JPH11327132A - Photoresist film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject film excellent in the formation of pattern corresponding to a highly fine characteristic and a highly accurate characteristic by using as a protection film a film whose surface brought into contact with a photosensitive resin compound layer has a maximum roughness of not more than a specified value. SOLUTION: This film is composed of a support film, a photosensitive resin compound layer and a protection film. As the protection film, a film is used that has a surface brought into contact with the photosensitive resin compound layer has a maximum roughness of not more than 2.0 μm. As such the film, a biaxial stretched polypropylene film or polyethylene telephtalate film is used preferably. The thickness of the protection film may be 10-30 μm, and the protection film may be properly separatedly treated if necessary. As the photosensitive resin compound, well known one can be used, and it is normally composed of base polymer, ethylene unsaturated compound and a photopolymerization starter.

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 manufacturing a printed wiring board and a lead frame, and more particularly to a photoresist film excellent in formability of a conductor pattern formed without jaggedness. It is.

[0002]

2. Description of the Related Art In recent years, a photoresist method using a photosensitive resin has been used for manufacturing a printed wiring board and the like. Most of the photoresist film composed of the support film / photosensitive resin composition layer / protective film used in the photoresist method is of an alkali developing type. After exposure, the unexposed portion is developed with an alkali solution such as sodium carbonate. By doing so, the carboxylic acid group in the photosensitive resin composition becomes a carboxylate and becomes water-soluble, the unexposed portion is removed, and a resist image is formed. Using the resist image thus formed as a protective mask, a known etching process or pattern plating process is performed, and then the resist is peeled off to manufacture a printed circuit board. In the manufacture of such printed wiring boards and the like, a polyethylene film has conventionally been used as a protective film for the photoresist film.

[0003]

However, in the case of a photoresist film using the polyethylene film as a protective film, when the photosensitive resin composition layer surface is laminated on the substrate after the protective film is peeled off, the substrate and the photosensitive resin A large number of voids are generated between the composition layers, and it has been found that it is difficult to form a good pattern with recent miniaturization of a resist pattern. On the other hand, there is a countermeasure by softening the photosensitive resin composition, but this leads to a decrease in storage stability due to cold flow, and there is still room for improvement.

In view of the above, an object of the present invention is to provide a photoresist film having excellent pattern formability corresponding to high definition and high definition.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, it has been found that a protective film formed of a support film, a photosensitive resin composition layer, and a protective film is protected. As the film, the maximum roughness of the surface in contact with the photosensitive resin composition layer (R
It has been found that a photoresist film using a film having y) of 2.0 μm or less meets the above-mentioned object, and the present invention has been completed.

In the present invention, particularly, as the photosensitive resin composition layer, a base polymer (A) having an acid value of 100 to 200 mg KOH / g and a weight average molecular weight of 30,000 to 120,000, an ethylenically unsaturated compound (B), It comprises P, P'-bis (dialkylamino) benzophenone (C), hexaarylbiimidazole (D) and leuco dye (E), and (C) is added to 100 parts by weight of (A) and (B) in total. ) Is 0.01 to 0.25 parts by weight, and (D) is 1.0
When the photosensitive resin composition (a) containing 10 to 10 parts by weight and 0.05 to 2 parts by weight of (E) is used, the effect of the present invention is remarkably exhibited.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The support film used in the present invention is not particularly limited, and examples thereof include a polyester film, a polyvinyl alcohol film, a polyolefin film, and a nylon film. Among them, a polyester film (polyethylene terephthalate film) and a polyvinyl alcohol film are preferably used. . Further, as the support film, the haze value of the film is 0.01 to
A film having a range of 4.0%, preferably 0.01 to 2.0%, and more preferably 0.01 to 0.5% is particularly preferable in terms of sensitivity, resolution, adhesion and the like. It is difficult to obtain a film having a haze value of less than 0.01%,
If it exceeds 4.0%, sensitivity, resolution, and adhesion are poor, which is not preferable. Specifically, polyethylene terephthalate films such as Teijin's highly transparent film GS series, Diafoil Hoechst's R series, Dupont's Mylar D series, Toray's T series, Nippon Synthetic Chemical Industry's vinylon film, etc. No.

