JP5444749B2 - Positive photosensitive resin composition, method for producing resist pattern, and electronic component - Google Patents

Description

  The present invention relates to a positive photosensitive resin composition, a resist pattern manufacturing method, and an electronic component.

  In recent years, as semiconductor devices have been highly integrated and increased in size, there has been a demand for thinner and smaller sealing resin packages. Furthermore, materials having superior electrical characteristics, heat resistance, mechanical characteristics, and the like are required for the surface protective film and interlayer insulating film of semiconductor elements and the rewiring layer of semiconductor packages. Polyimide resin is one of materials having such characteristics. Recently, studies have been made on photosensitive polyimides obtained by imparting photosensitive characteristics to polyimide resins themselves. If photosensitive polyimide is used, a resist pattern formation process can be simplified and a complicated manufacturing process can be shortened (for example, refer patent documents 1 and 2).

  The photosensitive polyimide film is formed by thinning a polyimide precursor (polyamic acid) solution (so-called varnish) obtained by reacting tetracarboxylic dianhydride and diamine with spin coating, etc., and thermally dehydrating and ring-closing (so-called curing) ) (See, for example, Non-Patent Document 1).

  On the other hand, a technique for imparting photosensitivity to a polymer such as polyimide that does not require dehydration ring closure to form a resist pattern having high heat resistance and high mechanical properties has been studied. For example, Non-Patent Document 2 and Patent Documents 3 to 6 discuss alicyclic polymers. In addition, a phenol resin having relatively excellent heat resistance, electrical insulation, and mechanical properties has been studied (for example, Patent Document 7).

JP-A-49-115541 JP 59-108031 A International Publication No. 2004/006020 Pamphlet JP 2006-106214 A JP 2004-2754 A JP 2003-368530 A Japanese Patent No. 3812654

Japan Polyimide Study Group "Latest Polyimides-Fundamentals and Applications" (2002) J. et al. Photopolym. Sci. Technol. 2005, Volume 18, p. 321-325

  However, although the conventional photosensitive polyimide has good adhesion and thermal shock resistance of the resist pattern to be formed, volume shrinkage due to dehydration ring closure (imidization) occurs during curing. There was a problem that loss and dimensional accuracy were reduced. In addition, conventional photosensitive resin compositions that can be developed with an alkaline aqueous solution using a polymer that does not require dehydration and ring closure require further improvements in photosensitive characteristics in terms of sensitivity, resolution, and generation of residues after development. Furthermore, the level of adhesion and thermal shock resistance of the resist pattern to be formed are not always satisfactory.

  Therefore, the present invention has a positive photosensitive property, can be developed with an aqueous alkaline solution, has a sufficiently small shrinkage due to curing, and has a resist pattern formed with excellent adhesion and thermal shock resistance. It aims at providing a type photosensitive resin composition. Another object of the present invention is to provide a resist pattern manufacturing method using the positive photosensitive resin composition and an electronic component having the resist pattern formed by the method.

  The positive photosensitive resin composition according to the present invention comprises (A) a polybasic acid anhydride-modified phenol resin obtained by reacting a phenolic hydroxyl group of a phenol resin with a polybasic acid anhydride, and (B) an acid by light. And (C) a thermal crosslinking agent, and (D) a solvent.

  By combining the specific components described above, the positive photosensitive resin composition according to the present invention has excellent photosensitive characteristics, can be developed with an alkaline aqueous solution, and shrinkage due to curing is sufficiently small. The formed resist pattern has excellent adhesion and thermal shock resistance.

  The phenol resin with which the polybasic acid anhydride is reacted is preferably modified with a drying oil or rubbery polymer.

  The component (A) preferably has a divalent group represented by the following general formula (I) in the molecule. In the formula (I), R represents a polycarboxylic anhydride residue.

  (A) It is preferable that the acid value of a component is 30-200 mgKOH / g.

  The component (B) is preferably an o-quinonediazide compound.

  The positive photosensitive resin composition according to the present invention preferably further contains (E) an elastomer.

  The positive photosensitive resin composition according to the present invention preferably contains 3 to 100 parts by mass of the (B) component with respect to 100 parts by mass of the (A) component. Moreover, it is preferable that the positive photosensitive resin composition which concerns on this invention contains 1-50 mass parts of (C) component with respect to 100 mass parts of (A) component.

  The method for producing a resist pattern according to the present invention comprises applying the positive photosensitive resin composition according to the present invention on a support substrate, drying the applied positive photosensitive resin composition, and forming a photosensitive resin film. A step of forming, a step of exposing the photosensitive resin film, a step of developing the exposed photosensitive resin film with an alkaline aqueous solution to form a resist pattern, and a step of heating the resist pattern.

  According to the production method of the present invention, a resist pattern having excellent adhesion and thermal shock resistance can be formed.

  The manufacturing method according to the present invention preferably includes a step of heating the resist pattern at 200 ° C. or lower. By heating the resist pattern at such a low temperature, damage to the device can be avoided and a highly reliable electronic component can be obtained. In addition, since the device is less damaged, a high yield can be obtained.

  In another aspect, the present invention relates to an electronic component. The electronic component according to the present invention may have a resist pattern manufactured by the manufacturing method according to the present invention as an interlayer insulating film layer or a surface protective film. The electronic component according to the present invention may have a resist pattern manufactured by the method for manufacturing a resist pattern according to the present invention as a cover coat layer. The electronic component according to the present invention may have a resist pattern manufactured by the method for manufacturing a resist pattern according to the present invention as a core for the rewiring layer. The electronic component according to the present invention may have a resist pattern manufactured by the method for manufacturing a resist pattern according to the present invention as a collar for holding conductive balls as external connection terminals. The electronic component according to the present invention may have a resist pattern manufactured by the method for manufacturing a resist pattern according to the present invention as an underfill. The electronic component according to the present invention may have a resist pattern manufactured by the method for manufacturing a resist pattern according to the present invention as a surface protective layer and / or a cover coat layer for the rewiring layer.

  According to the present invention, a positive resist film having excellent photosensitivity, developable with an alkaline aqueous solution, sufficiently small in shrinkage due to curing, and having excellent adhesion and thermal shock resistance in the formed resist pattern. Type photosensitive resin composition is provided. More specifically with respect to the photosensitive properties, the positive photosensitive resin composition according to the present invention is particularly excellent in terms of sensitivity, resolution, and residue control after development. Moreover, the heat resistance and flexibility (flexibility) of the formed cured film are also good. Furthermore, since the positive photosensitive resin composition of the present invention is soluble in an alkaline aqueous solution, it can form a resist pattern at low cost and has a low load on the global environment.

  According to the method for producing a resist pattern according to the present invention, even when the curing temperature is low (for example, 200 ° C. or less), the sensitivity, resolution, and adhesiveness are excellent, and the physical properties such as heat resistance are excellent. A resist pattern having a shape can be obtained. In the case of polyimide, imidization is incomplete when cured at a low temperature, so that the cured film is brittle and physical properties are lowered. In this respect, the present invention is advantageous compared to the polyimide method. Moreover, since the positive photosensitive resin composition of the present invention has a small volume shrinkage upon curing, a resist pattern having excellent dimensional stability can be obtained.

  The electronic component according to the present invention has a resist pattern excellent in shape, adhesion, and heat resistance, and further, the resist pattern is formed by curing at a low temperature, so that damage to the device can be avoided and reliability is ensured. It is a highly electronic component. Further, since the damage to the device is small, it can be manufactured with a high yield. Since the positive photosensitive resin composition of the present invention is excellent in stress relaxation property, adhesiveness and the like, it can also be used as various structural materials in variously developed packages having various structures. Furthermore, since the glass transition temperature of the cured film obtained by curing the film of the positive photosensitive resin composition is high, it can withstand a heating process such as sealing or solder reflow when mounting an electronic component having the cured film. There is an effect.

