TWI526783B - A photosensitive resin composition and a laminate - Google Patents

Description

Photosensitive resin composition and laminate thereof

The present invention relates to a photosensitive resin composition which can be developed by an aqueous alkaline solution, a photosensitive resin composition laminated body in which the photosensitive resin composition is laminated on a support, and a laminated body using the photosensitive resin composition. A method of forming a photoresist pattern on a substrate, and a use of the photoresist pattern.

More specifically, it relates to the manufacture of a printed circuit board, the manufacture of a flexible printed circuit board, the manufacture of a lead frame for IC chip mounting (hereinafter referred to as a lead frame), and the precision processing of a metal foil such as a metal mask. , semiconductor package such as BGA (spherical array) or CSP (wafer size package), TAB (Tape Automated Bonding) or COF (Chip On Film): semiconductor IC mounted on a film-like micro-board Manufactured by the manufacturer of the tape substrate, the manufacture of semiconductor bumps, the manufacture of ITO (Indium Tin Oxides) electrodes, address electrodes, electromagnetic wave masks, etc. in the field of flat panel displays, or by sandblasting A protective cover member for processing a substrate, and a photosensitive resin composition having a preferable photoresist pattern.

Previously, printed circuit boards were manufactured by photolithography. The photolithography method is a method in which a photosensitive resin composition is applied onto a substrate, pattern exposure is performed to cure and cure the exposed portion of the photosensitive resin composition, and the unexposed portion is removed by a developing solution to form light on the substrate. The resist pattern is formed by etching or plating to form a conductor pattern, and then removing the photoresist pattern from the substrate to form a conductor pattern on the substrate.

In the photolithography method, when the photosensitive resin composition is applied onto a substrate, a method in which a photoresist solution is applied to a substrate to be dried, or a layer containing a support or a photosensitive resin composition is used ( Hereinafter, any one of the methods of laminating a photosensitive resin laminate (hereinafter referred to as "dry film photoresist") which is sequentially laminated with a protective layer as needed, on the substrate is referred to as a "photosensitive resin layer". Moreover, in the manufacture of printed circuit boards, the latter dry film photoresist is often used.

The above method of manufacturing a printed circuit board using dry film photoresist is as follows.

First, when the dry film photoresist has a protective layer such as a polyethylene film, it is peeled off from the photosensitive resin layer. Then, a layered photosensitive resin layer and a support are laminated on a substrate such as a copper foil laminate using a laminator so as to be in the order of the substrate, the photosensitive resin layer, and the support. Then, the photosensitive resin layer is exposed to ultraviolet light containing i-rays (365 nm) emitted from an ultrahigh pressure mercury lamp via a mask having a wiring pattern, whereby the exposed portion is polymerized and cured. Then, a support containing polyethylene terephthalate or the like is peeled off. Then, the unexposed portion of the photosensitive resin layer is dissolved or dispersed by a developing solution such as a weakly alkaline aqueous solution to form a photoresist pattern on the substrate. Then, the formed photoresist pattern is subjected to a known etching treatment or pattern plating treatment as a protective cover. Finally, the photoresist pattern is peeled off from the substrate to fabricate a substrate having a conductor pattern, that is, a printed circuit board.

On the other hand, in order to produce a wiring having a uniform conductor shape and high density, a semi-additive method is used. In the semi-additive method, first, a photoresist pattern is formed on the seed copper film by the above method. Then, plating is performed between the photoresist patterns to form a plated copper wiring, and the photoresist is peeled off, and the plated copper wiring and the seed copper thin film are simultaneously etched by a method called flash etching. The semi-additive method is different from the pattern plating method in that the seed copper film is thin. Therefore, it is possible to produce a rectangular and high-density wiring with almost no influence of etching.

Previously, the semi-additive method was a manufacturing method for the purpose of high-density wiring, and high resolution was an important performance.

In Patent Document 1 below, the sensitization of a quaternary copolymer containing methacrylic acid/methyl methacrylate/butyl acrylate/2-ethylhexyl acrylate and tricyclodecane dimethanol dimethacrylate is used. The resolution of the resin composition is disclosed, but the resolution and the adhesion are not sufficient for the current situation.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2001-154348

An object of the present invention is to provide a photosensitive resin composition which is particularly excellent in high resolution and adhesion as a photoresist material such as an etching resist or a plating resist, and a photosensitive resin laminate using the same.

The present inventors have repeatedly conducted various studies, and as a result, it has been found that high resolution can be achieved by controlling the water contact angle and the Young's modulus of the cured product obtained by exposing and developing the photosensitive resin composition to specific values. Excellent adhesion to the present invention. That is, the present invention is as follows:

[1] A photosensitive resin composition comprising (A) a binder polymer: 20 to 90% by weight, (B) a photopolymerizable compound: 5 to 75% by weight, and (C) light Polymerization initiator: 0.01 to 30% by weight of the photosensitive resin composition; the above (A) binder polymer is obtained by using the first one of a carboxylic acid or a carboxylic anhydride having one polymerizable unsaturated group in the molecule a copolymer having a weight average molecular weight of at least 5,000 to 100,000 obtained by at least copolymerizing a second monomer having one polymerizable unsaturated group and a non-acidic group in the molecule, and the (B) photopolymerizable compound has a molecule An addition polymerizable monomer having at least one terminal ethylenically unsaturated group, and exposing the photosensitive resin composition to an exposure amount of 5 stages of a 21-stage Stuart-type exposure meter, followed by using 1% by mass of sodium carbonate The water contact angle of the photosensitive resin layer obtained by developing the aqueous solution (30 ° C) at twice the minimum development time exceeded 60°, and the Young's modulus was 1.5 GPa or more and less than 4 GPa.

[2] The photosensitive resin composition according to the above [1], wherein the (A) binder polymer is a phenyl group-containing copolymer or a cyclohexyl group-containing copolymer.

[3] The photosensitive resin composition according to the above [1] or [2] wherein the photosensitive resin layer has a Young's modulus of 2 GPa or more and less than 4 GPa.

[4] The photosensitive resin composition according to any one of the above [1] to [3] wherein the photosensitive resin layer has a Young's modulus of 3 GPa or more and less than 4 GPa.