The haze value is a value representing turbidity, and is a total transmittance T of light radiated by a lamp and transmitted through a sample.
The haze value (H) (%) is obtained as H (%) = (D / T) × 100 from the following equation, and the transmittance D of the light diffused and scattered in the sample. These are specified by JISK 7105 and are commercially available turbidimeters, for example, Nippon Denshoku Industries N
It can be easily measured by DH-300A.

The thickness of the support film is 10 to 30 μm.
m, preferably 12 to 25 μm, more preferably 16 to
When the thickness is more than 30 μm, the resolution is lowered or the cost is increased. When the thickness is less than 10 μm, the film is too flexible, which is not convenient for handling.

The photosensitive resin composition used in the photosensitive resin composition layer of the present invention is not particularly limited, and known ones can be used. Usually, a base polymer, an ethylenically unsaturated compound and a photopolymerizable compound are used. A photosensitive resin composition comprising an initiator can be used. In the case of an alkali development type, a base polymer obtained by copolymerizing (meth) acrylic acid may be used. As the base polymer, an acrylic copolymer containing (meth) acrylic acid ester as a main component and copolymerized with an ethylenically unsaturated carboxylic acid is preferably used, and other copolymers can be used if necessary. It is also possible to use an acrylic copolymer obtained by copolymerizing various monomers. 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) acrylic acid ester 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 (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. In addition to the above, a polyester resin, a polyamide resin, a polyurethane resin, an epoxy resin, or the like can be used in combination with the base polymer thus obtained.

Examples of the ethylenically unsaturated compound include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and propylene glycol di (meth) acrylate. , Polypropylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, ethylene oxide modified bisphenol A type di (meth) acrylate, propylene oxide modified bisphenol A type di (meth) acrylate, 1,6-hexane glycol di (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, Lenglycol diglycidyl ether di (meth) acrylate, diethylene glycol diglycidyl ether di (meth) acrylate, diglycidyl phthalate di (meth) acrylate, hydroxypivalic acid-modified neopentyl glycol di (meth) acrylate, trimethylolpropane di ( Meta)
Acrylate, 1,6-hexamethyldiglycidyl ether di (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta ( (Meth) acrylate, glycerin polyglycidyl ether poly (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 2,2-bis (4-acryloxydiethoxyphenyl) propane,
Polyfunctional monomers such as 2,2-bis (4- (meth) acryloxypolyethoxyphenyl) propane, 2-hydroxy-3- (meth) acryloyloxypropyl acrylate, and trimethylolpropane triglycidyl ether tri (meth) acrylate Is mentioned.

An appropriate amount of a monofunctional monomer may be used in combination 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, half (meth) acrylate of a phthalic acid derivative, N-methylol (meth) acrylamide, and the like.

Examples of the photopolymerization initiator include N, N'-tetraalkyl-4,4'-diaminobenzophenone (Michler's ketone), benzoin, benzoin methyl ether,
Benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzoin isobutyl ether, benzyl diphenyl disulfide, benzyl dimethyl ketal, 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, pt-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-methyl-1-propanone, 2-methyl- [4
-(Methylthio) phenyl] -2-morpholino-1-
Propanone, tribromophenylsulfone, tribromomethylphenylsulfone, N-phenylglycine, 2,
4,6- [tris (trichloromethyl)]-1,3,5
-Triazine, 2,4- [bis (trichloromethyl)]-
6- (4'-methoxyphenyl) -1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6-
(4′-methoxynaphthyl) -1,3,5-triazine, 2,4- [bis (trichloromethyl)]-6- (piperonyl) -1,3,5-triazine, 2,4- [bis (trichloro Methyl)]-6- (4'-Methoxystyryl) -1,3,5-triazine and the like, and acridine derivatives such as acridine and 9-phenylacridine, and 2,2'-bis (o-chlorophenyl)- 4,
5,4 ′, 5′-tetraphenyl-1,2′-biimidazole, 2,2′-bis (o-chlorophenyl) -4,
5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-fluorophenyl)-
4,5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-methoxyphenyl)
-4,5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (p-methoxyphenyl) -4,5,4', 5'-tetraphenyl-1, 1 '
-Biimidazole, 2,4,2 ', 4'-bis [bi (p
-Methoxyphenyl)]-5,5'-diphenyl-1,
1'-biimidazole, 2,2'-bis (2,4-dimethoxyphenyl) -4,5,4 ', 5'-diphenyl-
1,1′-biimidazole, 2,2′-bis (p-methylthiophenyl) -4,5,4 ′, 5′-diphenyl-
Hexaarylbiimidazoles such as 1,1′-biimidazole and bis (2,4,5-triphenyl) -1,1′-biimidazole, etc., and these can be used alone or in combination of two or more. .