It is a schematic sectional drawing explaining one Embodiment of the manufacturing process of a semiconductor device. It is a schematic sectional drawing explaining one Embodiment of the manufacturing process of a semiconductor device. It is a schematic sectional drawing explaining one Embodiment of the manufacturing process of a semiconductor device. It is a schematic sectional drawing explaining one Embodiment of the manufacturing process of a semiconductor device. It is a schematic sectional drawing explaining one Embodiment of the manufacturing process of a semiconductor device. It is a schematic sectional drawing which shows one Embodiment of an electronic component (semiconductor device). It is a schematic sectional drawing which shows one Embodiment of an electronic component (semiconductor device).

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

  The positive photosensitive resin composition according to this embodiment includes (A) a polybasic acid anhydride-modified phenol resin, (B) a compound that generates an acid by light, (C) a thermal crosslinking agent, and (D). Contains a solvent.

  The polybasic acid anhydride-modified phenol resin is obtained by reacting a polybasic acid anhydride with the phenolic hydroxyl group of the phenol resin. The phenol resin is a polycondensation reaction product of phenol or a derivative thereof and aldehydes, and a typical example thereof is a novolak type phenol resin (novolak resin). Specific examples of novolak resins include phenol / formaldehyde novolak resins, cresol / formaldehyde novolak resins, xylylenol / formaldehyde novolak resins, resorcinol / formaldehyde novolak resins, and phenol-naphthol / formaldehyde novolak resins.

  Examples of the phenol derivative used for obtaining the phenol resin include o-cresol, m-cresol, p-cresol, o-ethylphenol, m-ethylphenol, p-ethylphenol, o-butylphenol, m-butylphenol, p-butylphenol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, 2,3,5-trimethylphenol and 3 Alkylphenols such as 4,4,5-trimethylphenol, alkoxyphenols such as methoxyphenol and 2-methoxy-4-methylphenol, alkenylphenols such as vinylphenol and allylphenol, aralkylphenols such as benzylphenol, metho Alkoxycarbonyl phenols such as sicarbonylphenol, arylcarbonylphenols such as benzoyloxyphenol, halogenated phenols such as chlorophenol, polyhydroxybenzenes such as catechol, resorcinol and pyrogallol, bisphenols such as bisphenol A and bisphenol F, and α- Alternatively, naphthol derivatives such as β-naphthol can be mentioned. A methylolated product of the above phenol derivative such as bishydroxymethyl-p-cresol may be used as the phenol derivative.

Other examples of phenol derivatives include p-hydroxyphenyl-2-ethanol, p-
Alcoholic properties such as hydroxyalkylphenols such as hydroxyphenyl-3-propanol and p-hydroxyphenyl-4-butanol, hydroxyalkylcresols such as hydroxyethylcresol, monoethylene oxide adducts of bisphenol, and monopropylene oxide adducts of bisphenol Hydroxyl-containing phenol derivative, p
Carboxyl group-containing phenol derivatives such as hydroxyphenylacetic acid, p-hydroxyphenylpropionic acid, p-hydroxyphenylbutanoic acid, p-hydroxycinnamic acid, hydroxybenzoic acid, hydroxyphenylbenzoic acid, hydroxyphenoxybenzoic acid and diphenolic acid Also mentioned.

  The above phenol derivatives are used alone or in combination of two or more.

  Examples of aldehydes used to obtain a phenol resin include formaldehyde, acetaldehyde, furfural, benzaldehyde, hydroxybenzaldehyde, methoxybenzaldehyde, hydroxyphenylacetaldehyde, methoxyphenylacetaldehyde, crotonaldehyde, chloroacetaldehyde, chlorophenylacetaldehyde, acetone and glycerin. Examples include aldehydes. Other examples of aldehydes include glyoxylic acid, methyl glyoxylate, phenyl glyoxylate, hydroxyphenyl glyoxylate, formylacetic acid, methyl formylacetate, 2-formylpropionic acid, methyl 2-formylpropionate, pyruvic acid, repric acid 4-acetylbutyric acid, acetone dicarboxylic acid, and 3,3′-4,4′-benzophenone tetracarboxylic acid. Formaldehyde precursors such as paraformaldehyde and trioxane may be used. These are used singly or in combination of two or more.

  Reaction of a phenol derivative and aldehydes is a polycondensation reaction, and can be performed on the synthesis conditions of a well-known phenol resin. In the reaction, it is desirable to use an acid catalyst. Examples of the acid catalyst include hydrochloric acid, sulfuric acid, formic acid, acetic acid, p-toluenesulfonic acid, and oxalic acid. These are used singly or in combination of two or more.

  In general, the reaction between the phenol derivative and the aldehyde is preferably performed at a temperature of 100 to 120 ° C. The reaction time varies depending on the type and amount of the catalyst used, but is usually 1 to 50 hours. After completion of the reaction, the reaction product is dehydrated under reduced pressure at a temperature of 200 ° C. or lower to obtain a phenol resin. As the reaction solvent, toluene, xylene, methanol and the like can be used.

  The phenol resin is preferably one modified with a drying oil or a rubber-like polymer (hereinafter sometimes referred to as “plasticized phenol resin”). A cured film of a positive photosensitive resin composition containing a polybasic acid anhydride-modified phenol resin obtained from a plasticized phenol resin is excellent in flexibility (flexibility).

The plasticized phenol resin can be obtained by a method (first method) in which the following (i) and (ii) are reacted.
(I) Compound (ii) Aldehydes obtained by reacting phenol or a derivative thereof with drying oil or rubbery polymer

  As the phenol derivative for obtaining the compound (i), the same compounds as those for obtaining the phenol resin can be used.

  The drying oil for obtaining the above compound (i) is an ester of glycerin and unsaturated fatty acid, and its iodine value is 130 or more. Specific examples of the drying oil include paulownia oil, linseed oil, soybean oil, walnut oil, safflower oil, sunflower oil, camellia oil and coconut oil. Processed drying oils obtained using these drying oils as raw materials may be used. Among the above-mentioned drying oils, tung oil, linseed oil, soybean oil, walnut oil, and safflower oil are preferable, and tung oil and linseed oil are more preferable from the viewpoint of more effectively and reliably achieving the above-described effects of the present invention. These drying oils are used alone or in combination of two or more.

  The rubbery polymer for obtaining the compound (i) is a polymer compound having a Tg of 20 ° C. or less and having a functional group that reacts with phenol or a derivative thereof or a phenol resin. The rubbery polymer may be natural rubber or synthetic rubber (elastomer).

  Specific examples of elastomers include olefin elastomer, styrene elastomer, nitrile rubber (poly (acrylonitrile-co-butadiene)), ethylene-propylene rubber (poly (ethylene-co-propylene)), acrylic elastomer, epichlorohydride. Rubber, silicone elastomer, fluorine rubber, urethane elastomer (urethane rubber), chlorosulfonated polyethylene, polyester elastomer and polyamide elastomer.

  Examples of styrenic elastomers include styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, styrene-ethylene-butylene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers, and styrene-butadiene-methacrylate blocks. Polymers. The styrenic elastomer may contain monomer units of styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene together with or in place of styrene.

