriazoles include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, and bis (N-2-ethylhexyl) aminomethylene-1,2,3-benzo. Triazole, bis (N-2-ethylhexyl) aminomethylene-1,2,3-tolyltriazole, bis (N-2-hydroxyethyl) aminomethylene-1,2,3-benzotriazole, 4-carboxy-1,2 , 3-benzotriazole, 5-carboxy-1,2,3-benzotriazole.
The total content when the radical polymerization inhibitor and benzotriazoles are contained in the photosensitive resin composition is preferably 0.01 to 3% by mass, more preferably 0.05 to 1% by mass. This amount is preferably 0.01% by mass or more from the viewpoint of imparting storage stability to the photosensitive resin composition, and is preferably 3% by mass or less from the viewpoint of maintaining sensitivity.
These radical polymerization inhibitors and benzotriazole compounds may be used alone or in combination of two or more.

<Photosensitive resin laminate>
The photosensitive resin laminate of the present invention comprises a photosensitive resin layer and a support that supports the layer. If necessary, the photosensitive resin laminate may have a protective layer on the surface opposite to the support of the photosensitive resin layer. good. The support used here is preferably a transparent one that transmits light emitted from the exposure light source. Examples of such a support include polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film. , Polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film and the like. These films can be stretched if necessary. The haze is preferably 5 or less. The thinner the film, the more advantageous in terms of image forming property and economic efficiency, but a film having a thickness of 10 to 30 μm is preferably used because of the necessity of maintaining the strength.

Further, an important characteristic of the protective layer used in the photosensitive resin laminate is that the protective layer is sufficiently smaller than the support and can be easily peeled with respect to the adhesion with the photosensitive resin layer. For example, a polyethylene film or a polypropylene film can be preferably used as the protective layer. Also, a film having excellent peelability disclosed in JP-A-59-202457 can be used.
The thickness of the protective layer is preferably 10 to 100 μm, and more preferably 10 to 50 μm.
Although the thickness of the photosensitive resin layer in the photosensitive resin laminate of the present invention varies depending on the application, it is preferably 5 to 100 μm, more preferably 7 to 60 μm. The thinner the resolution, the better the resolution. The film strength is improved.

A conventionally known method can be adopted as a method for producing the photosensitive resin laminate of the present invention. For example, the photosensitive resin composition used for the photosensitive resin layer is mixed with a solvent that dissolves them to form a uniform solution, and is first coated on a support using a bar coater or roll coater, dried, and then supported. A photosensitive resin layer made of a photosensitive resin composition is laminated on the body. Next, if necessary, a photosensitive resin laminate can be produced by laminating a protective layer on the photosensitive resin layer.
Examples of the solvent include ketones represented by methyl ethyl ketone (MEK), and alcohols represented by methanol, ethanol, and isopropanol. It is preferable to add to the photosensitive resin composition so that the viscosity of the solution of the photosensitive resin composition applied onto the support is 500 to 4000 mPa · sec at 25 ° C.

<Resist pattern formation method>
A resist pattern using the photosensitive resin laminate can be formed by a process including a lamination process, an exposure process, and a development process. An example of a specific method is shown.
First, a lamination process is performed using a laminator. In the case where the photosensitive resin laminate has a protective layer, the protective layer is peeled off, and then the photosensitive resin layer is heat-pressed and laminated on the substrate surface with a laminator. In this case, the photosensitive resin layer may be laminated only on one side of the substrate surface or on both sides. The heating temperature at this time is generally 40 to 160 ° C. Moreover, adhesion and chemical resistance are improved by performing the thermocompression bonding twice or more. At this time, for the crimping, a two-stage laminator having two rolls may be used, or it may be repeatedly crimped through the roll several times.

Next, an exposure process is performed using an exposure machine. If necessary, the support is peeled off and exposed to active light through a photomask. The exposure amount is determined from the light source illuminance and the exposure time. You may measure using a photometer.
In the exposure process, a maskless exposure method may be used. In maskless exposure, exposure is performed by directly drawing on a substrate without using a photomask. As the light source, a semiconductor laser having a wavelength of 350 to 410 nm, an ultrahigh pressure mercury lamp, or the like is used. The drawing pattern is controlled by a computer, and the exposure amount in this case is determined by the light source illuminance and the moving speed of the substrate.