In the present invention, particularly, among the above photosensitive resin compositions, a base polymer (A) having an acid value of 100 to 200 mg KOH / g and a weight average molecular weight of 30,000 to 120,000, and an ethylenically unsaturated compound (B) , P, P '
-Bis (dialkylamino) benzophenone (C), hexaarylbiimidazole (D) and leuco dye (E), wherein (C) is added in an amount of 0.1% to 100 parts by weight in total of (A) and (B). 01 to 0.25 parts by weight, (D)
Is preferably used, and the photosensitive resin composition (a) containing 0.05 to 2 parts by weight of (E) is used, and the effect of the present invention is remarkably exhibited.

Hereinafter, the photosensitive resin composition (a) will be specifically described. As the base polymer (A), a carboxyl group-containing acrylic resin is usually used and can be obtained in the same manner as described above. The acid value of the pace polymer (A) is 100 to 200 mgKOH / g, preferably 120 to 200 mgKOH / g.
~ 180mgKOH / g, more preferably 130 ~ 17
At 0 mgKOH / g, if the acid value is less than 100 mgKOH / g, good developability cannot be obtained and the desired resolution cannot be obtained. Conversely, if the acid value exceeds 200 mgKOH / g, the developing speed becomes too fast at a film thickness of 25 μm or less, and the control becomes too high. It becomes difficult, and furthermore, the formed pattern may be attacked by the developer. The acid value can be satisfied by, for example, copolymerizing the ethylenically unsaturated carboxylic acid in the base polymer (A) at about 15 to 30% by weight.

Further, the weight average molecular weight of the base polymer (A) is from 30,000 to 120,000, preferably from 50,000.
000 to 100,000, particularly preferably 60,000 to 9
If the weight average molecular weight is less than 3,000 at 0000, the resin becomes too soft, and when processed into a roll form, edge fusion of the resin seeping out occurs.
If it exceeds 00, the resolution is undesirably reduced.

As the ethylenically unsaturated compound (B),
The above ethylenically unsaturated compound is used, and two or more bifunctional monomers may be used, or a monofunctional monomer or a trifunctional or higher functional monomer may be used in combination with a bifunctional monomer in an appropriate amount. As the photosensitive resin composition (a), as the bifunctional monomer having two polymerizable unsaturated groups, tetraethylene glycol di (meth) acrylate or ethylene oxide-modified bisphenol A type di ( (Meth) acrylate and polypropylene glycol di (meth) acrylate are preferably used.

The mixing ratio of the ethylenically unsaturated compound (B) to 100 parts by weight of the base polymer (A) is 10 to
It is desirable to select from the range of 200 parts by weight, particularly 40 to 100 parts by weight. An insufficient amount of the ethylenically unsaturated compound (B) causes poor curing, a decrease in flexibility and a delay in the development speed, and an excessive amount of the ethylenically unsaturated compound (B) causes an increase in tackiness, cold flow, and peeling of the cured resist. This will cause a reduction in speed.

The photosensitive resin composition (A) comprises P, P, as a photopolymerization initiator in addition to the above components (A) and (B).
It contains P'-bis (dialkylamino) benzophenone (C), hexaarylbiimidazole (D) and a leuco dye (E) as a color former.
Specific examples of P, P'-bis (dialkylamino) benzophenone (C) include P, P'-bis (dimethylamino) benzophenone, P, P'-bis (diethylamino) benzophenone, and P, P'-bis ( Dibutylamino) benzophenone; and P, P'-bis (diethylamino) benzophenone is preferably used.

