JPH11149157A - Photoresist film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance sensitivity, resolution, adhesion, etching resistance, and resist patterning performance, and to prevent occurrence of cracking of a conductor and impregnation into it by specifying the thickness and the surface roughness of a support and incorporating a specified amount of a specified compound as the photopolymerization initiator of a photosensitive resin composition. SOLUTION: This photoresist film comprises the support film having a thickness of 10-30 μm and a surface roughness (Ra) of 1-15 nm and a photosensitive resin composition layer comprising a carboxyl-containing polymer and an ethylenically unsaturated compound and the photopolymerization initiator. A compound to contained in this layer in an amount of 0.1-10 weight% of the total weight of the carboxyl-containing polymer and the ethylenically unsaturated compound and it is used as the photopolymerization initiator represented by the formula in which each of R1 and R2 is, independently from each other, an H atom or an alkyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoresist film used for producing a printed wiring board, and more particularly to a photoresist film having excellent sensitivity, resolution, adhesion, and etching resistance, which is free from a conductor being applied or penetrated by etching. The present invention relates to a photoresist film having excellent resist pattern formability with no unevenness in the resist pattern.

[0002]

2. Description of the Related Art A photoresist method using a photosensitive resin composition is used for manufacturing a printed wiring board and the like. In this photoresist method, for example, a photosensitive material is first exposed on a support such as a transparent film. After applying the photosensitive resin composition to form a photosensitive resin composition layer, the photosensitive resin composition layer is laminated on the surface of a substrate on which a desired pattern is to be formed, and then the photosensitive resin composition layer is formed. After exposing the original image through a pattern mask, the unexposed portions are removed by a developing process using a solvent or an aqueous alkali solution to form a resist image, and the formed resist image is used as a protective mask,
After performing a well-known etching process or pattern plating process, the method of manufacturing a printed circuit board by peeling a resist is usually performed. In such a manufacturing process, it is required to have high sensitivity in order to improve productivity and shorten time. Furthermore, in recent years, printed wiring boards have been miniaturized and densified with the reduction in size and weight of electronic devices, and dry film resists (hereinafter, abbreviated as DFRs) having high resolution have been demanded.

As the photopolymerization initiator used in such a photosensitive resin composition, for example, conventional benzoins, ketones, quinones, diketones, alkyl oxime esters and the like, or a combination thereof, for example, JP 61
In JP-173242, benzophenone / Michler's ketone / N-phenylglycine, and in JP-A-6-69631, Michler's ketone or thioxanthone compound /
N-phenylglycine and the like are used. In JP-A-2-48664, 4,4 'is used as a photopolymerization initiator.
-A resin composition having high sensitivity and high resolution using bis (dialkylamino) benzophenone / aromatic ketone / rofin dimer has been proposed. Further, JP-A-2-6254
In JP-A-5, a combination system of a specific benzoin and a 2,4,5-triarylimidazole dimer is used, the curing speed is fast, the storage stability is good, the tenting property and the like. The resolution is improved.

[0004]

However, the photopolymerization initiator systems described in these publications are still unsatisfactory in sensitivity in view of recent advances in technology and high precision. When the concentration of the photopolymerization initiator is increased to increase the viscosity, the internal curability deteriorates, causing problems such as a reduction in resolution and developer resistance. Further, a combination system of 4,4'-bis (dialkylamino) benzophenone / aromatic ketone / rophin dimer described in JP-A-2-48664 and benzoins described in JP-A-2-62545 and 2,2 As a result of detailed studies by the present inventors, the use of a combination system of 4,5-triarylimidazole dimer alone is not satisfactory in terms of resolution, sensitivity and the like, and there is still room for improvement.

On the other hand, for the purpose of improving sensitivity, resolution, and adhesion, a photoresist film having a haze value of 0.
It has been proposed to use a support film of 1 to 1.5% (JP-A-6-230579, JP-A-8-1).
No. 23018), in this technique, when a normal alkali-developing dry film resist is used, the adhesion between the metal substrate and the resist is taken into consideration with the refinement and refinement accompanying the recent advancement of the technique. Then, it is still unsatisfactory, and there is a problem that the etching resistance is inferior, for example, the conductor is entangled or penetrated by etching, the yield is reduced, and the resist pattern is jagged. Under such circumstances, the present invention provides a photoresist film having excellent sensitivity, resolving power, and adhesion, excellent in etching resistance without skewing or penetration of a conductor in etching, and excellent in resist pattern formation. The purpose is to provide.