  Commercially available styrenic elastomers include Tufprene, Solprene T, Asaprene T, Tuftec (above, Asahi Kasei Kogyo Co., Ltd.), Elastomer AR (Aron Kasei Co., Ltd.), Kraton G, Califlex (above, Shell Japan Ltd.) Manufactured), JSR-TR, TSR-SIS, Dynalon (above, manufactured by JSR), Denka STR (manufactured by Electrochemical Co., Ltd.), Quintac (manufactured by Nippon Zeon), TPE-SB series (manufactured by Sumitomo Chemical), Lavalon (Mitsubishi Chemical Co., Ltd.), Septon, Hybler (above, Kuraray Co., Ltd.), Sumiflex (Sumitomo Bakelite Co., Ltd.), Rheostomer, Actimer (above, Riken Vinyl Industry Co., Ltd.), and Paraloid EXL series (Rohm and Haas Co., Ltd.) )

  The olefin-based elastomer is a copolymer of an α-olefin having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene and 4-methyl-pentene. Specific examples of the olefin elastomer include ethylene-propylene copolymer (EPR) and ethylene-propylene-diene copolymer (EPDM). Olefin-based elastomers are copolymers and epoxidation of diene having 2 to 20 carbon atoms such as dicyclopentadiene, 1,4-hexadiene, cyclooctanediene, methylene norbornene, ethylidene norbornene, butadiene and isoprene, and α-olefin. It may be carboxy-modified NBR obtained by copolymerizing methacrylic acid with polybutadiene or butadiene-acrylonitrile copolymer. Other examples of olefin elastomers include ethylene-α-olefin copolymer rubber, ethylene-α-olefin-diene copolymer rubber, propylene-α-olefin copolymer rubber, butene-α-olefin copolymer. There are rubber, isoprene rubber (polyisoprene), butadiene rubber (polybutadiene), chloroprene rubber (polychloroprene) and butyl rubber (poly (butylene-co-butadiene)).

  Commercially available olefin-based elastomers include milastoma (manufactured by Mitsui Petrochemical), EXACT (manufactured by Exxon Chemical), ENGAGE (manufactured by Dow Chemical), Nipol series (manufactured by Nippon Zeon), hydrogenated styrene- Butadiene rubber DYNABON HSBR (manufactured by JSR), butadiene-acrylonitrile copolymer NBR series (manufactured by JSR), XER series of both end carboxyl group-modified butadiene-acrylonitrile copolymers having a crosslinking point (manufactured by JSR), polybutadiene Examples include partially epoxidized epoxidized polybudadiene BF-1000 (manufactured by Nippon Soda Co., Ltd.) and liquid butadiene-acrylonitrile copolymer HYCAR series (manufactured by Ube Industries).

  The urethane-based elastomer has a hard segment generated from a low molecular (short chain) diol and a diisocyanate, and a soft segment generated from a high molecular (long chain) diol and a diisocyanate. Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6 -Hexylene carbonate) and poly (1,6-hexylene-neopentylene adipate). The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000. Examples of the low molecular (short chain) diol include ethylene glycol, propylene glycol, 1,4-butanediol, and bisphenol A. The number average molecular weight of the short-chain diol is preferably 48 to 500.

  Commercially available urethane-based elastomers include PANDEX T-2185, T-2983N (manufactured by Dainippon Ink & Chemicals, Inc.), sylactolan E790, and the Hitaroid series (manufactured by Hitachi Chemical Co., Ltd.).

  A polyester elastomer is an elastomer having a hard segment and a soft segment, and is obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof. Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid and dodecanedicarboxylic acid, and cyclohexanedicarboxylic acid. And alicyclic dicarboxylic acids such as acids. The hydrogen atom of the aromatic ring of the aromatic dicarboxylic acid may be substituted with a methyl group, an ethyl group, a phenyl group, or the like. These compounds can be used alone or in combination of two or more. Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol. Or alicyclic diol, bisphenol A, bis- (4-hydroxyphenyl) -methane, bis- (4-hydroxy-3-methylphenyl) -propane, and resorcin. These compounds can be used alone or in combination of two or more. A multi-block copolymer having an aromatic polyester (eg, polybutylene terephthalate) portion as a hard segment and an aliphatic polyester (eg, polytetramethylene glycol) portion as a soft segment can be used.

  Polyester elastomers are available in various grades depending on the types and ratios of hard segments and soft segments, and the difference in molecular weight. Commercially available polyester elastomers include Hytrel (Du Pont-Toray), Perprene (Toyobo) and Espel (Hitachi Chemical Industries).

  The polyamide-based elastomer has a hard segment made of polyamide and a soft segment made of polyether or polyester. Polyamide elastomers are roughly classified into two types: polyether block amide type and polyether ester block amide type. Examples of the polyamide include polyamide 6, polyamide 11, and polyamide 12. Examples of the polyether include polyoxyethylene, polyoxypropylene, and polytetramethylene glycol.

  Commercially available polyamide-based elastomers include UBE polyamide elastomer (manufactured by Ube Industries), Daiamide (manufactured by Daicel Huls), PEBAX (manufactured by Toray Industries, Inc.), Grilon ELY (manufactured by MMS Japan), Novamid (Mitsubishi) Chemical) and Glare (Dainippon Ink Chemical Co., Ltd.).

  Acrylic elastomers are acrylic esters such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate and ethoxyethyl acrylate, monomers having an epoxy group such as glycidyl methacrylate and allyl glycidyl ether, and / or vinyls such as acrylonitrile and ethylene. It is obtained by copolymerizing with a monomer. Acrylic elastomers include acrylic rubbers (poly (acrylic ester-co-chloroethyl vinyl ether) and poly (acrylic ester-co-acrylonitrile). More specifically, acrylonitrile-butyl acrylate copolymer, acrylonitrile. -Butyl acrylate-ethyl acrylate copolymer and acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer.

  Silicone elastomers are elastomers containing organopolysiloxane as a main component, and are classified into polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. A part of the organopolysiloxane may be modified with a vinyl group, an alkoxy group or the like. Specific examples of the silicone elastomer include silicone rubber (poly (dimethylsiloxane) and poly (dimethylsiloxane-co-methylvinylsiloxane)).

  Commercially available silicone elastomers include the KE series (manufactured by Shin-Etsu Chemical Co., Ltd.), the SE series, the CY series, and the SH series (above, manufactured by Toray Dow Corning Silicone).

  In addition to the above elastomer, a rubber-modified epoxy resin can be used as the rubbery elastomer. The rubber-modified epoxy resin includes, for example, a part or all of epoxy groups such as bisphenol F type epoxy resin, bisphenol A type epoxy resin, salicylaldehyde type epoxy resin, phenol novolac type epoxy resin, or cresol novolac type epoxy resin, It can be obtained by modifying with a terminal carboxylic acid-modified butadiene-acrylonitrile rubber and a terminal amino-modified silicone rubber.

  The rubber-like polymer may be a fine particle elastomer (hereinafter also referred to as “elastomer fine particles”). The elastomer fine particles are dispersed in a fine particle state in the positive photosensitive resin composition. The elastomer fine particles may contain an elastomer that forms islands in a sea-island structure by phase separation in an incompatible system, or an elastomer that forms so-called microdomains.

  Elastomer particles are a copolymer of a crosslinkable monomer having two or more unsaturated polymerizable groups and one or more other monomers selected so that the Tg of the elastomer particles is 20 ° C. or less (so-called crosslinked particles). Is preferred. The other monomer may have a functional group other than the polymerizable group, for example, a functional group such as a carboxyl group, an epoxy group, an amino group, an isocyanato group, or a hydroxyl group.