Also, hexaarylbiimidazole (D)
Are 2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'
-Biimidazole, 2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,1'
-Biimidazole, 2,2'-bis (o-fluorophenyl) -4,5,4 ', 5'-tetraphenyl-1,
1'-biimidazole, 2,2'-bis (o-methoxyphenyl) -4,5,4 ', 5'-tetraphenyl-
1,1′-biimidazole, 2,2′-bis (p-methoxyphenyl) -4,5,4 ′, 5′-tetraphenyl-1,1′-biimidazole, 2,4,2 ′, 4 '-Bis [bi (p-methoxyphenyl)]-5,5'-diphenyl-1,1'-biimidazole, 2,2'-bis (2,4-dimethoxyphenyl) -4,5,4', 5 '
-Diphenyl-1,1'-biimidazole, 2,2'-
Bis (p-methylthiophenyl) -4,5,4 ', 5'
-Diphenyl-1,1'-biimidazole, bis (2,
4,5-triphenyl) -1,1'-biimidazole, and the like. Further, 1,2'-, 1,4'-, and 2,4'- disclosed in JP-B-45-37377. Tautomers covalently bonded by the above can also be used, and among them, 2,2′-bis (o-chlorophenyl) -4,5
4 ', 5'-Tetraphenyl-1,2'-biimidazole is preferably used. Other photopolymerization initiators that can be used in combination with the photopolymerization initiators (C) and (D) include the same ones as described above.

Further, as the leuco dye (E), for example, bis (4-N, N-diethylamino-o-tolyl) methylenedylthiophenylmethane, bis (4-N, N-diethylamino-o-tolyl) benzylthio Examples include phenylmethane, leuco crystal violet, leucomalachite green, leucoaniline, leuco methyl violet, and among them, leuco crystal violet is suitably used.

The above components (C) to (E) are compounded in amounts of P, P'-bis (dialkylamino) based on 100 parts by weight of the total of the base polymer (A) and the ethylenically unsaturated compound (B). ) Benzophenone (C) is 0.01 to
0.25 parts by weight, preferably 0.05 to 0.2 parts by weight,
Hexaarylbiimidazole (D) is 1 to 10 parts by weight, preferably 2 to 6 parts by weight, and leuco dye (E) is 0.1 to 10 parts by weight.
0.5 to 2 parts by weight, preferably 0.1 to 1 part by weight,
If the component (C) is less than the above content, good surface hardness cannot be obtained and the chemical resistance decreases. Conversely, if the component (C) is more than the above content, the transmittance of ultraviolet rays decreases and sufficient internal curing is obtained. I can't. On the other hand, if the components (D) and (E) are less than the above contents, sufficient internal curing cannot be obtained. Conversely, if the contents are more than the above contents, it is difficult to dissolve at the time of mixing the dope, which is not preferable.

The photosensitive resin composition (including the photosensitive resin composition (a)) may further contain, if necessary, a thermal polymerization inhibitor, a plasticizer, a dye (dye, a color changing agent), and an adhesion promoter. , Antioxidants, solvents, surface tension modifiers, stabilizers, chain transfer agents,
Additives such as an antifoaming agent and a flame retardant 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.

As the pigment, in addition to the leuco dye used in the photosensitive resin composition (a), for example, brilliant green, eosin, methyl violet, ethyl violet, ethylene 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, Rakite Green, Malachite Green Lake, Patent Blue, Parafuchsin, Oil Blue # 603, Victoria Pure Blue BOH,
Spiron Blue GN, Rhodamine 6G, Roseaniline and the like. Of these, malachite green and brilliant green are preferred.

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.

The protective film used in the present invention comprises:
When the photoresist film is used in the form of a roll, the photosensitive resin composition layer having adhesiveness is transferred to the support film, or for the purpose of preventing dust or the like from adhering to the photosensitive resin composition layer. And a photosensitive resin composition layer. In the present invention, as such a protective film, the maximum roughness (R) of the surface in contact with the photosensitive resin composition layer
The greatest feature is that a film having y) of 2.0 μm or less is used, and other than the film, that is, the maximum roughness (R)
In the case of a film in which y) exceeds 2.0 μm, when the photosensitive resin composition layer is laminated on a substrate, the surface irregularities transferred from the protective film are not removed, resulting in voids, and the effect of the present invention is not exhibited. . On the other surface of the protective film, the maximum roughness (Ry) is not necessarily required to be 2.0 μm or less, and is not particularly limited.