[0006]

Means for Solving the Problems However, the present inventors have conducted intensive studies to solve such problems, and as a result, the support film (I) / photosensitive resin composition layer (II) / protective film (III) In a photoresist film consisting of
The thickness of the support film (I) is 10 to 30 μm, the surface roughness (Ra) is 0.001 to 0.015 μm, and the photosensitive resin composition layer (II) is (a) a carboxyl group-containing polymer. (B) an ethylenically unsaturated compound, (c)
(C) as a photopolymerization initiator,
With respect to 100 parts by weight of the total weight of (a) and (b), (c-
1) N-aryl-α-amino acid-based compound in an amount of 0.01 to
1.0 part by weight, (c-2) N, N'-tetraalkyl-
4,4'-diaminobenzophenone-based compound
0.5 parts by weight, 0.5% by weight of (c-3) lophine dimer
The present inventors have found that a photoresist film containing 6.0 parts by weight and 0.1 to 10 parts by weight of a compound represented by the following formula (c-4) satisfies the above object, and completed the present invention. .

[0007]

Embedded image (Here, R ₁ and R ₂ are hydrogen or an alkyl group, which may be the same or different from each other.) In the present invention, particularly, the support film (I) is subjected to easy lubrication. It is preferable to use a support film (I) which has been applied and has a coefficient of static friction (μs) of 1.0 or less and a coefficient of dynamic friction (μd) of 0.8 or less between the slippery treated surfaces.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The support film (I) used in the present invention is, of course, transparent, the support film (I) has a thickness of 10 to 30 μm, preferably 12 to 25 μm, and a surface roughness (Ra) of 0. 0.001 to 0.015 μm, preferably 0.002 to 0.01 μm. If the thickness of the support film (I) is less than 10 μm, the film is too flexible, which makes handling inconvenient.
If the thickness exceeds μm, the resolution is reduced and the cost is increased. On the other hand, if the surface roughness (Ra) is less than 0.001 μm, the film surface is easily damaged during the film forming process,
If the thickness exceeds 0.015 μm, the resist pattern may be jagged, causing cracks or disconnection of the conductor.

Here, the surface roughness (Ra) is defined by the new JIS
It is measured based on B0601, and is determined by a surface roughness measuring device Surfcoder SE-30D (manufactured by Kosaka Laboratory Co., Ltd.).

[0010] In the present invention, the surface roughness (Ra) is 0.1.
Support film (I) in the range of 001 to 0.015 μm
The material is not particularly limited as long as it is a film obtained by subjecting a film of Toray T60 type, Teijin O type, M62 type, X71 type or the like to a slippery treatment. The lubricating treatment is performed by coating a polyester, acrylic, urethane, silicone, or fluorine resin on the film surface.

[0011] Further, the support film (I) which has been subjected to the slippery treatment may have a coefficient of static friction (μs) of 1.0 or less and a coefficient of dynamic friction (μd) of 0.8 or less between the slippery treated surfaces. It is particularly preferable, and remarkably exerts the effects of the present invention. The coefficient of static friction (μs) is 1.0 and the coefficient of dynamic friction (μ
If d) exceeds 0.8, the film surface is easily damaged during the film forming process, which is not preferable. Here, the static friction coefficient (μs) and the dynamic friction coefficient (μd) are based on JIS K7
125.

The photosensitive resin composition layer (II) of the present invention comprises:
The photosensitive resin composition contains (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, and (c) a photopolymerization initiator. As the (a) carboxyl group-containing polymer used in the present invention, an acrylic copolymer containing (meth) acrylic acid ester as a main component and copolymerized with an ethylenically unsaturated carboxylic acid is preferably used. If necessary, an acrylic copolymer obtained by copolymerizing another copolymerizable monomer can be used. In this case, the content of each component is 70-85% by weight of the (meth) acrylate component, preferably 75-82%.
% By weight, and 15 to 30 ethylenically unsaturated carboxylic acid components
% By weight, preferably from 18 to 25% by weight, and the other copolymerizable monomer component often from 0 to 15% by weight.

Here, the (meth) acrylate includes methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate,
-Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, and the like. You.

As the ethylenically unsaturated carboxylic acid, for example, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid are preferably used.
Dicarboxylic acids such as fumaric acid and itaconic acid, or anhydrides and half esters thereof can also be used. Of these, acrylic acid and methacrylic acid are particularly preferred.