  Examples of crosslinkable monomers include divinylbenzene, diallyl phthalate, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, polyethylene glycol di (Meth) acrylate and polypropylene glycol di (meth) acrylate may be mentioned. Of these, divinylbenzene is preferred.

  In producing the elastomer fine particles, a crosslinkable monomer is used in an amount in the range of 1 to 20% by weight, more preferably in the range of 2 to 10% by weight, based on all monomers used for copolymerization.

  Examples of other monomers include diene compounds such as butadiene, isoprene, dimethylbutadiene, chloroprene and 1,3-pentadiene, (meth) acrylonitrile, α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-methoxyacrylonitrile, α- Unsaturated nitrile compounds such as ethoxyacrylonitrile, crotonic acid nitrile, cinnamic acid nitrile, itaconic acid dinitrile, maleic acid dinitrile and fumaric acid dinitrile, (meth) acrylamide, N, N′-methylenebis (meth) acrylamide, N, N '-Ethylenebis (meth) acrylamide, N, N'-hexamethylenebis (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylic , N, N-bis (2-hydroxyethyl) (meth) acrylamide, unsaturated amides such as crotonic acid amide and cinnamic acid amide, methyl (meth) acrylate, ethyl (meth) acrylate, (meth) (Meth) acrylic acid esters such as propyl acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, lauryl (meth) acrylate, polyethylene glycol (meth) acrylate and polypropylene glycol (meth) acrylate, styrene, Aromatic vinyl compounds such as α-methylstyrene, o-methoxystyrene, p-hydroxystyrene and p-isopropenylphenol, diglycidyl ether of bisphenol A and diglycidyl ether of glycol, (meth) acrylic acid and hydroxyalkyl ( Meta) Epoxy (meth) acrylate obtained by reaction with acrylate, urethane (meth) acrylate obtained by reaction of hydroxyalkyl (meth) acrylate and polyisocyanate, glycidyl (meth) acrylate, (meth) allyl glycidyl ether, etc. Epoxy group-containing unsaturated compounds, (meth) acrylic acid, itaconic acid, succinic acid-β- (meth) acryloxyethyl, maleic acid-β- (meth) acryloxyethyl, phthalic acid-β- (meth) acrylic Unsaturated acid compounds such as loxyethyl and hexahydrophthalic acid-β- (meth) acryloxyethyl, amino group-containing unsaturated compounds such as dimethylamino (meth) acrylate and diethylamino (meth) acrylate, (meth) acrylamide and dimethyl (Meta) Acry Examples include amide group-containing unsaturated compounds such as luamide, and hydroxyl-containing unsaturated compounds such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate.

  Among these, butadiene, isoprene, (meth) acrylonitrile, (meth) acrylic acid alkyl esters, styrene, p-hydroxystyrene, p-isopropenylphenol, glycidyl (meth) acrylate, (meth) acrylic acid and hydroxyalkyl ( Particularly preferred are (meth) acrylates.

  As the other monomer, it is preferable to use at least one diene compound, specifically, butadiene. Such a diene compound is desirably used in an amount of 20 to 80% by weight, preferably 30 to 70% by weight, based on all monomers used for copolymerization. When the diene compound is copolymerized in the amount as described above with respect to all monomers, soft fine particles are formed. Thereby, it can prevent especially that a crack (crack) arises in a cured film, and can obtain the cured film excellent in durability.

  The average particle diameter of the elastomer fine particles is usually about 30 to 500 nm. The average particle diameter of the elastomer fine particles is preferably 40 to 200 nm, more preferably 50 to 120 nm.

  The method of controlling the particle size of the elastomer fine particles is not particularly limited, but when the elastomer fine particles are synthesized by emulsion polymerization, the number of micelles during the emulsion polymerization is controlled by the amount of the emulsifier used to control the particle size. The method of doing can be illustrated.

  Among the rubber-like polymers mentioned above, it is more preferable to modify the phenol resin using a rubber-like polymer having a carbon-carbon double bond because the plasticized phenol resin is excellent in toughness and flexibility. Specifically, natural rubber, isoprene rubber (polyisoprene), butadiene rubber (polybutadiene), chloroprene rubber (polychloroprene), butyl rubber (poly (butylene-co-butadiene)), styrene-butadiene rubber (poly (styrene-co) -Butadiene)), nitrile rubber (poly (acrylonitrile-co-butadiene)), poly (dimethylsiloxane-co-methylvinylsiloxane)), styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-butadiene -C2-C2 such as methacrylate block polymer, dicyclopentadiene, 1,4-hexadiene, cyclooctanediene, methylene norbornene, ethylidene norbornene, butadiene, isoprene, etc. Of dienes and α-olefin, carboxy-modified NBR obtained by copolymerizing butadiene-acrylonitrile copolymer with methacrylic acid, ethylene-α-olefin-diene copolymer rubber, hydrogenated styrene-butadiene rubber (DYNABON) A rubbery polymer selected from HSBR (manufactured by JSR)) and a rubber-modified epoxy resin and having a carbon-carbon double bond is preferable. These rubber-like polymers are used alone or in combination of two or more.

  As the aldehydes of (ii) described above, those similar to the synthesis of phenol resin can be used.

  The reaction of phenol or a derivative thereof with a drying oil or rubbery polymer is usually preferably performed at 50 to 130 ° C. From the viewpoint of improving the flexibility of the cured film, the reaction ratio of phenol or a derivative thereof to drying oil or a rubber-like polymer is 1 to 100 masses of the drying oil or rubber-like polymer with respect to 100 parts by mass of phenol or a derivative thereof. Part is preferable, and 5 to 50 parts by mass is more preferable. When the reaction ratio of the drying oil or rubbery polymer is less than 1 part by mass, the flexibility of the cured film tends to be lowered. On the other hand, when the reaction ratio of the drying oil or rubbery polymer exceeds 100 parts by mass, the heat resistance of the cured film tends to decrease. In the reaction, if necessary, p-toluenesulfonic acid, trifluoromethanesulfonic acid or the like may be used as a catalyst.

  The reaction between the compound (i) and the aldehyde (ii) is a polycondensation reaction and can be carried out under known phenol resin synthesis conditions. In the reaction, it is desirable to use an acid catalyst. Examples of the acidic catalyst include hydrochloric acid, sulfuric acid, formic acid, acetic acid, p-toluenesulfonic acid, and oxalic acid. These are used singly or in combination of two or more.

  In general, the above reaction is preferably performed at a temperature of 100 to 120 ° C. Moreover, although reaction time changes with kinds and quantity of the catalyst to be used, it is 1 to 50 hours normally. After completion of the reaction, the reaction product is dehydrated under reduced pressure at a temperature of 200 ° C. or lower to obtain a product (plasticized phenol resin). In addition, solvents, such as toluene, xylene, and methanol, can be used for reaction.

  A compound other than phenol such as m-xylene may be polycondensed with (ii) aldehydes together with the compound of (i). In this case, the molar ratio of the compound other than phenol to the compound obtained by reacting (i) a phenol derivative with a drying oil or rubbery polymer is preferably less than 0.5.

  The plasticized phenol resin can also be obtained by a method (second method) in which a phenol resin is reacted with a drying oil or a rubbery polymer. The same phenol resin as that described above is used. As the drying oil and the rubbery polymer, those similar to the first method are used.