[5] The photosensitive resin composition according to any one of the above [1] to [4] wherein the (C) photopolymerizable initiator contains a 2,4,5-triarylimidazole dimer.

[6] A photosensitive resin laminate which is obtained by laminating a photosensitive resin composition according to any one of the above [1] to [5] on a support.

[7] A method of forming a resist pattern, comprising a layer forming step of forming a layer of the photosensitive resin composition according to any one of the above [1] to [5] on a substrate, an exposure step, and development step.

[8] The method according to [7] above, wherein in the exposure step, the photosensitive resin layer is directly drawn using a photosensitive resin composition to be exposed.

[9] A method of manufacturing a printed circuit board comprising the step of etching or plating a substrate on which a photoresist pattern is formed by the method for forming a photoresist pattern according to [7] or [8] above.

[10] A method for producing a substrate having a concave-convex pattern, comprising: a substrate having a photoresist pattern formed by the method for forming a photoresist pattern according to [7] or [8] described above, which is processed by sand blasting step.

[11] A method of manufacturing a semiconductor package or bump, comprising the step of etching or plating a substrate on which a photoresist pattern is formed by a method for forming a photoresist pattern according to [7] or [8] above .

[12] A method of manufacturing a lead frame, comprising the step of etching or plating a substrate on which a photoresist pattern is formed by the method for forming a photoresist pattern according to [7] or [8] above.

[13] A cured resin composition obtained by curing the photosensitive resin composition according to any one of the above [1] to [5].

[14] A resin cured product laminate comprising a cured resin of the above [13] on a support.

The photosensitive resin composition of the present invention, the photosensitive resin laminate, and the photoresist pattern obtained by using the formation method of the photoresist pattern have a water contact angle of more than 60° and a Young's modulus of 1.5 GPa or more. It has a specific characteristic of less than 4 GPa, and therefore has excellent high resolution and adhesion.

Hereinafter, the present invention will be specifically described.

In order to obtain a photoresist pattern having high resolution and excellent adhesion, the water contact angle of the cured product obtained by subjecting the photosensitive resin composition of the present invention to exposure and development must exceed 60°, and the Young's modulus thereof must be 1.5 GPa or more, less than 4 GPa, preferably 2 GPa or more, less than 4 GPa, more preferably 3 GPa or more, less than 4 GPa.

When the water contact angle exceeds 60°, the cured portion after exposure does not swell, the rinsing property during development is excellent, and the resolution is good, and the Young's modulus is 1.5 GPa or more. 4 GPa, the photoresist pattern at the time of development is excellent in stand-up property, and if it is 2 GPa or more and less than 4 GPa, the erectability is further improved, and if it is 3 GPa or more and less than 4 GPa, it rises. Sex became even better.

The water contact angle of the cured product obtained by subjecting the photosensitive resin composition of the present invention to exposure and development must exceed 60°. From the viewpoint of the upper limit of self-developability, it is preferably 95 or less, more preferably 80 or less, further preferably 70 or less, and most preferably 65 or less. The lower limit is preferably 62° or more, and more preferably 63° or more from the viewpoint of preventing swelling at the time of self-development and improving resolution. On the other hand, from the viewpoint of preventing swelling of the cured portion after exposure, improving the rinsing property at the time of development, and improving the resolution, the concept of controlling the water contact angle to a specific value does not exist in the prior art. Further, the cured product obtained by subjecting the photosensitive resin composition of the present invention to exposure and development must have a Young's modulus of 1.5 GPa or more and less than 4 GPa. When the Young's modulus is 1.5 GPa or more, the photoresist pattern is excellent in stand-up property, and if it is less than 4 GPa, the photoresist pattern is excellent in adhesion. The present invention is based on the fact that the water contact angle and the Young's modulus are both controlled to a specific value, and the resolution and adhesion of the cured product obtained by exposing and developing the photosensitive resin composition can be remarkably improved, and it is confirmed. The effect is completed.

In this specification, the "water contact angle" is specifically based on JIS R3257, using the optical mirror (automatic) contact angle measuring instrument DropMaster DM500 manufactured by Kyowa Interface Science Co., Ltd., to make 1.5 μl of water droplets from the needle. The surface of the photosensitive resin composition on the substrate which was formed by exposing and developing the resin composition to be measured was placed on the substrate, and the measurement was carried out 60 seconds after the contact of the water droplets.

In the present specification, the "Young's modulus" can be measured by a nanoindenter DCM manufactured by Toyo-Technica Co., Ltd. by a nanoindentation method. Specifically, the "Young's modulus" is a surface of a photosensitive resin composition on a substrate obtained by laminating a resin composition to be measured on a substrate and exposing and developing the substrate, using a nanometer manufactured by Toyo-Technica Co., Ltd. The indenter DCM was measured. As a measurement method, use DCM Basic Hardness, Modulus, Tip Cal, Load Control. msm (MultiLoad‧Unload‧Method, MultiLoad Method), the parameters of the indentation test are Percent To Unload=90% (unloading percentage), Maximum Load ( Maximum load) = 1 gf, Load Rate Multiple For Unlosd Rate = 1, Number Of Times to Load = 5, Peak Hold time = 10 s, Time To Load (load time) = 15 s, Poisson's ratio = 0.25. The Young's modulus is the value of "Modulas At Max Load".

(A) binder polymer

The resin for the (A) binder polymer used in the present invention is obtained by copolymerizing one or more monomers selected from the following two monomers.

The first monomer is a carboxylic acid or an acid anhydride having one polymerizable unsaturated group in the molecule. For example, (meth)acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, and a maleic acid half ester are mentioned.

The second monomer is a compound which is non-acidic and has one polymerizable unsaturated group in the molecule. This compound is selected so as to maintain various properties such as developability of the photosensitive resin layer, resistance in etching and plating steps, and flexibility of the cured film.