Examples of the film having the maximum roughness (Ry) of 2.0 μm or less include a non-stretched polypropylene film, a biaxially stretched polypropylene film, and a polyethylene terephthalate film. Films are preferably used. The maximum roughness (Ry) of the film surface is measured according to JIS B0601. The thickness of the protective film is not particularly limited, but is usually 10 to 50 μm, preferably 10 to 30 μm.
μm is sufficient. Further, the protective film may be appropriately subjected to a release treatment as required.

Thus, in the present invention, the above support film,
A photoresist film is obtained by sequentially laminating a photosensitive resin composition layer (preferably using the photosensitive resin composition (a)) and a protective film. 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) The above-mentioned photosensitive resin composition (especially photosensitive resin composition (a)) is applied to a support film surface made of the above-mentioned polyester-based resin composition, and then from above the coated surface. A protective film is coated to form a photoresist film.

(Exposure) In order to form an image with a photoresist film, the protective film is peeled off, and the side of the photosensitive resin composition layer is coated with a copper-clad substrate, 42 alloy, SUS or the like.
After laminating on a metal surface such as that described above, exposure is performed by bringing a pattern mask into close contact with the other support film. According to the present invention, when laminating to such a substrate, it is possible to laminate without generating voids. 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, or the like is used.
After irradiation with ultraviolet rays, heating can be performed as necessary to complete the curing.

(Development) After exposure, the support film on the resist is peeled off and developed. When the photosensitive resin composition is a dilute alkali developing type, the development after exposure is carried out by using an alkali such as sodium carbonate, potassium carbonate or the like in an amount of 0.3 to 2% by weight.
It is carried out using a dilute aqueous solution of a certain degree. 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) In the etching, etching is generally performed using an acidic etching solution such as a cupric chloride-hydrochloric acid aqueous solution or a ferric chloride-hydrochloric acid aqueous solution. 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 or plating step, the remaining hardened resist is stripped off. 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 / photosensitive resin composition layer [preferably photosensitive resin composition (a) layer] / protective film, the protective film having a maximum roughness (Ry) of 2 in contact with the photosensitive resin composition layer. Since a film having a thickness of not more than 0.0 μm is used, an effect excellent in pattern formability is exhibited.

[0041]

The present invention will be described in more detail with reference to the following examples. Unless otherwise specified, “%” and “parts” are based on weight. Example 1 (Preparation of dope (photosensitive resin composition)) An ethylenically unsaturated compound (B) was added to 62 parts of the following base polymer (A1).
As tetraethylene glycol dimethacrylate 38
Parts, 0.1 part of P, P'-bis (diethylamino) benzophenone (C) as a photopolymerization initiator, 2,2'-bis (o-chlorophenyl) -4,5,4 ', 5'-tetraphenyl- 3.0 parts of 1,2′-biimidazole (D), 0.3 parts of leuco crystal violet (E) as a leuco dye, and 0.04 part of malachite green were blended and mixed well, and a dope (solvent: methyl ethyl ketone /
(Isopropyl alcohol = 85 parts / 15 parts).

Base polymer (A1) methyl methacrylate / n-butyl methacrylate / 2
A copolymer having a copolymerization ratio of -hydroxyethyl methacrylate / 2-ethylhexyl acrylate / methacrylic acid of 21/30/10/15/24 by weight (acid value 156.3, glass transition point 44.7 ° C, weight (Average molecular weight 80,000)

(Preparation of Photoresist Film) The above-mentioned dope (photosensitive resin composition) was coated on a support film (polyethylene terephthalate film (trade name: GS-16, manufactured by Teijin Limited) using an applicator having a gap of 7 mil.
Haze value 1.3%, maximum roughness (Ry) 0.6 μm, thickness 16 μm), and left at room temperature for 1 minute 30 seconds.
Each was dried in an oven at 60 ° C., 90 ° C. and 110 ° C. for 3 minutes to form a dry film having a resist thickness of 15 μm.
Further, as a protective film, a biaxially oriented polypropylene film (manufactured by Gunze Co., Ltd., trade name: NF) (maximum roughness (Ry):
0.9 μm, thickness: 20 μm) and a polyethylene terephthalate film [support film] /
A photoresist film of the present invention was obtained as a photosensitive resin composition layer / biaxially oriented polypropylene film [protective film]. After laminating the obtained photoresist film on a copper-clad laminate as described below, each performance was evaluated.