  The polybasic acid anhydride to be reacted with the phenol resin is a compound obtained by dehydrating and condensing the carboxylic acid of a polybasic acid having a plurality of carboxyl groups to form an acid anhydride group. Examples of the polybasic acid anhydride include phthalic anhydride, succinic anhydride, octenyl succinic anhydride, pentadodecenyl succinic anhydride, maleic anhydride, itaconic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride Dibasic acid anhydrides such as methylhexahydrophthalic anhydride, nadic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride and tetrabromophthalic anhydride, trimellitic anhydride, biphenyltetra Carboxylic dianhydride, naphthalene tetracarboxylic dianhydride, diphenyl ether tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, cyclopentane tetracarboxylic dianhydride, pyromellitic anhydride and benzophenone tetra Aliphatic or aromatic tetrabasic acid dianhydride, such as carboxylic acid dianhydride. You may use these individually by 1 type or in combination of 2 or more types.

  Of these, dibasic acid anhydrides are preferred. Specifically, it is preferably at least one selected from the group consisting of tetrahydrophthalic anhydride, succinic anhydride, and hexahydrophthalic anhydride. In this case, there is an advantage that a resist pattern having a good shape can be easily obtained.

  The reaction between the phenol resin and the polybasic acid anhydride is preferably performed at 50 to 130 ° C. It is preferable to react 0.10-0.80 mol of polybasic acid anhydride with respect to 1 mol of phenolic hydroxyl groups, more preferably 0.15-0.60 mol, more preferably 0.20-0. More preferably, 40 moles are reacted. When the ratio of the polybasic acid anhydride is less than 0.10 mol, the developability tends to be lower than in the above range, and the ratio of the polybasic acid anhydride exceeds 0.80 mol. And compared with the case where it exists in the said range, it exists in the tendency for the alkali resistance of an unexposed part to fall.

  You may perform the said reaction in presence of a catalyst as needed. In this case, the reaction can be performed quickly. Examples of such catalysts include tertiary amines such as triethylamine, quaternary ammonium salts such as triethylbenzylammonium chloride, imidazole compounds such as 2-ethyl-4-methylimidazole, and phosphorus compounds such as triphenylphosphine.

  The polybasic acid anhydride-modified phenol resin preferably has at least one divalent group represented by the above general formula (I) in the molecule. Thereby, the solubility with respect to the developing solution of a positive photosensitive resin composition and a development characteristic become especially excellent.

  The divalent group of the formula (I) is usually introduced into the polybasic acid anhydride-modified phenol resin by a reaction between a phenolic hydroxyl group and a dibasic acid anhydride. In the formula (I), R is a dibasic acid anhydride residue derived from the dibasic acid anhydride used to obtain the polybasic acid anhydride-modified phenol resin (excluding the carboxyl group from the dibasic acid anhydride). Part). Dibasic acid anhydrides include phthalic anhydride, succinic anhydride, octenyl succinic anhydride, pentadodecenyl succinic anhydride, maleic anhydride, itaconic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, There are methylhexahydrophthalic anhydride, nadic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, tetrabromophthalic anhydride and trimellitic anhydride.

  The acid value of the polybasic acid anhydride-modified phenol resin is preferably 30 to 200 mgKOH / g, more preferably 40 to 170 mgKOH / g, and still more preferably 50 to 150 mgKOH / g. When the acid value is less than 30 mgKOH / g, it tends to require a longer time for alkali development than when the acid value is in the above range, and when it exceeds 200 mgKOH / g, the acid value is in the above range. In comparison with the above, the developer resistance of the unexposed portion tends to be lowered.

  The polystyrene-reduced weight average molecular weight of the polybasic acid anhydride-modified phenol resin by gel permeation chromatography is not particularly limited, but is preferably 300 to 100,000, more preferably 1,000 to 100,000, and still more preferably 2,000 to 75,000. In this case, there exists an advantage that it is excellent in coating-film property and developability.

  The compound which produces | generates an acid with the light which is (B) component is used as a photosensitive agent. The component (B) has a function of generating an acid by light irradiation and increasing the solubility of the light-irradiated portion in the alkaline aqueous solution. As the component (B), a compound generally called a photoacid generator can be used. Specific examples of the component (B) include o-quinonediazide compounds, aryldiazonium salts, diaryliodonium salts, and triarylsulfonium salts. Of these, o-quinonediazide compounds are preferred because of their high sensitivity.

  As the o-quinonediazide compound, for example, a compound obtained by subjecting o-quinonediazidesulfonyl chloride to a hydroxy compound, an amino compound or the like in the presence of a dehydrochlorinating agent can be used.

  Examples of the o-quinonediazidesulfonyl chloride used in the reaction include benzoquinone-1,2-diazide-4-sulfonyl chloride, naphthoquinone-1,2-diazide-5-sulfonyl chloride, and naphthoquinone-1,2-diazide-4- A sulfonyl chloride is mentioned.

  Examples of the hydroxy compound used in the reaction include hydroquinone, resorcinol, pyrogallol, bisphenol A, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) -1- [4- {1- ( 4-hydroxyphenyl) -1-methylethyl} phenyl] ethane, 2,2-bis (4-hydroxyphenyl) hexafluoropropane, 2,3,4-trihydroxybenzophenone, 2,3,4,4′-tetra Hydroxybenzophenone, 2,2 ′, 4,4′-tetrahydroxybenzophenone, 2,3,4,2 ′, 3′-pentahydroxybenzophenone, 2,3,4,3 ′, 4 ′, 5′-hexahydroxy Benzophenone, bis (2,3,4-trihydroxyphenyl) methane, bis (2,3,4-tri Droxyphenyl) propane, 4b, 5,9b, 10-tetrahydro-1,3,6,8-tetrahydroxy-5,10-dimethylindeno [2,1-a] indene, tris (4-hydroxyphenyl) Examples include methane and tris (4-hydroxyphenyl) ethane.

  Examples of the amino compound used in the reaction include p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, and 4,4 ′. -Diaminodiphenyl sulfide, o-aminophenol, m-aminophenol, p-aminophenol, 3,3'-diamino-4,4'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dihydroxybiphenyl, Bis (3-amino-4-hydroxyphenyl) propane, bis (4-amino-3-hydroxyphenyl) propane, bis (3-amino-4-hydroxyphenyl) sulfone, bis (4-amino-3-hydroxyphenyl) Sulfone, bis (3-amino-4-hydroxypheny ) Hexafluoropropane, bis (4-amino-3-hydroxyphenyl) hexafluoropropane and the like.

  Examples of the dehydrochlorinating agent used in the reaction include sodium carbonate, sodium hydroxide, sodium hydrogen carbonate, potassium carbonate, potassium hydroxide, trimethylamine, triethylamine, pyridine and the like. Moreover, as a reaction solvent, dioxane, acetone, methyl ethyl ketone, tetrahydrofuran, diethyl ether, N-methylpyrrolidone, or the like is used.

  o-quinonediazidosulfonyl chloride and hydroxy compound and / or amino compound are blended so that the total number of moles of hydroxy group and amino group is 0.5 to 1 per mole of o-quinonediazidesulfonyl chloride. It is preferred that A preferred blending ratio of the dehydrochlorinating agent and o-quinonediazide sulfonyl chloride is in the range of 0.95 / 1 molar equivalent to 1 / 0.95 molar equivalent. A preferable reaction temperature is 0 to 40 ° C., and a preferable reaction time is 1 to 10 hours.

  The blending amount of the component (B) is preferably 3 to 100 parts by mass with respect to 100 parts by mass of the component (A) from the viewpoint of the difference in dissolution rate between the exposed part and the unexposed part, and the allowable sensitivity range, Mass parts are more preferable, and 5 to 30 parts by mass are most preferable.