The resin used for the (A) binder polymer used in the present invention may, for example, be styrene and a styrene derivative such as α-methylstyrene, p-hydroxystyrene, p-methylstyrene or p-methoxy. Styrene, p-chlorostyrene, benzyl (meth)acrylate, 4-hydroxybenzyl (meth)acrylate, 4-methoxybenzyl (meth)acrylate, 4-methyl (meth)acrylate Benzyl ester, 4-chlorobenzyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, cyclohexyl (meth)acrylate, (a) Base) n-butyl acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate Ester, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, (meth) acrylamide, N-methylol acrylamide, N-butoxy methacrylamide Further, (meth)acrylonitrile or glycidyl (meth)acrylate may be used alone or in combination of two or more.

The resin for the (A) binder polymer used in the present invention is preferably synthesized by mixing the above first monomer and the second monomer in a solvent such as acetone or methyl b. In a solution obtained by diluting a ketone or isopropyl alcohol, a radical polymerization initiator such as benzoyl peroxide or azoisobutyronitrile is added in an appropriate amount to carry out superheating and stirring. There is also a case where a part of the mixture is added dropwise to the reaction liquid for synthesis. After the reaction is completed, a solvent is further added to adjust the concentration to a desired concentration. As the synthesis method, in addition to solution polymerization, bulk polymerization, suspension polymerization or emulsification superposition can also be used.

The amount of the carboxyl group contained in the resin for the (A) binder polymer of the present invention is preferably 100 or more and 600 or less, more preferably 250 or more and 450 or less, in terms of acid equivalent. The acid equivalent refers to the mass of the resin for the binder having one equivalent of the carboxyl group.

In order to impart developability or releasability to an aqueous alkali solution to the photopolymerizable resin layer, it is necessary to have a carboxyl group in the resin for a binder. The acid equivalent of the carboxyl group in the resin for the adhesive is 100 or more from the viewpoint of improving the development resistance and improving the resolution and the adhesion, and is 600 or less from the viewpoint of improving developability and peelability. The acid equivalent was measured by a potentiometric titration method using a Hirouma automatic titrator (COM-555) manufactured by Hiranuma Co., Ltd. using 0.1 mol/L sodium hydroxide.

The (A) binder polymer used in the present invention has a weight average molecular weight of 5,000 to 500,000. The weight average molecular weight is 500,000 or less from the viewpoint of improving the developability and the resolving property, and the photosensitive resin composition oozes from the end surface of the roll when the photosensitive resin laminated body is wound into a roll shape. The phenomenon, that is, the edge fuse, is 5,000 or more. In order to further exert the effects of the present invention, the weight average molecular weight of the resin for the binder is 5,000 to 100,000, preferably 5,000 to 60,000.

The weight average molecular weight is a gel dialysis chromatograph (GPC) manufactured by Japan Spectrophotometer (pump: Gulliver, PU-1580, column: Shodex (registered trademark) manufactured by Showa Denko Co., Ltd. (KF- 807, KF-806M, KF-806M, KF-802.5) 4 in series, moving bed solvent: tetrahydrofuran, using a calibration curve based on polystyrene standard sample (Shodex STANDARD SM-105 manufactured by Showa Denko) It is obtained as a polystyrene conversion.

The ratio of the resin for the (A) binder polymer used in the present invention to the total of the photosensitive resin composition (solid content, the same applies hereinafter) is in the range of 20 to 90% by mass, preferably 30%. 70% by mass. The photoresist pattern formed by exposure and development has a characteristic as a photoresist, and is, for example, a cap hole, an etching, and sufficient resistance in various plating steps, and is 20% by mass or more and 90%. Below mass%.

The monomer constituting the resin for the (A) binder polymer used in the present invention may be selected from a monomer containing a phenyl group or a monomer having a cyclohexyl group. Preferred are monomers containing a phenyl group. In order to make the water contact angle of the photosensitive resin layer after curing the photosensitive resin composition exceed 60°, an effective method is to use a binder polymer containing a monomer containing a phenyl group or a monomer containing a cyclohexyl group. The content ratio of the phenyl group-containing monomer or the cyclohexyl group-containing monomer of the binder polymer in the photosensitive resin composition is preferably from 5 to 95% by mass, more preferably from 10 to 85% by mass.

As the resin for the (A) binder polymer used in the present invention, for example, α-methylstyrene, p-hydroxystyrene, p-methylstyrene, p-methoxystyrene, p-chloro is preferable. Styrene, benzyl (meth)acrylate, 4-hydroxybenzyl (meth)acrylate, 4-methoxybenzyl (meth)acrylate, 4-methylbenzyl (meth)acrylate, (methyl) ) 4-chlorobenzyl acrylate, cyclohexyl (meth) acrylate.

(B) Photopolymerizable compound

The (B) photopolymerizable compound used in the present invention is an addition polymerizable monomer having at least one terminal ethylenically unsaturated group. The addition polymerizable monomer of the (B) photopolymerizable compound used in the photosensitive resin composition of the present invention may, for example, be 4-nonylphenylheptaethylene glycol dipropylene glycol acrylate or acrylic acid 2 -Hydroxy-3-phenoxypropyl ester, phenoxy hexaethylene glycol acrylate, phthalic anhydride and 2-hydroxypropyl acrylate half ester compound and propylene oxide reaction (manufactured by Nippon Shokubai Chemical Co., Ltd. Trade name OE-A 200), 4-n-octylphenoxypentapropylene glycol acrylate, 2,2-bis[{4-(methyl)acryloxycarbonylpolyethoxy]phenyl]propane, 2, 2-bis{(4-propenyloxypolyethoxy)cyclohexyl}propane or 2,2-bis{(4-methylpropenyloxypolyethoxy)cyclohexyl}propane, 1,6- Hexanediol (meth) acrylate, 1,4-cyclohexanediol di(meth) acrylate, polypropylene glycol di(meth) acrylate, polyethylene glycol di(meth) acrylate, polyoxygen Polyoxyalkylene glycol di(meth)acrylate such as ethylene polyoxypropylene glycol di(meth)acrylate, 2-di(p-hydroxyphenyl)propane di(meth)acrylate, glycerol tris(methyl) Acrylate, urethane-containing group a base (meth) acrylate such as a urethane compound of hexamethylene diisocyanate and pentapropylene glycol monomethacrylate, a polyfunctional (meth) acrylate of an isomeric cyanurate compound, a tricyclic ring Decane dimethanol diacrylate and tricyclodecane dimethanol dimethacrylate.