(Lamination on Copper-Clad Substrate) After this photoresist film was allowed to stand for 7 days, the protective film was peeled off and placed on a copper-clad substrate preheated to 60 ° C. in an oven at a laminating roll temperature of 100 ° C. and the same roll pressure. 3 kg / cm ² ,
Lamination was performed at a lamination speed of 1.0 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.

Each performance was evaluated as follows. (Void Amount Between Substrate and Photosensitive Resin Composition Layer) A central area of 100 mm × 100 mm of the laminated substrate was observed with a magnifying microscope, and the number of bubbles having a diameter of 10 μm or more was measured.

(Sensitivity) After lamination on a copper-clad substrate, an exposure machine (EXM-EXM-OAK) manufactured by Oak Manufacturing Co., Ltd. was used using a 21-step stofer step tablet (a negative film made so that the amount of light transmission was reduced stepwise). 1172-A00) with 20 kW ultra-high pressure mercury short arc lamp (parallel light)
Exposure was performed every mj. After a hold time of 15 minutes after exposure, development was carried out in a 1% aqueous sodium carbonate solution at 30 ° C. for 1.5 times the minimum development time. From each exposure dose and the number of steps remaining after development, an exposure dose (mj / cm ² ) sufficient to give 7 steps using a Stouffer 21-step tablet was examined.

(Resolution) After lamination on a copper-clad substrate, line / space = 1/1 (10, 15, 20, 25, 3
(0, 35, 40, 45, 50 μm) in close contact with a pattern mask (glass chrome dry plate) under vacuum.
The exposure was performed with an exposure amount equivalent to seven steps of a one-step tablet, and the minimum line width (μm) at which the resist image was resolved after development was examined. The development was performed in the same manner as in the sensitivity evaluation described above.

(Adhesion) After lamination on a copper-clad substrate, the line width was 10, 15, 20, 25, 30, 35, 40, 4
Using each of the pattern masks of 5, 50 μm (only one line—space width∞), development was performed in the same manner as in the evaluation of the resolution, and the minimum line width (μm) with good adhesion was examined.

(Pattern Formability) After lamination on a copper-clad substrate, a pattern mask of line / space = 30/30 μm was brought into close contact with a vacuum and exposed with an exposure amount equivalent to 7 steps of a 21-step stepper tablet. , After development,
Etching with copper chloride-hydrochloric acid etchant, 3%
After immersion in an aqueous solution of sodium hydroxide to remove the resist, the conductor pattern was observed with a magnifying microscope (line length: 100 mm × 10 lines). At this time, the number of defects and breaks was measured.

Example 2 In Example 1, an antistatic treated polyethylene terephthalate film (trade name: 22AQ45, manufactured by Toray Industries Inc.) was used in place of the biaxially stretched polypropylene film.
3%, thickness 22 μm), antistatic treated polyethylene terephthalate film [support film] / photosensitive resin composition layer / polyethylene terephthalate film (manufactured by Teijin Limited, GS-16, maximum roughness (Ry) 0.6 μm)
m, thickness: 16 μm) [Protective film] to prepare a photoresist film. The photosensitive resin composition was prepared in the same manner as in Example 1, except that 55 parts of the base polymer (A1) and 45 parts of ethylene oxide-modified bisphenol A-type dimethacrylate as the ethylenically unsaturated compound (B) were used. Those prepared in accordance with No. 1 were used. About the obtained photoresist film, it performed similarly to Example 1 and evaluated each performance.

Example 3 A vinylon film (trade name: BFU, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., trade name: BFU) (haze value: 0.8%%, thickness: 25 μm) was used in place of the biaxially stretched polypropylene film. Film [Supporting film] / Photosensitive resin composition layer / Polyethylene terephthalate film (manufactured by Teijin Limited, GS-16, maximum roughness (Ry) 0.6 μm, thickness 16 μm) [Protective film] Producing a photoresist film did. The photosensitive resin composition was prepared in the same manner as in Example 1, except that 55 parts of the base polymer (A1) and 45 parts of ethylene oxide-modified bisphenol A-type dimethacrylate as the ethylenically unsaturated compound (B) were used. Those prepared in accordance with No. 1 were used. About the obtained photoresist film, it performed similarly to Example 1 and evaluated each performance.