Examples of other copolymerizable monomers include, for example, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acryl dimethylaminoethyl ester,
(Meth) acrylic acid diethylaminoethyl ester, methacrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, (meth) acrylamide, 2,2,3,3-tetrafluoropropyl (meth) acrylate acrylamide, Examples include diacetone acrylamide, styrene, α-methylstyrene, vinyl toluene, vinyl acetate, alkyl vinyl ether, (meth) acrylonitrile and the like.

The carboxyl group-containing polymer (a) thus obtained may be used in combination with a polyester resin, a polyamide resin, a polyurethane resin, an epoxy resin, and the like. The carboxyl group-containing polymer has a weight average molecular weight of 10,000 to 300,000, preferably 10,000 to 150,000, more preferably 300 to 300,000.
When the molecular weight is small, cold flow is liable to occur. Conversely, when the molecular weight is large, development is difficult, and the resolution is lowered, and the peelability at the time of peeling the resist is poor.

(B) As the ethylenically unsaturated compound,
Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, butylene Glycol di (meta)
Acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexane glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol Di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 2,2-bis (4-acryloxy) Diethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3- (meth) acryloyloxypropyl acryle DOO, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate,
1,6-hexamethyldiglycidyl ether di (meth)
Acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate, bisphenol A
Examples include polyfunctional monomers such as diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate, and glycerin polyglycidyl ether poly (meth) acrylate.

An appropriate amount of a monofunctional monomer can be used together with these polyfunctional monomers. Examples of such a monofunctional monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2
-Phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropylphthalate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) ) Acryloyloxyethyl acid phosphate, phthalic acid derivative half (meth) acrylate, N-methylol (meth) acrylamide, and the like.

The mixing ratio of (b) the ethylenically unsaturated compound is as follows: (a) a carboxyl group-containing polymer and (b)
5-90% by weight, preferably 20-80% by weight, particularly preferably 40% by weight, based on the total weight of the ethylenically unsaturated compound.
It is desirable to select from the range of ６０60% by weight. (B) An insufficient amount of the ethylenically unsaturated compound causes poor curing, reduced plasticity, and a delay in the development speed. (B) An excessive amount of the ethylenically unsaturated compound causes an increase in tackiness, cold flow, and peeling of the cured resist. It is not preferable because the speed decreases.

(C) As the photopolymerization initiator, (c-1)
N-aryl-α-amino acid compounds, (c-2) N,
N'-tetraalkyl-4,4'-diaminobenzophenone-based compound, (c-3) lophin-based dimer, (c-
4) At least a compound represented by the above formula is contained. (C-1) Examples of N-aryl-α-amino acid compounds include N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-phenylglycine, and N-phenylglycine.
(N-propyl) -N-phenylglycine, N- (n-
Butyl) -N-phenylglycine, N- (2-methoxyethyl) -N-phenylglycine, N-methyl-N-phenylalanine, N-ethyl-N-phenylalanine,
N- (n-propyl) -N-phenylalanine, N-
(N-butyl) -N-phenylalanine, N-methyl-
N-phenylvaline, N-methyl-N-phenylleucine, N-ethyl-N- (p-tolyl) glycine, N-
(N-propyl) -N- (p-tolyl) glycine, N-
(N-butyl) -N- (p-tolyl) glycine, N-methyl-N- (p-chlorophenyl) glycine, N-ethyl-N- (p-chlorophenyl) glycine, N- (n-
Propyl) -N- (p-chlorophenyl) glycine, N
-Methyl-N- (p-bromophenyl) glycine, N-
Ethyl-N- (p-bromophenyl) glycine, N-
(N-butyl) -N- (p-bromophenyl) glycine, N, N'-diphenylglycine, N-methyl-N-
(P-iodophenyl) glycine, N- (p-bromophenyl) glycine, N- (p-chlorophenyl) glycine, N- (o-chlorophenyl) glycine, etc., and N-phenylglycine is preferably used. .

(C-2) N, N'-tetraalkyl-
As 4,4'-diaminobenzophenone-based compounds,
N, N'-tetramethyl-4,4'-diaminobenzophenone, N, N'-tetraethyl-4,4'-diaminobenzophenone, N, N'-tetrapropyl-4,4 '
-Diaminobenzophenone, N, N'-tetrabutyl-
4,4'-diaminobenzophenone and the like are preferable, and N, N'-tetraethyl-4,4'-diaminobenzophenone and N, N'-tetramethyl-4,4'-diaminobenzophenone are preferably used.