The amount of the (B) addition polymerizable monomer contained in the photosensitive resin composition of the present invention is in the range of 5 to 75% by mass, more preferably in the range of 15 to 70, based on the total amount of the photosensitive resin composition. quality%. The amount is 5% by mass or more from the viewpoint of suppressing the hardening failure and the development time, and is 75 mass% or less from the viewpoint of suppressing the cold flow and the peeling delay of the cured photoresist.

The photopolymerizable compound (B) used in the present invention has a Young's modulus of 2 GPa or more and less than 4 GPa, and preferably has an ethylenically unsaturated bond concentration of the photosensitive resin composition. The range of 0.01 mol/100 g~0.1 mol/100 g.

The ethylenically unsaturated bond concentration D in the photosensitive resin can be determined from the following formula.

D=(E ₁ ×F ₁ ×100)/(Mw ₁ ×G)+(E ₂ ×F ₂ ×100)/(Mw ₂ ×G)+‧‧‧‧+(E _n ×F _n ×100) /(Mw _n ×G)

In the formula,

D: concentration of ethylene unsaturated groups (mol/100 g) with respect to 100 g of the photosensitive resin composition

E ₁ ‧‧‧E _n : blending amount

F ₁ ‧‧‧F _n : number of polymerization ends

Mw ₁ ‧‧‧Mw _n : weight average molecular weight of photopolymerizable compound

n: number of formulated photopolymerizable compounds

G: total weight of the photosensitive resin composition

In order to set the Young's modulus of the photosensitive resin composition to 2 GPa or more and less than 4 GPa, an effective method is to use a photopolymerizable compound having three or more double bonds or a photopolymerizable compound having a molecular weight of 600 or less. The content of the binder polymer and the polymerizable compound is 20% by mass or less.

Specifically, a 7:3 mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (M-306, manufactured by Toagosei Co., Ltd., product name), and an average of 3 moles of ethylene oxide added to trimethylolpropane may be mentioned. Triacrylate (A-TMPT-3EO, manufactured by Shin-Nakamura Chemical Co., Ltd., product name), urethane ester of hexamethylene diisocyanate and polypropylene glycol monomethacrylate, tricyclodecane dimethanol Acrylate (NK Ester DCP, manufactured by Shin-Nakamura Chemical Co., Ltd., product name), and dimethyl acrylate of ethylene oxide having an average of 2 moles of ethylene oxide per bisphenol A (BPE-200, product name of Xinzhongcun Chemical Manufacturing).

In the (B) photopolymerizable compound used in the present invention, the water contact angle of the photosensitive resin layer after curing the photosensitive resin composition exceeds 60°, and an effective method is to use a light having one double bond number. The content of the polymerizable compound is 10% by mass or less based on the total mass parts of the binder polymer and the polymerizable compound.

In addition, in order to make the water contact angle of the photosensitive resin layer after hardening the photosensitive resin composition more than 60 degrees, the effective method (B) photopolymerizable compound contains the following general formula (II) and / or the following formula Photopolymerizable compound represented by (III):

[Chemical 1]

In the formula, R ₁ and R ₂ are each independently a hydrogen atom or a methyl group, and A and B represent an alkylene group having a carbon number of 2 to 6. These may be the same or different, and in different cases, - (AO) The repeating unit of - and - (BO)- may be a block structure or a random structure, and m1, m2, m3, and m4 are 0 or a positive integer, and the total of these is 2 to 40},

[Chemical 2]

In the formula, R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group, and A and B represent an alkylene group having a carbon number of 2 to 6, which may be the same or different, and in different cases, - (AO) The repeating unit of - and -(BO)- may be a block structure or a random structure, and m5, m6, m7, and m8 are 0 or a positive integer, and the total of these is 0 to 40, and R ⁵ is a halogen atom. Or an alkyl group having a carbon number of 1 to 3, and n is 0 to 14}. The content of the (B) photopolymerizable compound represented by the formula (II) or (III) is preferably 10% by mass or more, and more preferably 20% by mass based on the total mass parts of the binder polymer and the polymerizable compound. the above.

(C) Photopolymerization initiator

From the viewpoint of high resolution, a preferred embodiment is (C) a photopolymerization initiator used in the present invention, and contains at least one 2,4,5-triaryl represented by the following formula (I). Imidazole dimer:

[Chemical 3]

In the formula, X, Y and Z each independently represent a group selected from the group consisting of hydrogen, an alkyl group having 1 to 5 carbon atoms, an alkoxy group, and a halogen group, and p, q and r are each independently An integer from 1 to 5}.

In the compound represented by the above formula (I), the covalent bond of the two octyl groups bonded is located at 1,1'-, 1, 2'-, 1, 4'-, 2, 2'-, 2, The 4'- or 4,4'-position is preferably a compound located at the 1,2'-position. As the 2,4,5-triaryl imidazole dimer, for example, 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., particularly preferably 2-(o-chlorobenzene) Base 4,5-diphenylimidazole dimer.

In the case where the photosensitive resin composition of the present invention contains at least one of the 2,4,5-triarylimidazole dimers represented by the above formula (I), the ratio is preferably from 0.1 to 20% by mass. From the viewpoint of self-resolution and adhesion, it is 0.1% by mass or more, and is 20% by mass or less from the viewpoint of self-developing cohesiveness. A more preferable range is 0.5 to 15% by mass, and a good range is 1 to 10% by mass.

As the (C) photopolymerization initiator used in the present invention, it is preferred to use the 2,4,5-triarylimidazole dimer represented by the above formula (I) in combination with p-aminophenyl ketone. system. Examples of the p-aminophenyl ketone include p-aminodiphenyl ketone, p-butylaminoacetophenone, p-dimethylaminoacetophenone, and p-dimethylaminodiphenyl ketone. p,p'-bis(ethylamino)diphenyl ketone, p,p'-bis(dimethylamino)diphenyl ketone [micilenone], p,p'-double (diethyl Amino)diphenyl ketone, p,p'-bis(dibutylamino)diphenyl ketone.