Example 4 In Example 1, the following base polymer (A2) was used
, 45 parts of tetraethylene glycol dimethacrylate as ethylenically unsaturated (B), 0.05 parts of P, P'-bis (diethylamino) benzophenone (C) as a photopolymerization initiator, 2,2'-bis (o) -Chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'
Using a photosensitive resin composition prepared according to Example 1 using 6.0 parts of biimidazole (D), 0.9 part of leuco crystal violet (E) as a leuco dye, and 0.04 part of malachite green. In the same manner as in Example 1, each performance was evaluated. Base polymer (A2) methyl methacrylate / n-butyl acrylate / 2-
Copolymer having a copolymerization ratio of ethylhexyl acrylate / methacrylic acid of 48/10/20/22 on a weight basis (acid value: 143.3, glass transition point: 40.1 ° C., weight average molecular weight: 75,000)

Example 5 In Example 1, the following base polymer (A3) was used
Parts, 40 parts of tetraethylene glycol dimethacrylate as the ethylenically unsaturated (B), 0.2 parts of P, P'-bis (diethylamino) benzophenone (C) as the photopolymerization initiator, 2,2'-bis (o) -Chlorophenyl) -4,5,4 ', 5'-tetraphenyl-1,2'
Using a photosensitive resin composition prepared according to Example 1 using 5.0 parts of biimidazole (D), 0.25 part of leuco crystal violet (E) as a leuco dye, and 0.04 part of malachite green. In the same manner as in Example 1, each performance was evaluated. The copolymerization ratio of the base polymer (A3) methyl methacrylate / n-butyl acrylate / styrene / methacrylic acid is 50/1 by weight.
5/10/25 copolymer (acid value 162.8, glass transition point 80.2 ° C, weight average molecular weight 60,000)

Comparative Example 1 In Example 1, a polyethylene film (trade name: GF12, manufactured by Tamapoli Co.) (maximum roughness (Ry): 2.5 μm)
m, thickness: 28 μm) was used in the same manner except that the protective film was used, and each performance was evaluated. Table 1 shows the results of Examples and Comparative Examples.

[0055]

Table 1 Void Amount Sensitivity Resolution Adhesion Pattern Exposure Amount Line Width Line Width Formability (pcs) (mj / cm ² ) (μm) (μm) (pcs) Example 1 13 300 20 150 Example 2 29 120 30 150 Example 3 18 100 25 200 Example 4 25 350 25 150 Example 5 32 250 20 300 Comparative example 1 208 300 20 15 3

[0056]

The photoresist film obtained according to the present invention is excellent not only in sensitivity, resolution and adhesion, but also in pattern formation, so that it can be used for manufacturing printed wiring boards.
It is very useful as an etching resist or plating resist corresponding to high fineness and high definition, such as lead frame manufacturing and precision metal processing.

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[Procedure amendment]

[Submission date] April 5, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0016

[Correction method] Change

[Correction contents]