  The thermal crosslinking agent of component (C) is a compound that reacts with component (A) to form a bridge structure when the photosensitive resin film after pattern formation is cured by heating. Thereby, brittleness of the film and melting of the film can be prevented. As the component (C), specifically, a compound having a phenolic hydroxyl group, a compound having a hydroxymethylamino group, or a compound having an epoxy group can be used.

  As the compound having a phenolic hydroxyl group, a compound different from the component (A) is used. A compound having a phenolic hydroxyl group can not only serve as a thermal crosslinking agent but also increase the dissolution rate of the exposed area when developing with an alkaline aqueous solution, thereby improving the sensitivity. The molecular weight of the compound having a phenolic hydroxyl group is preferably 2000 or less. Considering the solubility in an aqueous alkali solution and the balance between the photosensitive properties and the cured film properties, the number average molecular weight is preferably 94 to 2000, more preferably 108 to 2000, and still more preferably 108 to 1500.

  As the compound having a phenolic hydroxyl group, a conventionally known compound can be used. The compound represented by the following general formula (II) is effective in promoting the dissolution of the exposed portion and melting at the time of curing the photosensitive resin film. It is particularly preferable because of its excellent balance of preventing effects.

In formula (II), X represents a single bond or a divalent organic group, R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a monovalent organic group, and a plurality of them in the same molecule R ¹ , R ² , R ³ and R ⁴ may be the same or different, s and t each independently represent an integer of 1 to 3, u and v each independently represent an integer of 0 to 4 .

  In general formula (II), the compound in which X is a single bond is a biphenol (dihydroxybiphenyl) derivative. Examples of the divalent organic group represented by X include alkylene groups having 1 to 10 carbon atoms such as methylene group, ethylene group and propylene group, alkylidene groups having 2 to 10 carbon atoms such as ethylidene group, and phenylene groups. An arylene group having 6 to 30 carbon atoms, such as a group in which some or all of the hydrogen atoms of these hydrocarbon groups are substituted with a halogen atom such as a fluorine atom, a sulfonyl group, a carbonyl group, an ether bond, a thioether bond, an amide bond Etc. Among these, X is preferably a divalent organic group represented by the following general formula (III).

  In formula (III), X ′ represents a single bond, an alkylene group (for example, an alkylene group having 1 to 10 carbon atoms), an alkylidene group (for example, an alkylidene group having 2 to 10 carbon atoms), or one of these hydrogen atoms. A group, a sulfonyl group, a carbonyl group, an ether bond, a thioether bond or an amide bond, in which part or all are substituted with a halogen atom. R 'represents a hydrogen atom, a hydroxyl group, an alkyl group or a haloalkyl group, and g represents an integer of 1 to 10. Several R 'may mutually be same or different.

  Examples of the compound having a hydroxymethylamino group include (poly) (N-hydroxymethyl) melamine, (poly) (N-hydroxymethyl) glycoluril, (poly) (N-hydroxymethyl) benzoguanamine, (poly) (N- And nitrogen-containing compounds obtained by alkyl etherifying all or part of active methylol groups such as hydroxymethyl) urea. Here, the alkyl group of the alkyl ether includes a methyl group, an ethyl group, a butyl group, or a mixture thereof, and may contain an oligomer component that is partially self-condensed. Specific examples include hexakis (methoxymethyl) melamine, hexakis (butoxymethyl) melamine, tetrakis (methoxymethyl) glycoluril, tetrakis (butoxymethyl) glycoluril, and tetrakis (methoxymethyl) urea.

  A conventionally well-known thing can be used as a compound which has an epoxy group. Specific examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, alicyclic epoxy resin, glycidyl amine, heterocyclic epoxy resin, polyalkylene glycol diglycidyl ether. Is mentioned.

  Further, as the component (C), in addition to the above, hydroxymethyl such as bis [3,4-bis (hydroxymethyl) phenyl] ether and 1,3,5-tris (1-hydroxy-1-methylethyl) benzene Aromatic compounds having a group, compounds having a maleimide group, such as bis (4-maleimidophenyl) methane and 2,2-bis [4- (4′-maleimidophenoxy) phenyl] propane, compounds having a norbornene skeleton, polyfunctional An acrylate compound, a compound having an oxetanyl group, a compound having a vinyl group, or a blocked isocyanate compound can be used.

  The thermal crosslinking agent mentioned above is used individually by 1 type or in combination of 2 or more types. Among these, from the viewpoint of improving sensitivity and heat resistance, a compound having a hydroxymethyl group is preferable, and a compound having a hydroxymethyl group and a phenolic hydroxyl group and / or a compound having a hydroxymethylamino group are more preferable. The compound having a hydroxymethyl group is particularly preferably a compound having an alkoxymethyl group in which all or part of the hydroxymethyl group is alkyl etherified.

  The blending amount of the component (C) is preferably 1 to 50 parts by mass with respect to 100 parts by mass of the component (A) from the viewpoint of development time, the allowable width of the unexposed part remaining film rate, and the characteristics of the cured film 2 to 30 parts by mass is more preferable, and 3 to 25 parts by mass is most preferable.

  Component (D) is a solvent. By containing the solvent, the positive photosensitive resin composition of the present invention has an effect of facilitating application on the substrate and forming a coating film having a uniform thickness. Specific examples of the solvent include γ-butyrolactone, ethyl lactate, propylene glycol monomethyl ether acetate, benzyl acetate, n-butyl acetate, ethoxyethyl propionate, 3-methylmethoxypropionate, N-methyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, hexamethylphosphorylamide, tetramethylene sulfone, diethyl ketone, diisobutyl ketone, methyl amyl ketone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene Examples include glycol monobutyl ether and dipropylene glycol monomethyl ether.

  These solvents can be used alone or in combination of two or more. Moreover, the compounding quantity of (D) component is although it does not specifically limit, It is preferable to adjust so that the ratio of the solvent in a positive photosensitive resin composition may be 20-90 mass%.

  The positive photosensitive resin composition according to this embodiment preferably contains an elastomer as the component (E) in addition to the components (A) to (D). By using an elastomer, flexibility can be imparted to the cured resin. The glass transition temperature (Tg) of the polymer constituting the elastomer is preferably 20 ° C. or lower.

  Examples of the elastomer include a styrene elastomer, an olefin elastomer, a urethane elastomer, a polyester elastomer, a polyamide elastomer, an acrylic elastomer, and a silicone elastomer. These can be used alone or in combination of two or more.

  Examples of the styrenic elastomer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and styrene-butadiene-methacrylate block. Examples thereof include polymers. As a component constituting the styrene-based elastomer, styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene can be used in addition to styrene.