(C-3) Examples of the lophine dimer include triphenyl biimidals, particularly 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) 4,5-diphenylimidazole Dimer, 2,4- (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (o-ethoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p- Ethoxyphenyl) -5-phenylimidazole dimer and the like.
(O-Chlorophenyl) -4,5-diphenylimidazole dimer is used. (C-4) Examples of the compound represented by the above formula include benzyl dimethyl ketal, benzyl diethyl ketal, and the like, preferably benzyl dimethyl ketal.

The amount of the photopolymerization initiator (c) is as follows:
0.01 to 100 parts by weight of the total weight of (a) and (b)
To 20 parts by weight, preferably 0.1 to 15 parts by weight,
For each photopolymerization initiator, the compounding amount of (c-1) is 0.01 to 1.0 part by weight, preferably 0.01 part by weight, based on 100 parts by weight of the total weight of (a) and (b). ~ 0.5
Parts by weight, and the compounding amount of (c-2) is 0.01 to 0.1.
5 parts by weight, preferably 0.01 to 0.3 parts by weight,
The compounding amount of (c-3) is 0.5 to 6.0 parts by weight, preferably 0.5 to 3.0 parts by weight, and the compounding amount of (c-4) is 0.1 to 10 parts by weight. Parts, preferably 1.0 to 5.0 parts by weight.

If the amount of component (c) is less than 0.01 part by weight, curing will be poor, and if it exceeds 20 parts by weight, the adhesion will decrease. Also, (c-
If the amount of 1) is less than 0.01 part by weight, the sensitivity decreases,
If it exceeds 1.0 part by weight, the adhesive strength is undesirably reduced. If the amount of (c-2) is less than 0.01 part by weight, the resolving power will decrease, and if it exceeds 0.5 part by weight, the adhesion will decrease, which is not preferable. The compounding amount of (c-3) is 0.5
If the amount is less than 10 parts by weight, the effect of the present invention cannot be obtained. If the amount is more than 6.0 parts by weight, the adhesive strength and storage stability decrease, which is not preferable. If the amount of (c-4) is less than 0.1 part by weight, the effects of the present invention cannot be obtained. If the amount exceeds 10 parts by weight, the adhesion and the resolving power are undesirably reduced.

In the present invention, it is also preferable to use other initiators in addition to (c-1) to (c-4) as the photopolymerization initiator (c). Other initiators include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether,
Benzoin n-butyl ether, benzoin phenyl ether, benzyl diphenyl disulfide, dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,
3'-dimethyl-4-methoxybenzophenone, benzophenone, p, p'-bis (dimethylamino) benzophenone, p, p'-bis (diethylamino) benzophenone, pivaloin ethyl ether, 1,1-dichloroacetophenone, p- t-butyldichloroacetophenone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-diethylthioxanthone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-dichloro-4- Phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibezosparone, 1-
(4-Isopropylphenyl) -2-hydroxy-2-
Examples thereof include methyl-1-propanone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, tribromophenylsulfone, tribromomethylphenylsulfone, and the like. These may be used alone or in combination of two or more. Are used in combination.

Thus, the photosensitive resin composition (II) used in the photoresist film of the present invention is obtained from (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, and (c) a photopolymerization initiator. However, if necessary, other additives include a thermal polymerization inhibitor, a plasticizer, a dye (colorant, a discoloring agent), an adhesion promoter, an antioxidant, a solvent, a surface tension modifier, a stabilizer, and a chain transfer. Agents, defoamers, flame retardants,
And the like can be appropriately added.

For example, a thermal polymerization inhibitor is added for preventing thermal polymerization or polymerization with time of the photosensitive resin composition, and includes p-methoxyphenol, hydroquinone, t
-Butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine, chloranil, naphthylamine, β-naphthol, 2,6-di-t-butyl-p-cresol, nitrobenzene , Picric acid, p
-Toluidine and the like.

The plasticizer is added to control the physical properties of the film. Examples of the plasticizer include phthalic acid esters such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate and diallyl phthalate; triethylene glycol diacetate, tetraethylene glycol diacetate and the like. Glycol esters; phosphate esters such as tricresyl phosphate and triphenyl phosphate;
Amides such as p-toluenesulfonamide, benzenesulfonamide, Nn-butylacetamide; aliphatic dibasic acid esters such as diisobutyl adipate, dioctyl adipate, dimethyl sebacate, dioctyl azelate, dibutyl malate; citric acid Triethyl, tributyl citrate, glycerin triacetyl ester,
Glycols such as butyl laurate, dioctyl 4,5-diepoxycyclohexane-1,2-dicarboxylate, polyethylene glycol and polypropylene glycol are exemplified.