Further, it is also preferred to use a pyrazoline compound such as 1-phenyl-3-(4-t-butyl-styryl)-5-(4-t-butyl-phenyl)-pyrazoline. The embodiment.

Further, in addition to the above-mentioned compounds, other photopolymerization initiators may be used in combination. The photopolymerization initiator herein refers to a compound which can be activated by various active rays such as ultraviolet rays to initiate polymerization.

As other photopolymerization initiators, there are hydrazines such as 2-ethyl hydrazine, 2-tert-butyl fluorene, aromatic ketones such as diphenyl ketone, benzoin, benzoin ethers, such as benzoin methyl ether. , benzoin ethyl ether, acridine compounds, such as 9-phenyl acridine, benzil dimethyl ketal, benzoin diethyl ketal.

Further, there may be, for example, thioxanthone such as thioxanthone, 2,4-diethylthiaxanone or 2-chlorothiazinone, and a tertiary amine compound such as dimethylamino group. A combination of alkyl benzoate compounds.

Also, there are oxime esters such as 1-phenyl-1,2-propanedione-2-O-benzimidoxime, 1-phenyl-1,2-propanedione-2-(O-B Oxycarbonyl) hydrazine. Further, an N-aryl-α-amino acid compound can also be used, and among these, N-phenylglycine is particularly preferred.

The ratio of the (C) photopolymerization initiator contained in the photosensitive resin composition of the present invention is 0.01 to 30% by mass. If the ratio is less than 0.01% by mass, sufficient sensitivity cannot be obtained. In addition, when the ratio exceeds 30% by mass, fogging due to diffraction of light passing through the photomask is apt to occur at the time of exposure, and as a result, the resolution is deteriorated. The content thereof is more preferably 0.1 to 15% by mass, and further preferably 0.1 to 10% by mass.

(D) Other ingredients

In order to visualize the contrast after exposure (identification of the exposed portion and the unexposed portion), the photosensitive resin composition of the present invention may contain a leuco dye. The content in the case of containing a leuco dye is preferably from 0.1 to 10% by mass. As such a leuco dye, tris(4-dimethylamino-2-methylphenyl)methane [leuco crystal violet], tris(4-dimethylamino-2-methylbenzene) Base) methane [hidden malachite green], arro dye. Among them, in the case of using leuco crystal violet, the contrast is good, and it is preferable.

The above-mentioned leuco dye and halide are used in combination in the photosensitive resin composition, and are a preferred embodiment of the present invention from the viewpoint of adhesion and contrast.

Examples of the halide include bromopentane, bromoisopentane, 1,2-dibromo-2-methylpropane, 1,2-dibromoethane, diphenylbromomethane, dibrominated toluene, and the like. Methyl bromide, tribromomethylphenyl hydrazine, carbon tetrabromide, tris(2,3-dibromopropyl) phosphate, trichloroacetamide, iodopentane, iodoisobutane, 1,1,1- Trichloro-2,2-bis(p-chlorophenyl)ethane, hexachloroethane, halogenated three Compound. As the halogenated three The compound may, for example, be 2,4,6-tris(trichloromethyl)-all three , 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-all three .

In the case of containing a halide, the content of the halide in the photosensitive resin composition is preferably from 0.01 to 10% by mass.

In order to improve the handleability of the photosensitive resin composition, in addition to the above leuco dye, the following coloring matter may be added. As such a coloring substance, for example, poinsettia, phthalocyanine green, golden amine base, p-magenta, crystal violet, methyl orange, Nero blue 2B, Victoria blue, malachite green (Hodogaya Chemical) Aizen (registered trademark) MALACHITE GREEN), alkaline blue 20, diamond green (Aizen (registered trademark) DIAMOND GREEN GH manufactured by Hodogaya Chemical Co., Ltd.).

The amount of the coloring matter to be added is preferably 0.001 to 1% by mass in the photosensitive resin composition. When the content is 0.001% by mass or more, the effect of improving workability is obtained, and when it is 1% by mass or less, the effect of maintaining storage stability is obtained.

Among them, useful is the combination of tribromomethylphenyl hydrazine and leuco dye or three A combination of a compound and a leuco dye.

Further, in order to improve the thermal stability and storage stability of the photosensitive resin composition of the present invention, it is preferred to contain a radical polymerization inhibitor, a benzotriazole, and a carboxybenzoic acid in the photosensitive resin composition. At least one or more compounds of the group consisting of triazoles.

Examples of such a radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, t-butylcatechol, cuprous chloride, and 2,6-di. Third butyl-p-cresol, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-methylenebis(4-ethyl-6- Third butyl phenol), nitrosophenylhydroxylamine ammonium salt, diphenyl nitrosamine.

Further, examples of the benzotriazoles include 1,2,3-benzotriazole, 1-chloro-1,2,3-benzotriazole, and bis(N-2-ethylhexyl)amine. Chiatyl-1,2,3-benzotriazole, bis(N-2-ethylhexyl)aminomethylene-1,2,3-toluene triazole, and bis(N-2-hydroxyl) Ethyl)aminomethylene-1,2,3-benzotriazole.

Further, examples of the carboxybenzotriazoles include 4-carboxy-1,2,3-benzotriazole, 5-carboxy-1,2,3-benzotriazole, and N-(N,N. -di-2-ethylhexyl)aminomethylenecarboxybenzotriazole, N-(N,N-di-2-hydroxyethyl)aminomethylenecarboxybenzotriazole, N-(N , N-di-2-ethylhexyl)amine-extended ethylcarboxybenzotriazole.

The total amount of the radical polymerization inhibitor, the benzotriazole or the carboxybenzotriazole is preferably 0.01 to 3% by mass, more preferably 0.05 to 1% by mass in the photosensitive resin composition. . The amount is preferably 0.01% by mass or more from the viewpoint of imparting storage stability to the photosensitive resin composition, and more preferably 3% by mass or less from the viewpoint of maintaining sensitivity.