  Commercially available styrenic elastomers include Tufprene, Solprene T, Asaprene T, Tuftec (above, Asahi Kasei Kogyo Co., Ltd.), Elastomer AR (Aron Kasei Co., Ltd.), Kraton G, Califlex (above, Shell Japan Ltd.) Manufactured), JSR-TR, TSR-SIS, Dynalon (above, manufactured by JSR), Denka STR (manufactured by Electrochemical Co., Ltd.), Quintac (manufactured by Nippon Zeon), TPE-SB series (manufactured by Sumitomo Chemical), Lavalon (Mitsubishi Chemical Co., Ltd.), Septon, Hibler (above, Kuraray Co., Ltd.), Sumiflex (Sumitomo Bakelite Co., Ltd.), Rheostomer, Actimer (above, Riken Vinyl Industry Co., Ltd.), Paraloid EXL series (Rohm and Haas Co., Ltd.) )

  Examples of the olefin elastomer include copolymers of α-olefins having 2 to 20 carbon atoms (for example, ethylene-propylene copolymer (EPR), ethylene-propylene-diene copolymer (EPDM)), and carbon number 2 Copolymer of ~ 20 dienes and α-olefin, carboxy-modified NBR obtained by copolymerizing epoxidized polybutadienebutadiene-acrylonitrile copolymer with methacrylic acid, ethylene-α-olefin copolymer rubber, ethylene-α-olefin -Diene copolymer rubber, propylene-α-olefin copolymer rubber, butene-α-olefin copolymer rubber, and the like. Specific examples of the α-olefin having 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-hexene and 4-methyl-1-pentene. Specific examples of the diene having 2 to 20 carbon atoms include dicyclopentadiene, 1,4-hexadiene, cyclooctane diene, methylene norbornene, ethylidene norbornene, butadiene, and isoprene.

  Commercially available olefin-based elastomers include milastoma (manufactured by Mitsui Petrochemical), EXACT (manufactured by Exxon Chemical), ENGAGE (manufactured by Dow Chemical), Nipol series (manufactured by Nippon Zeon), hydrogenated styrene- Butadiene rubber DYNABON HSBR (manufactured by JSR), butadiene-acrylonitrile copolymer NBR series (manufactured by JSR), XER series of both end carboxyl group-modified butadiene-acrylonitrile copolymers having a crosslinking point (manufactured by JSR), polybutadiene There are partially epoxidized epoxidized polybudadiene BF-1000 (manufactured by Nippon Soda Co., Ltd.) and liquid butadiene-acrylonitrile copolymer HYCAR series (manufactured by Ube Industries).

  The urethane-based elastomer has a hard segment generated from a low molecular (short chain) diol and a diisocyanate, and a soft segment generated from a high molecular (long chain) diol and a diisocyanate. Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6-hexene). Xylene carbonate) and poly (1,6-hexylene-neopentylene adipate). The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000. Low molecular (short chain) diols include ethylene glycol, propylene glycol, 1,4-butanediol and bisphenol A. The number average molecular weight of the short-chain diol is preferably 48 to 500.

  Commercially available urethane-based elastomers include PANDEX T-2185, T-2983N (manufactured by Dainippon Ink & Chemicals, Inc.), sylactolan E790, and the Hitaroid series (manufactured by Hitachi Chemical Co., Ltd.).

  The polyester elastomer is obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof. Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of these aromatic rings are substituted with a methyl group, an ethyl group, a phenyl group, and the like, Examples thereof include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid and dodecanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These compounds can be used alone or in combination of two or more. Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol; Examples include alicyclic diol, bisphenol A, bis- (4-hydroxyphenyl) -methane, bis- (4-hydroxy-3-methylphenyl) -propane, resorcin and the like. These compounds can be used individually by 1 type or in combination of 2 or more types.

  A multi-block copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component can also be used as the polyester elastomer. . Polyester elastomers are available in various grades depending on the types and ratios of hard segments and soft segments, and the difference in molecular weight.

  Commercially available polyester elastomers include Hytrel (manufactured by DuPont-Toray), Perprene (manufactured by Toyobo), and Espel (manufactured by Hitachi Chemical Co., Ltd.).

  Polyamide elastomers are composed of hard segments made of polyamide and soft segments made of polyether or polyester, and are roughly divided into two types: polyether block amide type and polyether ester block amide type. The Examples of the polyamide include polyamide 6, polyamide 11, and polyamide 12. Examples of the polyether include polyoxyethylene, polyoxypropylene, polytetramethylene glycol and the like.

  Commercially available polyamide-based elastomers include UBE polyamide elastomer (manufactured by Ube Industries), Daiamide (manufactured by Daicel Huls), PEBAX (manufactured by Toray Industries, Inc.), Grilon ELY (manufactured by MMS Japan), Novamid (Mitsubishi) Chemical Co., Ltd.) and Glais (Dainippon Ink Chemical Co., Ltd.).

  Acrylic elastomers are acrylic esters such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, monomers having an epoxy group such as glycidyl methacrylate, allyl glycidyl ether, and / or vinyls such as acrylonitrile and ethylene. It is obtained by copolymerizing with a monomer. Examples of the acrylic elastomer include acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, and acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer.

  Silicone elastomers are mainly composed of organopolysiloxane, and are classified into polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. Further, a part of organopolysiloxane modified with a vinyl group, an alkoxy group or the like may be used.

  Specific examples of commercially available silicone elastomers include KE series (manufactured by Shin-Etsu Chemical Co., Ltd.), SE series, CY series, and SH series (manufactured by Toray Dow Corning Silicone Co., Ltd.).

  In addition to the elastomer described above, a rubber-modified epoxy resin can also be used. The rubber-modified epoxy resin includes, for example, a part or all of epoxy groups such as bisphenol F type epoxy resin, bisphenol A type epoxy resin, salicylaldehyde type epoxy resin, phenol novolac type epoxy resin, or cresol novolac type epoxy resin, It is obtained by modifying with a terminal carboxylic acid-modified butadiene-acrylonitrile rubber, a terminal amino-modified silicone rubber or the like.

  The elastomer as component (E) may be elastomer fine particles. The elastomer fine particles described above as the rubbery polymer used to obtain the plasticized phenol resin can be used as the component (E).

  (E) The compounding quantity of the elastomer of a component becomes like this. Preferably it is 1-50 mass parts with respect to 100 mass parts of polybasic acid anhydride modified phenol resin, More preferably, it is 5-30 mass parts. When the amount of the elastomer is less than 1 part by mass, the thermal shock resistance of the resulting cured film tends to decrease, and when it exceeds 50 parts by mass, the resolution and the heat resistance of the cured film tend to decrease, There is a tendency for the compatibility and dispersibility of the to decrease.

  In addition to the components (A) to (D), the positive photosensitive resin composition according to this embodiment includes a compound that generates an acid by heating, a dissolution accelerator, a dissolution inhibitor, a coupling agent, and a surfactant. Or you may further contain other components, such as a leveling agent and a phenol resin.

  By using a compound that generates an acid by heating, it becomes possible to generate an acid when the photosensitive resin film is heated, and the reaction between the component (A) and the component (C), that is, the thermal crosslinking reaction is promoted. The heat resistance of the cured film is improved. In addition, some compounds that generate an acid upon heating generate an acid even when irradiated with light. In this case, the solubility of an exposed portion in an alkaline aqueous solution increases. Therefore, the difference in solubility in the alkaline aqueous solution between the unexposed area and the exposed area is further increased, and the resolution is improved.

  It is preferable that the compound which produces | generates an acid by heating produces | generates an acid by heating to 50-250 degreeC. Specifically, a salt formed from a strong acid such as an onium salt and a base, imide sulfonate, and the like.

  Examples of onium salts include diaryliodonium salts such as aryldiazonium salts, diphenyliodonium salts, diaryliodonium salts, di (alkylaryl) iodonium salts such as di (t-butylphenyl) iodonium salts, and trimethylsulfonium salts. Trialkylsulfonium salts, dialkylmonoarylsulfonium salts such as dimethylphenylsulfonium salt, diarylmonoalkyliodonium salts such as diphenylmethylsulfonium salt, and triarylsulfonium salts.