Examples of the dye include tris (4-dimethylaminophenyl) methane [leucocrystal violet], tris (4-diethylamino-2-methylphenyl) methane, leucomalachite green, leucoaniline, leucomethyl violet, brilliant green, Eosin, ethyl violet, erythrosin B,
Methyl green, crystal violet, basic fuchsin, phenolphthalein, 1,3-diphenyltriazine, alizarin red S, thymolphthalein, methyl violet 2B, quinaldine red, rose bengal, methanil yellow, thymol sulfophthalein, xylenol blue , Methyl orange, orange
IV, diphenylthiocarbazone, 2,7-dichlorofluorescein, paramethyl red, congo red, benzopurpurine 4B, α-naphthyl red, nile blue A, phenacetaline, methyl violet, malachite green, parafuchsin, rhodamine 6G, oil blue # 603, Victoria Pure Blue BOH, Spiron Blue GN and the like. Above all, it is preferable to contain 0.01 to 0.5% by weight, preferably 0.01 to 0.2% by weight of a leuco dye such as leuco crystal violet, malachite green and brilliant green.

The discoloring agent is added to the photosensitive resin composition so that a visible image can be given by exposure, and specific examples thereof include diphenylamine, dibenzylaniline, triphenylamine, diethylaniline, Diphenyl-p-phenylenediamine, p-toluidine,
4,4'-biphenyldiamine, o-chloroaniline,
And the like.

Examples of the adhesion promoter include benzimidazole, benzthiazole, benzoxozole, benztriazole, 2-mercaptobenzthiazole,
-Mercaptobenzimidazole and the like. In addition, it is also preferable to use an organic halogen compound in combination with the above-mentioned dyes, such as amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzyl bromide, methylene bromide, and tribromomethylphenylsulfone. , Carbon tetrabromide, tris (2,3-dibromopropyl)
Phosphate, trischloroacetamide, amyl iodide, isobutyl iodide, 1,1,1-trichloro-2,
2-bis (p-chlorophenyl) ethane hexachloroethane and the like.

The protective film (III) used in the present invention
When the photoresist film is used in the form of a roll, it prevents the photosensitive resin composition layer having adhesiveness from being transferred to the support film or preventing the photosensitive resin composition layer from adhering walls and the like. It is used by laminating on the photosensitive resin composition layer for the purpose. Examples of such a protective film include a polyester film, a polyethylene film, a polypropylene film, a polyvinyl alcohol film, a Teflon film, and the like, but the present invention is not limited to only such examples. The thickness of the protective film is not particularly limited, and is usually 10 to 50 μm,
Above all, it may be 10 to 30 μm.

Thus, in the present invention, the support film (I), the photosensitive resin composition layer (II), the protective film (II)
A photoresist film is obtained by sequentially laminating I). Next, the production of the photoresist film of the present invention and the method of producing a printed wiring board using the same will be described. (Lamination method) A support film (I) such as a polyester film, a polypropylene film, a polystyrene film, and a vinylon film is prepared by using the above photosensitive resin composition (II).
After coating on the surface, a protective film (III) such as a polyethylene film is coated from above the coated surface to form a photoresist film.

(Exposure) In order to form an image with a photoresist film, the protective film (III) is peeled off and the photosensitive resin composition layer (II) side is adhered to a metal surface such as a copper surface of a copper clad substrate. After the attachment, a pattern mask is brought into close contact with the other support film (I) and exposed. Exposure is usually performed by ultraviolet irradiation, and as a light source at that time,
A high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a xenon lamp, a metal halide lamp, a chemical lamp and the like are used. After UV irradiation, heat if necessary,
Complete curing can be achieved.

(Development) After exposure, the film on the resist is peeled off and developed. Since the photosensitive resin composition of the present invention is a rare alkali developing type, development after exposure is
This is performed using a dilute aqueous solution of about 0.3 to 2% by weight of alkali such as sodium carbonate and potassium carbonate. A surfactant, an antifoaming agent, a small amount of an organic solvent for accelerating development, and the like may be mixed in the alkaline aqueous solution.