[0016] As the photopolymerization initiator, Baie benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n- butyl ether, benzoin phenyl ether, benzoin isobutyl ether, benzyl diphenyl disulfinate de,
Dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,3'-dimethyl-4-methoxybenzophenone, benzophenone, p, p'-bis (dimethylamino) benzophenone, p, p'-bis (diethylamino) benzophenone, Pibaroin'echiru Ether, 1,
1-dichloroacetophenone, pt-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-methyl-1-propanone, 2-methyl- [4
-(Methylthio) phenyl] -2-morpholino-1-
Propanone, tribromophenylsulfone, tribromomethylphenylsulfone, N-phenylglycine, 2,
4,6- [tris (trichloromethyl) -1,3,5
-Triazine, 2,4- [bis (trichloromethyl)]-
6- (4'-methoxyphenyl) -1,3,5-triazine, 2,4- [bis (triclomethyl)]-6- (4 '
-Methoxynaphthyl) -1,3,5-triazine, 2,
-[Bis (trichloromethyl)]-6- (piperonyl)-
1,3,5-triazine 2,4- [bis (trichloromethyl)]-6- (4′-methoxystyryl) -1,3,3
Triazine derivatives such as 5-triazine and acridine;
Acridine derivatives such as 9-phenylacridine;
2'-bis (o-chlorophenyl) -4,5,4 ',
5′-tetraphenyl-1,2′-biimidazole,
2,2′-bis (o-chlorophenyl) -4,5
4 ′, 5′-tetraphenyl-1,1′-biimidazole, 2,2′-bis (o-fluorophenyl) -4,
5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (o-methoxyphenyl)-
4,5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,2'-bis (p-methoxyphenyl)
-4,5,4 ', 5'-tetraphenyl-1,1'-biimidazole, 2,4,2', 4'-bis [bi (p-methoxyphenyl)]-5,5'-diphenyl- 1,1 '
-Biimidazole, 2,2'-bis (2,4-dimethoxyphenyl) -4,5,4 ', 5'-diphenyl-1,
1′-biimidazole, 2,2′-bis (p-methylthiophenyl) -4,5,4 ′, 5′-diphenyl-1,
Examples include hexaarylbiimidazoles such as 1'-biimidazole and bis (2,4,5-triphenyl) -1,1'-biimidazole, and these are used alone or in combination of two or more.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0046

[Correction method] Change

[Correction contents]

(Sensitivity) After lamination on a copper-clad substrate, an exposure machine (EXM-EXM-OAK) manufactured by Oak Manufacturing Co., Ltd. was used using a 21-step stofer step tablet (a negative film made so that the amount of light transmission was reduced stepwise). 1172-A00) with 20 kW ultra-high pressure mercury short arc lamp (parallel light)
Exposure was performed every mj. After a hold time of 15 minutes after the exposure, development was carried out in a 1% aqueous sodium carbonate solution at 30 ° C. for 1.5 times the minimum development time. From each exposure dose and the number of steps remaining after development, an exposure dose (mj / cm ² ) sufficient to give 7 steps using a Stouffer 21-step tablet was examined.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

Example 3 A vinylon film (having a haze value of 0.8% and a thickness of 25 μm) (a haze value of 0.8% and a thickness of 25 μm) was used in Example 1 instead of the biaxially stretched polypropylene film. [Support film] / Photosensitive resin composition layer / Polyethylene terephthalate film (manufactured by Teijin Limited, GS-16, maximum roughness (Ry) 0.6 μm, thickness 16 μm) [Protective film] A photoresist film was prepared. . The photosensitive resin composition was prepared in the same manner as in Example 1, except that 55 parts of the base polymer (A1) and 45 parts of ethylene oxide-modified bisphenol A-type dimethacrylate as the ethylenically unsaturated compound (B) were used. Those prepared in accordance with No. 1 were used. About the obtained photoresist film, it performed similarly to Example 1.
Each performance was evaluated.

Claims (5)

[Claims] 1. support film / photosensitive resin composition layer /
A photoresist film comprising a protective film, wherein a film having a maximum roughness (Ry) of 2.0 μm or less on a surface in contact with a photosensitive resin composition layer is used as the protective film. 2. The photoresist film according to claim 1, wherein the protective film is a polypropylene film or a polyethylene terephthalate film. 3. The photosensitive resin composition has an acid value of 100.
Weight average molecular weight of 30000 at ~ 200 mgKOH / g
~ 120,000 base polymer (A), ethylenically unsaturated compound (B), P, P'-bis (dialkylamino) benzophenone (C), hexaarylbiimidazole (D) and leuco dye (E). , (A)
(C) is 0.01 with respect to 100 parts by weight in total of (B) and (B).
0.25 parts by weight, (D) 1.0-10 parts by weight,
3. The photoresist film according to claim 1, wherein a photosensitive resin composition containing 0.05 to 2% by weight of (E) is used. 4. As the ethylenically unsaturated compound (B),
The photoresist film according to claim 3, comprising a material selected from tetraethylene glycol di (meth) acrylate, ethylene oxide-modified bisphenol A type di (meth) acrylate, and polypropylene glycol di (meth) acrylate. 5. A support film having a haze value of 0.5.
The photoresist film according to claim 1, wherein a film having a content of 01 to 4.0% is used.