A plasticizer may be contained in the photosensitive resin composition of the present invention as needed. Examples of such a plasticizer include polyethylene glycol, polypropylene glycol, polyoxypropylene polyoxyethylene ether, polyoxyethylene monomethyl ether, polyoxypropylene monomethyl ether, and polyoxyethylene polyoxypropylene monomethyl ether. , polyoxyethylene monoethyl ether, polyoxypropylene monoethyl ether, polyoxyethylene polyoxypropylene monoethyl ether and other glycol ‧ esters, phthalic acid esters such as diethyl phthalate, o-toluenesulfonamide, Toluene sulfonamide, tributyl citrate, triethyl citrate, ethyl triethyl citrate, tri-n-propyl citrate, tri-n-butyl citrate.

The amount in the case of containing a plasticizer is preferably from 5 to 50% by mass, more preferably from 5 to 30% by mass, based on the photosensitive resin composition. From the viewpoint of suppressing the development time, it is preferably 5% by mass or more from the viewpoint of imparting flexibility to the cured film, and is preferably 50% by mass or less from the viewpoint of suppressing insufficient hardening or cold flow.

<Photosensitive Resin Composition Blending Liquid>

The photosensitive resin composition of this invention can be prepared as the photosensitive resin composition preparation liquid which added the solvent. As a suitable solvent, a ketone represented by methyl ethyl ketone (MEK), or an alcohol such as methanol, ethanol or isopropyl alcohol can be mentioned. It is preferred to add a solvent to the photosensitive resin composition so that the viscosity of the photosensitive resin composition preparation liquid becomes 500 to 4,000 mPa·sec at 25 °C.

<Photosensitive Resin Laminate>

The photosensitive resin laminate of the present invention contains a photosensitive resin layer and a support for supporting the layer, and may have a protective layer on the surface opposite to the support of the photosensitive resin layer, as needed.

As the support used herein, a transparent one that penetrates light emitted from the exposure light source is preferable. Examples of such a support include a polyethylene terephthalate film, a polyvinyl alcohol film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyvinylidene chloride film, a vinylidene chloride copolymer film, and the like. A polymethyl methacrylate copolymer film, a polystyrene film, a polyacrylonitrile film, a styrene copolymer film, a polyamide film, a cellulose derivative film, or the like. These films may also be used as extensions as needed. It is preferred that the haze (haze) is 5 or less. Although the thickness of the film is advantageous in terms of image formation property and economy, it is preferable to use 10 to 30 μm because it is necessary to maintain strength and the like.

Moreover, the important characteristic of the protective layer used for the photosensitive resin laminated body is that the protective layer is sufficiently smaller than the support for the adhesion to the photosensitive resin layer, and can be easily peeled off. For example, a polyethylene film, a polypropylene film or the like can be preferably used as the protective layer. Further, a film excellent in peelability disclosed in Japanese Laid-Open Patent Publication No. SHO 59-202457 can be used. The film thickness of the protective layer is preferably from 10 to 100 μm, more preferably from 10 to 50 μm.

The thickness of the photosensitive resin layer in the photosensitive resin laminate of the present invention is preferably 5 to 100 μm, more preferably 5 to 50 μm. The thinner the thickness, the higher the resolution, and the thicker the film strength, the more suitable it can be selected depending on the application.

The method of producing the photosensitive resin laminate of the present invention by sequentially laminating the support, the photosensitive resin layer, and optionally the protective layer can be carried out by a conventionally known method. For example, the photosensitive resin composition used in the photosensitive resin layer is prepared as the photosensitive resin composition preparation liquid, and is first applied to a support by a bar coater or a roll coater, and dried. A photosensitive resin layer containing the photosensitive resin composition is laminated on a support. Then, if necessary, a protective layer is laminated on the photosensitive resin layer, whereby a photosensitive resin laminate can be produced.

<Photoresist pattern forming method>

The photoresist pattern using the photosensitive resin laminate of the present invention can be formed by a step including a lamination step, an exposure step, and a development step. An example of a specific method is disclosed.

First, a lamination step is performed using a laminator. In the case where the photosensitive resin laminate has a protective layer, after the protective layer is peeled off, the photosensitive resin layer is heated and pressure-bonded to the surface of the substrate by a laminator to be laminated. In this case, the photosensitive resin layer may be laminated only on one surface of the substrate surface, and may be laminated on both sides as needed. The heating temperature at this time is usually 40 to 160 °C. Further, by performing the thermocompression bonding twice or more, the adhesion of the obtained photoresist pattern to the substrate can be improved. In this case, the two-stage laminating machine having a double roll may be used for the crimping, or may be crimped by the roller several times.

Next, the exposure step is performed using an exposure machine. If necessary, the release support is exposed through the photomask by active light. The amount of exposure is determined by the illumination of the light source and the exposure time. It can be measured using a light meter.

In the exposure step, a maskless exposure method can be used. The maskless exposure is directly exposed on the substrate by the drawing device without using a mask. As the light source, a semiconductor laser or an ultrahigh pressure mercury lamp having a wavelength of 350 to 410 nm is used. The drawing pattern is controlled by a computer, and the amount of exposure in this case is determined according to the illuminance of the exposure light source and the moving speed of the substrate.

Next, the developing step is carried out using a developing device. After the exposure, when the support is provided on the photosensitive resin layer, it is removed. Then, the unexposed portion was developed by using a developing solution containing an alkaline aqueous solution to obtain a resist image. As the alkaline aqueous solution, an aqueous solution of Na ₂ CO ₃ or K ₂ CO ₃ is preferred. These are selected in accordance with the characteristics of the photosensitive resin layer, and are usually a Na ₂ CO ₃ aqueous solution having a concentration of 0.2 to 2% by mass. In the alkaline aqueous solution, a surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like may be mixed. Further, the temperature of the developer in the developing step is preferably maintained at a fixed temperature in the range of 20 to 40 °C.

The photoresist pattern is obtained by the above steps, but depending on the case, a heating step of 100 to 300 ° C may be further performed. By performing this heating step, the chemical resistance can be further improved. Heating can be performed by means of hot air, infrared rays, far infrared rays or the like.