(Etching, Plating) The etching is usually carried out using an acidic etching solution such as an aqueous solution of cupric chloride-hydrochloric acid or an aqueous solution of ferric chloride-hydrochloric acid according to a conventional method. Rarely, an ammonia-based alkali etching solution is also used. In the plating method, after performing pretreatment using a plating pretreatment agent such as a degreasing agent and a soft etching agent, plating is performed using a plating solution.

(Removal of Hardened Resist) After the etching step, the remaining hardened resist is removed. Stripping and removal of the cured resist is performed using an alkali stripping solution composed of an aqueous alkali solution having a concentration of about 0.5 to 5% by weight such as sodium hydroxide or potassium hydroxide.

The photoresist film of the present invention is very useful as an etching resist or a plating resist used in the production of printed wiring boards, precision metal processing, lead frame production, and the like.
Support film having specific surface roughness (Ra) (I)
/ (A) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, (c) a photopolymerization initiator,
1) Since the photosensitive resin composition layer (II) / protective film (III) contains specific amounts of (c-2), (c-3) and (c-4), sensitivity, resolution, It exhibits excellent effects on adhesion, etching resistance, and resist pattern formation.

[0039]

The present invention will be described in more detail with reference to the following examples. Unless otherwise specified, “%” and “parts” are based on weight. [Preparation of photosensitive resin composition] As (a), the following carboxyl group-containing polymer was used, and (b), (c-1),
(C-2), (c-3), (c-4) and other additives are doped with the photosensitive resin compositions (II-1) to (II-12) having the compositions shown in Table 1. Was prepared. (A) methyl methacrylate / butyl acrylate /
40% methyl ethyl ketone / isopropyl alcohol (weight ratio 50/50) solution of a copolymer having a composition of 2-ethylhexyl acrylate / methacrylic acid (weight ratio: 48/10/20/22) and a weight average molecular weight of 70,000

[0040]

[Table 1] Photosensitive tree (a) (b) (c-1) (c-2) (c-3) (c-4) Other fat composition Solid content TMPT-TA HOA-MPE NPG EAB-F HABI BDK LCV MG TBMPS (II) (%) (%) (%) (%) (%) (%) (%) (%) (%) (%) II-1 54.42 31.28 5.00 0.20 0.10 4.00 4.00 0.60 0.10 0.30 II-2 55.26 18.42 18.42 0.10 0.10 4.00 3.00 0.60 0.10 --- II-3 55.20 18.40 18.40 0.10 0.20 4.00 3.00 0.60 0.10 --- II-4 55.26 18.42 18.42 0.10 0.10 3.00 4.00 0.60 0.10 --- II-5 54.54 31.36 5.00 --- 0.10 4.00 4.00 0.60 0.10 0.30 II-6 53.82 30.88 5.00 1.20 0.10 4.00 4.00 0.60 0.10 0.30 II-7 54.24 31.16 5.00 0.10 --- 4.00 4.00 0.60 0.10 0.80 II-8 53.76 30.84 5.00 0.10 0.80 4.00 4.00 0.60 0.10 0.80 II-9 55.92 18.64 18.64 0.20 0.10 --- 5.00 0.60 0.10 0.80 II-10 51.72 17.24 17.24 0.20 0.10 7.00 5.00 0.60 0.10 0.80 II-11 56.52 32.68 5.00 0.20 0.10 4.00 --- 0.60 0.10 0.80 II-12 49.32 27.88 5.00 0.20 0.10 4.00 12.00 0.60 0.10 0.80

Note) TMPT-TA: Trimethylolpropane triacrylate (manufactured by Nippon Kayaku Co., Ltd.) HOA-MPE: 2-acryloyloxyethyl-2-hydroxyethylphthalic acid (manufactured by Kyoeisha Yushi Co., Ltd.) NPG: N-phenylglycine ( EAB-F: N, N'-tetraethyl-4,4'-diaminobenzophenone (Hodogaya) HABI: 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer (Hodogaya) BDK: Benzyl dimethyl ketal (I-651: Ciba Geigy) LCV: Leuco crystal violet (Hodogaya) MG: Malachite green (Hodogaya) TBMPS: Tribromomethylphenyl sulfone (Tokyo Kasei) (II) -5) to (II-12) are not the photosensitive resin compositions defined in the present invention.