Next, a developing process is performed using a developing device. After the exposure, if there is a support on the photosensitive resin layer, it is removed if necessary, and then the unexposed portion is developed and removed using a developer of an alkaline aqueous solution to obtain a resist image. An aqueous solution of Na ₂ CO ₃ , K ₂ CO ₃ or the like is used as the alkaline aqueous solution. These are selected in accordance with the characteristics of the photosensitive resin layer, but a Na ₂ CO ₃ aqueous solution having a concentration of 0.2 to 2% by mass and 20 to 40 ° C. is generally used. A surface active agent, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like may be mixed in the alkaline aqueous solution.
Although a resist pattern is obtained by the above-mentioned process, a heating process at 100 to 300 ° C. can be further performed depending on the case. By carrying out this heating step, chemical resistance can be further improved. For heating, a heating furnace of a hot air, infrared ray, far infrared ray or the like is used.

<Conductor Pattern Manufacturing Method / Printed Wiring Board Manufacturing Method>
The method for producing a printed wiring board according to the present invention is performed through the following steps following the above-described resist pattern forming method using a copper clad laminate or a flexible substrate as a substrate. First, a conductor pattern is formed on the copper surface exposed by development using a known method such as an etching method or a plating method.
Thereafter, the resist pattern is peeled from the substrate with an aqueous solution having alkalinity stronger than that of the developer to obtain a desired printed wiring board. The alkaline aqueous solution for peeling (hereinafter also referred to as “peeling solution”) is not particularly limited, but an aqueous solution of NaOH or KOH at a concentration of 2 to 5% by mass, 40 to 70 ° C. is generally used. It is possible to add a small amount of a water-soluble solvent to the stripping solution.

<Lead frame manufacturing method>
The lead frame manufacturing method of the present invention is performed through the following steps following the above-described resist pattern forming method using a metal plate of copper, copper alloy, iron-based alloy or the like as a substrate.
First, a conductive pattern is formed by etching the substrate exposed by development. Thereafter, the resist pattern is peeled off by the same method as the above-described printed wiring board manufacturing method to obtain a desired lead frame.

<Semiconductor package manufacturing method>
The method for producing a semiconductor package of the present invention is performed by performing the following steps following the above-described resist pattern forming method using a wafer on which a circuit as an LSI has been formed as a substrate. A conductor pattern is formed by performing columnar plating such as copper or solder on the opening exposed by development. Thereafter, the resist pattern is peeled by the same method as the above-described printed wiring board manufacturing method, and the thin metal layer other than the columnar plating is removed by etching to obtain a desired semiconductor package.

<Manufacturing method of substrate having uneven pattern>
When processing the substrate by the sandblasting method using the photosensitive resin laminate of the present invention as a dry film resist, the photosensitive resin laminate is laminated on the substrate by the same method as described above, exposure, Develop. Further, the blast material is sprayed from the formed resist pattern to be cut to the desired depth, and the resin portion remaining on the substrate is removed from the substrate with an alkali stripping solution or the like. The pattern can be processed. As the blasting material used in the above sandblasting process, known materials are used. For example, fine particles of about ₂ to 100 μm such as SiC, SiO ₂ , Al ₂ O ₃ , CaCO ₃ , ZrO ₂ , glass, stainless steel, etc. are used.
Hereinafter, examples of embodiments of the present invention will be described in more detail by way of examples.

Below, the preparation method of the sample for evaluation of an Example and a comparative example, the evaluation method about the obtained sample, and an evaluation result are shown.
1. Production of Evaluation Sample The photosensitive resin laminates in Examples and Comparative Examples were produced as follows.
<Preparation of photosensitive resin laminate>
Prepare the compounds shown in Table 1, thoroughly stir and mix the photosensitive resin composition of the composition ratio shown in Table 2, and apply uniformly to the surface of a 20 μm thick polyethylene terephthalate film as a support using a bar coater, The photosensitive resin layer was formed by drying for 4 minutes in a dryer at 95 ° C. The thickness of the photosensitive resin layer was 40 μm.
In Tables 1 and 2, MEK represents methyl ethyl ketone, and the mass parts of B-1 to B-2 in Tables 1 and 2 are values including MEK.
Next, a 25 μm thick polyethylene film was laminated as a protective layer on the surface of the photosensitive resin layer on which the polyethylene terephthalate film was not laminated to obtain a photosensitive resin laminate.