<Manufacturing method of printed circuit board>

In the method for producing a printed wiring board according to the present invention, the photoresist pattern is formed on the copper foil laminate or the flexible substrate as the substrate by the photoresist pattern forming method, and then the film is formed through the following steps.

First, a step of forming a conductor pattern by a known method such as an etching method or a plating method on a copper surface of a substrate exposed by development is performed.

Thereafter, a peeling step of peeling the photoresist pattern from the substrate by an aqueous solution having a stronger alkalinity than the developer is performed to obtain a desired printed circuit board. The alkaline aqueous solution for peeling (hereinafter also referred to as "peeling liquid") is not particularly limited, and an aqueous solution of NaOH or KOH having a concentration of 2 to 5% by mass is usually used. A small amount of a water-soluble solvent may also be added to the stripping solution. Further, the temperature of the stripping liquid in the stripping step is preferably in the range of 40 to 70 °C.

<Method of manufacturing lead frame>

In the method of manufacturing a lead frame of the present invention, a photoresist pattern is formed on a metal plate such as copper, a copper alloy or an iron-based alloy as a substrate by the above-described photoresist pattern forming method, and then the film is formed through the following steps.

First, a step of etching a substrate exposed by development to form a conductor pattern is performed. Thereafter, a peeling step of peeling the photoresist pattern by the same method as the above-described method of manufacturing a printed circuit board is performed to obtain a desired lead frame.

<Method of Manufacturing Semiconductor Package>

In the method of manufacturing a semiconductor package of the present invention, a wafer after completion of circuit formation as an LSI is packaged by the following steps, thereby manufacturing a semiconductor package.

First, copper sulfate plating is performed on a portion of the base material of the substrate to which the photoresist pattern obtained by development is exposed, and a conductor pattern is formed. Thereafter, a peeling step of peeling off the photoresist pattern by the same method as the method of manufacturing the printed wiring board is performed, and further, etching is performed on a portion other than the columnar plating to remove the thin metal layer, and the above-described etching is performed. The wafer is obtained to obtain the desired semiconductor package.

<Method of manufacturing bumps>

The manufacturing method of the bump of the present invention is performed by encapsulating a wafer after completion of circuit formation as an LSI, and bumps are produced by the following steps.

First, copper sulfate plating is performed on a portion of the base material of the substrate to which the photoresist pattern obtained by development is exposed, and a conductor pattern is formed. Thereafter, a peeling step of peeling off the photoresist pattern by the same method as the method of manufacturing the printed wiring board is performed, and further, a step of removing a thin metal layer other than plating by etching is performed. This achieves the desired bumps.

<Method of Manufacturing Substrate Having Concavo-Concave Pattern>

According to the above-described photoresist pattern forming method, the photoresist pattern can be used as a protective cover member when the substrate is processed by a sand blast method.

Examples of the substrate include glass, tantalum wafer, amorphous germanium, polycrystalline germanium, ceramics, sapphire, and metal materials. A photoresist pattern is formed on the substrate such as glass by the same method as the above-described photoresist pattern forming method. Thereafter, a step of blasting the target to a depth by spraying the spray from the formed photoresist pattern, and a step of removing the photoresist pattern remaining on the substrate from the substrate by an alkaline stripping solution or the like may be performed. A substrate having a fine concavo-convex pattern on a substrate. The spray used in the above blasting step is known, and for example, fine particles of about 2 to 100 μm such as SiC, SiO ₂ , Al ₂ O ₃ , CaCO ₃ , ZrO, glass, or stainless steel are used.

The method for producing a substrate having a concave-convex pattern by the sandblasting method can be used for the production of a separator for a flat panel display, the glass lid processing for an organic EL, the opening of a silicon wafer, and the pin processing of a ceramic. Further, it can be used for the production of a ferroelectric film and an electrode of a metal material layer selected from the group consisting of a noble metal, a noble metal alloy, a high melting point metal, and a high melting point metal compound.

[Examples]

Hereinafter, an example of an embodiment of the present invention will be specifically described.

(Examples 1 to 3, Reference Example 4, Comparative Examples 1 to 5)

First, the preparation methods of the samples for evaluation of the examples, the reference examples, and the comparative examples will be described. Next, the evaluation methods of the obtained samples and the evaluation results thereof will be disclosed.

1. Production of evaluation samples

The samples for evaluation in the examples, the reference examples, and the comparative examples were produced as follows.

<Production of Photosensitive Resin Laminate>

The photosensitive resin composition and the solvent of the composition shown in the following Table 1 (wherein the number of each component is expressed as a solid content (parts by mass)) are sufficiently stirred and mixed to prepare a photosensitive resin composition preparation liquid. The surface of a 16 μm-thick polyethylene terephthalate film as a support was uniformly coated by a bar coater, and dried in a dryer at 95 ° C for 2.5 minutes to form a photosensitive resin layer. The thickness of the photosensitive resin layer was 25 μm.

Then, a 21 μm thick polyethylene film of the protective layer was bonded to the surface of the uncovered polyethylene terephthalate film of the photosensitive resin layer to obtain a photosensitive resin laminate.

The names of the material components B-1 to D-2 in the photosensitive resin composition preparation liquid indicated by the abbreviation in Table 1 are disclosed in Table 2 below.

<substrate surface>

As a substrate for evaluation of the degree of evaluation, a substrate for evaluation of the contact angle, and a substrate for evaluation of the modulus of elasticity, a surface of a 0.4 mm thick copper foil laminate having a 35 μm rolled copper foil laminated thereon was prepared by subjecting (A) a spray pressure of 0.20 MPa to a sandblasting brush. Grinding (manufactured by Carlit, Japan, Sakurundum R (registered trademark) #220).

<layer>

The polyethylene foil film of the photosensitive resin laminate was peeled off from the entire surface and heated to 60 ° C on a copper foil laminate using a heating roll laminator (Asahi Kasei Electronics Co., Ltd., AL-70). The photosensitive resin laminate was laminated at a roll temperature of 105 °C. The gas pressure is 0.35 MPa and the lamination speed is 1.5 m/min.