Example 1 The photosensitive resin composition (II-1) was doped with a gap of 5
Using a mill applicator, a surface roughness (Ra) of 0.
Support film (I) consisting of a 002 μm polyester film (polyethylene terephthalate film)
(Thickness 16 μm), left at room temperature for 1 minute and 30 seconds, dried in an oven at 60 ° C., 90 ° C. and 110 ° C. for 3 minutes each to obtain a dry film having a resist thickness of 25 μm. A protective film (III) (thickness: 23 μm) was laminated to form a photoresist film. The support film (I) is subjected to a slipping treatment using a polyester resin, and the coefficient of static friction (μs) between the slipping treated surfaces is 0.8, and the coefficient of dynamic friction (μd).
Was 0.6.

The above photoresist film was placed on a copper-clad substrate preheated to 60 ° C. in an oven on a protective film (II).
While peeling off I), laminating roll temperature 100 ° C,
Roll pressure 3 kg / cm ² , lamination speed 1.5 m /
min. The copper-clad board used here was 1.6 mm in thickness, and was a board with a width of 200 mm and a length of 250 mm in which a 35 μm copper foil was attached to both sides of a glass fiber epoxy base material.

Next, the surface of the polyester film (I) of the obtained substrate was exposed with a 5 kW high-pressure mercury lamp (parallel light). At this time, a negative film (a 21-step stofer step tablet) made so that the light transmission amount was reduced stepwise so that the light sensitivity could be evaluated was used. After 15 minutes from the exposure, the polyester film (I) was peeled off, and a 1% aqueous solution of sodium carbonate was sprayed at 30 ° C. for a developing time twice as long as a break point (time for completely dissolving unexposed portions). The exposed portion was dissolved and removed to obtain a cured resin image. The substrate was etched with a cupric chloride etchant. At this time, the minimum required etching time was 60 seconds and the etching time was 90 seconds. Then 5
The cured resin film used as the resist was peeled off by spraying with a 3% aqueous sodium hydroxide solution at 0 ° C. for 120 seconds to form a relief image.

In the above, the following items were evaluated as follows. (Sensitivity) The photosensitivity of the photosensitive resin composition was evaluated by measuring the exposure amount when the number of steps of the step tablet of the photocurable film formed on the base material was six.

(Resolution) line / space = 1/1 (1
0, 15, 20, 25, 30, 35, 40, 45, 50
After exposure using a pattern mask (glass chrome dry plate) of (μm), development was performed for a time twice as long as the break point, and the evaluation was made based on the minimum line width (μm) at which an image was formed.

(Adhesion) After lamination on the substrate, the line width was 10, 15, 20, 25, 30, 35, 40, 45,
Using a 50 μm pattern mask (glass chrome dry plate: independent fine line), development was performed in the same manner, and the minimum line width (μm) with good adhesion was examined.

(Etching resistance) (A) Penetration into conductor After development of line / space = 400 μm / 300 μm,
After the resist pattern was etched and the resist was peeled off, the substrate was observed with a magnifying microscope and the degree of penetration of the etching solution was visually evaluated. The evaluation criteria are as follows. ◎ ・ ・ ・ No permeation ○ ・ ・ ・ Permeate less than 2μm △ ・ ・ ・ Permeate less than 2-5μm × ・ ・ ・ Permeate more than 5μm

(B) Covering of conductor After development of line / space = 400 μm / 300 μm,
After the resist pattern was etched and the resist was peeled off, the base material was observed with a magnifying microscope, and the degree of chipping of the conductor was visually evaluated. The evaluation criteria are as follows.・ ・ ・: No chipping of conductor ○: Chipping less than 1/3 from end of conductor width △: Chipping of 1/3 or more from end of conductor width × ..No conductor

(Rewinding property) While slitting the photoresist film to a width of 300 mm, a length of 150 m was wound on an ABS resin pipe having an inner diameter of 76.2 mm, and both ends of the pipe were fixed. 3 under RH conditions
Stored suspended in the air for days. After storage, the temperature was returned to room temperature (23 ° C.), and the coil was left standing for one week, and the winding deviation was measured. The evaluation criteria are as follows. ○ ・ ・ ・ No deviation △ ・ ・ ・ There is deviation less than 1mm × ・ ・ ・ There is deviation more than 1mm

Examples 2 to 4 and Comparative Examples 1 to 11 The same procedures as in Example 1 were carried out except that the photosensitive resin composition (II) and the support film (I) as shown in Table 2 were used. Was evaluated. Table 3 shows the evaluation results of the examples and the comparative examples.