<Board surface preparation>
2. (2), (4) The evaluation substrate was a 1.6 mm thick copper clad laminate on which 35 μm rolled copper foil was laminated, and the surface was wet buffol polished (manufactured by 3M Co., Ltd., Scotch Bright (registered trademark) HD. # 600 twice).
<Laminate>
While peeling the polyethylene film of the photosensitive resin laminate, it was laminated at a roll temperature of 105 ° C. with a hot roll laminator (Asahi Kasei Co., Ltd., AL-70) on a copper clad laminate that had been leveled and preheated to 60 ° C. . The air pressure was 0.35 MPa, and the laminating speed was 1.5 m / min.
<Exposure>
A mask film necessary for evaluation is placed on a polyethylene terephthalate film, which is a support, on a photosensitive resin layer, and a 21-step tablet made by Stöffer is 7 steps by an ultra-high pressure mercury lamp (OMW Seisakusho, HMW-201KB). The exposure amount was as follows.
<Development>
After the polyethylene terephthalate film is peeled off, a 1 mass% Na ₂ CO ₃ aqueous solution at 30 ° C. is sprayed for a predetermined time using an alkali developing machine (produced by Fuji Kiko Co., Ltd., a dry film developing machine), and an unexposed portion of the photosensitive resin layer Was dissolved and removed in a time twice the minimum image time. At this time, the minimum time required for completely dissolving the photosensitive resin layer in the unexposed portion was defined as the minimum development time.

<Plating>
Pretreatment: Immerse in an acidic degreasing agent FRX (10% aqueous solution, manufactured by Atotech Japan) at 40 ° C. for 4 minutes. Thereafter, it is washed with water, soaked in an APS aqueous solution (ammonium persulfate aqueous solution, concentration 200 g / L) for 1 minute at room temperature, washed with water, and soaked in a 10% sulfuric acid aqueous solution for 2 minutes.
Copper sulfate plating: Plating was performed at a current density of 5.0 A / dm ² for 30 minutes with the following plating solution composition.
<Composition of copper sulfate plating solution>
Pure water: 58. 9%
Copper sulfate conch (Meltex): 30%
Concentrated sulfuric acid: 10%
Concentrated hydrochloric acid: 0. 1%
Copper cream 125 (Meltex): 1%
<Resist stripping>
The cured resist was peeled off by spraying a 3% by mass aqueous sodium hydroxide solution heated to 50 ° C. onto the evaluation substrate after development.

2. Evaluation Method (1) Evaluation of Aggregability A photosensitive layer (resist layer) having a thickness of 40 μm and an area of 0.16 m ^{2 in} the photosensitive resin laminate is dissolved in 200 ml of a 1% by mass Na ₂ CO ₃ aqueous solution, and a circulation spray. Spraying was performed using an apparatus at a spray pressure of 0.1 MPa for 3 hours. Thereafter, the developer was allowed to stand for 1 day, and the generation of aggregates was observed. When a large amount of agglomerates are generated, powdery or oily substances are observed at the bottom and side surfaces of the spray device. In addition, aggregates may float in the developer. A composition having good developer cohesiveness does not generate these aggregates at all, or even if they are generated, they can be easily washed away with a small amount of water. The state of occurrence of aggregates was ranked by visual observation as follows.
A: No agglomerates are generated. O: There is no agglomerates at the bottom or side of the spray device, but a very small amount of agglomerates that can be visually confirmed are observed in the developer, but they are easily washed away when washed with water.
X: Aggregates are floating in the bottom or part of the side surface of the spray device and the developer. Even if it is washed with water, everything cannot be washed away.