<exposure>

The substrate for the evaluation of the resolution was exposed using a chrome glass mask and an ultrahigh pressure mercury lamp (manufactured by ORC MANUFACTURING, HMW-201 KB). The contact angle evaluation substrate and the elastic modulus evaluation substrate were exposed without using a photomask.

<development>

After the polyethylene terephthalate film was peeled off, a 1% by mass aqueous Na ₂ CO ₃ solution at 30° C. was sprayed at a specific time to dissolve and remove the unexposed portion of the photosensitive resin layer. At this time, the minimum time required to completely dissolve the photosensitive resin layer of the unexposed portion is set as the minimum development time.

2. Evaluation method

Each evaluation method is as follows.

(1) Resolution

The substrate for the evaluation of the resolution after 15 minutes of lamination was exposed to a line mask (chrome glass mask) having a ratio of the width of the exposed portion to the unexposed portion of 1:1. The development is performed at twice the development time of the minimum development time, and the minimum mask line width normally formed by the hardened photoresist line is taken as the value of the resolution, and the classification is performed as follows:

◎: the resolution is 8 μm or less;

○: the resolution value exceeds 8 μm and is 10 μm or less;

×: The resolution value exceeds 10 μm.

(2) Adhesion

The substrate for the evaluation of the resolution after 15 minutes of lamination was exposed by a pattern mask (chrome glass mask) including individual lines of various widths. The development is performed at twice the development time of the minimum development time, and the minimum mask line width normally formed by the hardened photoresist line is used as the value of the adhesion, and the classification is performed as follows:

○: the value of the adhesion is 10 μm or less;

×: The value of the adhesion is more than 10 μm.

(3) Contact angle

The substrate for the evaluation of the resolution after 15 minutes of lamination was exposed without using a photomask. The exposure was performed with the exposure amount of the minimum resolution at the time of resolution evaluation. The development was carried out at twice the development time of the minimum development time to obtain a substrate for measurement of the contact angle, and the contact angle was measured.

(4) Young's modulus

The substrate for the evaluation of the resolution after 15 minutes of lamination was exposed without using a photomask. The exposure was performed with the exposure amount of the minimum resolution at the time of resolution evaluation. The development was carried out at twice the development time of the minimum development time to obtain a substrate for Young's modulus measurement, and the Young's modulus (modulus of elasticity) was measured.

The evaluation results of Examples 1 to 3, Reference Example 4, and Comparative Examples 1 to 5 are shown in Table 1 below.

[Table 2]

As is apparent from Table 1, in Examples 1 to 3, both the contact angle and the elastic modulus were within the range of the present invention, whereby the resolution and the adhesion were excellent.

In Comparative Examples 1 to 5, it was found that the water contact angle and Young's modulus were outside the range of the present invention depending on the selection of the resin for the binder polymer and the photopolymerizable compound, and the ratio of the blending ratios, and the resolution was obtained. Or the adhesion is not excellent.

[Industrial availability]

The present invention can be used for manufacturing printed circuit boards, manufacturing of lead frames for IC chip mounting, precision processing of metal foils such as metal mask manufacturing, fabrication of packages such as BGA and CSP, fabrication of tape substrates such as COF or TAB, and semiconductor bumps. The manufacture of a separator for a flat panel display such as an ITO electrode or an address electrode or an electromagnetic wave mask, and a method of producing a substrate having a concavo-convex pattern by a sand blast method.

Claims (13)

A photosensitive resin composition comprising (A) a binder polymer: 20 to 90% by weight, (B) a photopolymerizable compound: 5 to 75% by weight, and (C) photopolymerization initiation The agent (A) binder polymer has one polymer in the molecule and one molecule in the molecule by using a carboxylic acid or a carboxylic acid anhydride having one polymerizable unsaturated group in the molecule. a copolymer having a weight average molecular weight of 5,000 to 100,000 obtained by copolymerization of a non-acidic second monomer, wherein the (B) photopolymerizable compound has at least one terminal ethylenically unsaturated group in the molecule. Addition of a polymerizable monomer; exposure of the above-mentioned photosensitive resin composition to a exposure amount of 5 stages of a 21-step Swarf stage exposure meter, followed by use of a 1% by mass aqueous sodium carbonate solution (30 ° C) for a minimum development time The water contact angle of the photosensitive resin layer obtained after the development of the time is more than 60°, and the Young's modulus is 2.5 GPa or more and less than 4 GPa; and the ethylenically unsaturated bond concentration of the photosensitive resin composition is 0.01 mol / 100 g ~ 0.1 mol / 100g. The photosensitive resin composition of claim 1, wherein the (A) binder polymer is a phenyl group-containing copolymer or a cyclohexyl group-containing copolymer. The photosensitive resin composition of claim 1, wherein the photosensitive resin layer has a Young's modulus of 3 GPa or more and less than 4 GPa. The photosensitive resin composition of claim 1, wherein the (C) photopolymerizable initiator contains a 2,4,5-triarylimidazole dimer. A photosensitive resin laminate which is obtained by laminating a photosensitive resin composition according to any one of claims 1 to 4 on a support. A method of forming a photoresist pattern comprising a layer forming step, an exposure step, and a developing step of forming a layer of the photosensitive resin composition according to any one of claims 1 to 4 on a substrate. The method of claim 6, wherein in the exposing step, the photosensitive resin layer is directly drawn using a photosensitive resin composition and then exposed. A method of manufacturing a printed circuit board comprising the step of etching or plating a substrate on which a photoresist pattern is formed by a method of forming a photoresist pattern of claim 6. A method for producing a substrate having a concave-convex pattern, comprising the step of processing a substrate having a photoresist pattern formed by the method for forming a photoresist pattern of claim 6 by sand blasting. A method of manufacturing a semiconductor package or a bump, comprising the step of etching or plating a substrate on which a photoresist pattern is formed by a method of forming a photoresist pattern of claim 6. A method of manufacturing a lead frame, comprising the step of etching or plating a substrate on which a photoresist pattern is formed by a method of forming a photoresist pattern of claim 6. A cured resin obtained by curing the photosensitive resin composition according to any one of claims 1 to 4. A resin cured product laminate which is provided with a cured resin of claim 12 on a support.