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Table 2 Photosensitive resin support film (I) composition (II) Thickness Surface roughness Static friction coefficient Dynamic friction coefficient (μm) (μm) Example 1 II-1 16 0.002 0.8 0.6 〃2 II-2 16 0.002 0.8 0.6 ３ 3 II-3 15 0.005 1.0 0.7 〃 4 II-4 20 0.010 0.8 0.6 Comparative Example 1 II-5 20 0.010 0.8 0.6 〃 2 II-6 20 0.010 0.8 0.6 ３ 3 II-7 20 0.010 0.8 0.6 〃 4 II-8 20 0.0100. 8 0.6 〃 5 II-9 20 0.010 0.8 0.6 〃 6 II-10 20 0.010 0.8 0.6 〃 7 II-11 20 0.010 0.8 0.6 〃 8 II-12 20 0.010 0.8 0.6 ９ 9 II-1 20 0.025 0.6 0.4 〃 10 II-1 38 0.010 2.0 1.0 〃 11 II-2 20 0.030 0.5 0.3

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[Table 3] Sensitivity resolution Adhesion resistance Etching resistance Winding property (mj / cm ² ) Line width Line width (a) (b) (μm) (μm) Example 1 25 25 30 ◎ ◎ ○ ○ 〃 230 25 35 ◎ ◎ ○ 〃 330 30 30 ◎ ◎ ○ 〃 430 30 35 ◎ ◎ ○ Comparative Example 1 60 30 35 ○ ○ 〃 215 50 60 × ○ 〃 340 50 30 ○ ○ ２０ ４ 420 380 × △ ○ 〃 580 4050 △ △ ○ ６ 625 4550 ○ △ ○ 〃 760 35 35 △ △ ○ 〃 825 4550 × △ ○ ９ 930 30 30 ○ ○ ○ 〃 10 30 35 30 ○ ○ × 〃 11 40 30 35 ○ × ○

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The photoresist film obtained according to the present invention has good sensitivity, resolution, adhesion to metal substrates, excellent etching resistance, and excellent resist pattern forming properties, so that printed wiring It is useful as an etching resist or a plating resist used in the manufacture of a plate, the manufacture of a lead frame, the precision processing of metal, and the like.

Claims (6)

[Claims] 1. A photoresist film comprising a support film (I) / photosensitive resin composition layer (II) / protective film (III), wherein the thickness of the support film (I) is 10 to 30 μm and the surface roughness is The degree (Ra) is 0.001 to
0.015 μm and the photosensitive resin composition layer (I
I) comprises (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, and (c) a photopolymerization initiator,
(C) As a photopolymerization initiator, the total weight of (a) and (b) is 1
(C-1) 0.01 to 1.0 part by weight of (c-1) N-aryl-α-amino acid compound based on 00 parts by weight;
0.01 to 0.5 parts by weight of an N, N'-tetraalkyl-4,4'-diaminobenzophenone compound, (c-
3) 0.5 to 6.0 parts by weight of a loffin dimer, (c-
4) A photoresist film comprising 0.1 to 10 parts by weight of a compound represented by the following formula. Embedded image (Here, R ₁ and R ₂ are hydrogen or an alkyl group, which may be the same or different from each other.) 2. The support film (I) has been subjected to a slippery treatment, and a coefficient of static friction (μ) between the slippery treated surfaces.
2. The photoresist film according to claim 1, wherein a support film (I) having a s) of 1.0 or less and a dynamic friction coefficient (μd) of 0.8 or less is used. 3. A photo-sensitive resin according to claim 1, wherein (c-1) a photosensitive resin composition (II) containing N-phenylglycine is used as the N-aryl-α-amino acid compound. Resist film. (C-2) N, N'-tetraalkyl-
As a 4,4'-diaminobenzophenone-based compound,
N, N'-tetraethyl-4,4'-diaminobenzophenone and / or N, N'-tetramethyl-4,4'-
Photosensitive resin composition containing diaminobenzophenone (II)
The photoresist film according to claim 1, wherein the photoresist film is used. 5. A photosensitive resin composition (I) containing triphenylbiimidazoles as a (c-3) lophine dimer.
The photoresist film according to claim 1, wherein I) is used. 6. The photoresist film according to claim 1, wherein (c-4) a photosensitive resin composition (II) containing benzyldimethyl ketal is used as the compound represented by the above formula. .