(2) Resolution Evaluation The substrate for resolution evaluation that had passed 15 minutes after lamination was exposed with a line pattern in which the width of the exposed area and the unexposed area was 1: 1. Development was performed with a development time twice as long as the minimum development time, and the minimum mask width in which a cured resist line was normally formed was defined as a resolution value, and the resolution was ranked as follows.
A: Resolution value of 35 μm or less ○: Resolution value of more than 35 μm, 40 μm or less ×: Resolution value of more than 40 μm

(3) Plating resistance evaluation The substrate for resolution evaluation that had passed 15 minutes after lamination was exposed with a line pattern in which the width of the exposed area and the unexposed area was 1: 1. Development was performed with a development time twice as long as the minimum development time, and copper sulfate plating was performed according to the above plating conditions. The copper sulfate plating line of L / S = 30/30 μm after the cured resist was peeled was observed with an optical microscope and ranked as follows.
(Double-circle): There is no peeling of secondary copper plating, and the favorable plating line is formed.
○: The drilling width of the secondary copper plating is about 10 μm on one side of the line.
X: The drilling width of the secondary copper plating is 10 μm or more on one side of the line.

    According to the present invention, it is suitable as an etching resist or a plating resist in the fields of production of printed wiring boards, flexible wiring boards, lead frames, semiconductor packages and the like, and precision metal processing.

Claims (11)

(A) Alkali-soluble polymer having a carboxyl group content of 100 to 550 in terms of acid equivalent and a weight average molecular weight of 5,000 to 500,000: 20 to 90% by mass, (b) ethylenic addition polymerization monomer: 3 to 3 70% by mass, (c) 2,4,5-triarylimidazole dimer represented by the following general formula (I) or (II): 0.1 to 20% by mass, and (d) the following general A photosensitive resin composition comprising an allyl phosphate compound represented by formula (III): 1.0 to 15% by mass.

(In the formulas (I) and (II), A ₁ , A ₂ , and A ₃ each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms and an alkoxy group, or a halogen atom, and p, q and r are each independently an integer of 1 to 5.)

(In the formula, B ₁ represents any _one of a hydrogen atom, an alkyl group having 1 to 10 carbon atoms and an alkoxy group, or a halogen atom, and B ₂ represents any one of an alkyl group having 1 to 10 carbon atoms and an allyl group. And p is an integer of 1 to 3, and q is an integer of 1 to 5.) The content of the 2,4,5-triary-imidazole dimer represented by (c) the following general formula (I) or (II) is 2.0 to 20% by mass. Photosensitive resin composition. The photosensitive resin composition according to claim 1 or 2, further comprising (e) an alkylene oxide compound represented by the following general formula (IV): 1 to 30% by mass.

(In the formula, n is an integer of 4 to 100, R ₁ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and R ₂ and R ₃ are each independently a hydrogen atom, a methacrylic acid ester, or an acrylic acid ester. )   The photosensitive resin laminated body by which the photosensitive resin composition layer containing the photosensitive resin composition as described in any one of Claim 1 to 3 and the support body were laminated | stacked.   A method for forming a resist pattern, comprising: laminating the photosensitive resin laminate according to claim 4 on a substrate, exposing the laminate to ultraviolet light, and then removing an unexposed portion by development.   6. The resist pattern forming method according to claim 5, wherein in the exposure step, exposure is performed without using a photomask.   A method for producing a conductor pattern, comprising using a metal plate or a metal-coated insulating plate as a substrate, and etching or plating a substrate on which a resist pattern is formed by the method according to claim 5 or 6.   A method for producing a printed wiring board, comprising using a metal-coated insulating plate as a substrate, etching or plating a substrate on which a resist pattern is formed by the method according to claim 5 or 6, and peeling the resist pattern.   A method of manufacturing a lead frame, comprising: using a metal plate as a substrate; etching a substrate on which a resist pattern is formed by the method according to claim 5; and removing the resist pattern.   A method for manufacturing a semiconductor package, comprising: using a wafer on which circuit formation as an LSI has been completed as a substrate; plating a substrate on which a resist pattern is formed by the method according to claim 5; and removing the resist pattern. .   A method for producing a substrate having a concavo-convex pattern, comprising: using a glass rib as a substrate; processing the substrate on which a resist pattern is formed by the method according to claim 5 or 6 by a sandblasting method; and peeling the resist pattern.