  Among these, p-toluenesulfonic acid di (t-butylphenyl) iodonium salt, trifluoromethanesulfonic acid di (t-butylphenyl) iodonium salt, trifluoromethanesulfonic acid trimethylsulfonium salt, trifluoromethanesulfonic acid dimethylphenyl Sulfonium salt, diphenylmethylsulfonium salt of trifluoromethanesulfonic acid, di (t-butylphenyl) iodonium salt of nonafluorobutanesulfonic acid, diphenyliodonium salt of camphorsulfonic acid, diphenyliodonium salt of ethanesulfonic acid, dimethyl of benzenesulfonic acid Particularly preferred are phenylsulfonium salts and diphenylmethylsulfonium salts of toluenesulfonic acid.

  As a salt formed from a strong acid and a base, in addition to the above-described onium salt, the following salt formed from a strong acid and a base, such as a pyridinium salt, can also be used. Strong acids include p-toluenesulfonic acid, arylsulfonic acid such as benzenesulfonic acid, camphorsulfonic acid, trifluoromethanesulfonic acid, perfluoroalkylsulfonic acid such as nonafluorobutanesulfonic acid, methanesulfonic acid, ethanesulfonic acid And alkylsulfonic acids such as butanesulfonic acid. Examples of the base include pyridine, alkylpyridines such as 2,4,6-trimethylpyridine, N-alkylpyridines such as 2-chloro-N-methylpyridine, and halogenated-N-alkylpyridines.

  As the imide sulfonate, for example, naphthoyl imide sulfonate or phthalimide sulfonate can be used.

As a compound that generates an acid by heating, in addition to the compounds described above, a compound having a structure represented by the following general formula (IV) or a compound having a sulfonamide structure represented by the following general formula (V) may be used. it can.
R ⁵ R ⁶ C═N—O—SO ₂ —R ⁷ (IV)
—NH—SO ₂ —R ⁸ (V)

In formula (IV), R ⁵ is, for example, a cyano group, and R ⁶ is, for example, a methoxyphenyl group or a phenyl group. R ⁷ is, for example, an aryl group such as a p-methylphenyl group and a phenyl group, an alkyl group such as a methyl group, an ethyl group, and an isopropyl group, or a perfluoroalkyl group such as a trifluoromethyl group and a nonafluorobutyl group. is there.

In formula (V), R ⁸ represents, for example, an alkyl group such as a methyl group, an ethyl group and a propyl group, an aryl group such as a methylphenyl group and a phenyl group, or a perfluoro such as a trifluoromethyl group and nonafluorobutyl. It is an alkyl group. Examples of the group bonded to the N atom of the sulfonamide structure represented by the general formula (V) include 2,2′-bis (4-hydroxyphenyl) hexafluoropropane and 2,2′-bis (4-hydroxy). Phenyl) propane, and di (4-hydroxyphenyl) ether.

  0.1-30 mass parts is preferable with respect to 100 mass parts of (A) component, as for the compounding quantity of the compound which produces | generates an acid by heating, 0.2-20 mass parts is more preferable, 0.5-10 mass parts Is more preferable.

  By blending the dissolution accelerator in the positive photosensitive resin composition described above, the dissolution rate of the exposed area when developing with an alkaline aqueous solution can be increased, and the sensitivity and resolution can be improved. A conventionally well-known thing can be used as a dissolution promoter. Specific examples thereof include compounds having a carboxyl group, a sulfonic acid, and a sulfonamide group.

  The compounding quantity of a solubility promoter can be determined with the melt | dissolution rate with respect to alkaline aqueous solution, for example, is 0.01-30 mass parts with respect to 100 mass parts of (A) component.

  A dissolution inhibitor is a compound that inhibits the solubility of the component (A) in an alkaline aqueous solution, and is used to control the remaining film thickness, development time, and contrast. Specific examples thereof include diphenyliodonium nitrate, bis (p-tert-butylphenyl) iodonium nitrate, diphenyliodonium bromide, diphenyliodonium chloride, diphenyliodonium iodide and the like. In the case where a dissolution inhibitor is blended, the blending amount is preferably 0.01 to 20 parts by weight with respect to 100 parts by weight of component (A), in terms of sensitivity and an allowable range of development time, and 0.01 to 15 Mass parts are more preferable, and 0.05 to 10 parts by mass are even more preferable.

  By mix | blending a coupling agent with the said positive photosensitive resin composition, the adhesiveness with the board | substrate of the cured film formed can be improved. Examples of the coupling agent include organic silane compounds and aluminum chelate compounds.

  Examples of the organic silane compound include vinyltriethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, urea propyltriethoxysilane, methylphenylsilanediol, ethylphenylsilanediol, n- Propylphenylsilanediol, isopropylphenylsilanediol, n-butylsiphenylsilanediol, isobutylphenylsilanediol, tert-butylphenylsilanediol, diphenylsilanediol, ethylmethylphenylsilanol, n-propylmethylphenylsilanol, isopropylmethylphenylsilanol , N-butylmethylphenylsilanol, isobutylmethylphenylsilanol, tert-butylmethylphenylsilanol , Ethyl n-propylphenylsilanol, ethylisopropylphenylsilanol, n-butylethylphenylsilanol, isobutylethylphenylsilanol, tert-butylethylphenylsilanol, methyldiphenylsilanol, ethyldiphenylsilanol, n-propyldiphenylsilanol, isopropyldiphenylsilanol , N-butyldiphenylsilanol, isobutyldiphenylsilanol, tert-butyldiphenylsilanol, phenylsilanetriol, 1,4-bis (trihydroxysilyl) benzene, 1,4-bis (methyldihydroxysilyl) benzene, 1,4-bis (Ethyldihydroxysilyl) benzene, 1,4-bis (propyldihydroxysilyl) benzene, 1,4-bis (butyldi) Droxysilyl) benzene, 1,4-bis (dimethylhydroxysilyl) benzene, 1,4-bis (diethylhydroxysilyl) benzene, 1,4-bis (dipropyldroxysilyl) benzene, and 1,4-bis (dibutyl) Hydroxysilyl) benzene.

  When using a coupling agent, the compounding quantity is preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass with respect to 100 parts by mass of the component (A).

  By adding the surfactant or leveling agent to the positive photosensitive resin composition, it is possible to prevent coatability, for example, striation (thickness unevenness) or improve developability. Examples of the surfactant or leveling agent include polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene octylphenol ether. Commercially available products include Megafax F171, F173, R-08 (trade name, manufactured by Dainippon Ink & Chemicals, Inc.), Florard FC430, FC431 (trade name, Sumitomo 3M Limited), organosiloxane polymers KP341, KBM303, KBM403, KBM803. (Trade name manufactured by Shin-Etsu Chemical Co., Ltd.).

  When using a surfactant or a leveling agent, the compounding amount is preferably 0.001 to 5 parts by mass and more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the component (A).

  By adding a phenol resin to the positive photosensitive resin composition, the resolution and dissolution contrast can be further improved, and the heat resistance of the cured film can be improved. Specific examples of the phenol resin include phenol / formaldehyde novolak resin, cresol / formaldehyde novolak resin, xylylenol / formaldehyde novolak resin, resorcinol / formaldehyde novolak resin, phenol-naphthol / formaldehyde novolak resin, and the like.

  When using a phenol resin, it is used in a blending amount within a range that does not impair the toughness of the cured film. Specifically, the blending amount of the phenol resin is preferably 0.1 to 50 parts by mass and more preferably 1 to 30 parts by mass with respect to 100 parts by mass of the component (A).

  The positive photosensitive resin composition according to this embodiment can be developed using an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH). By using the positive photosensitive resin composition according to the present embodiment, it is possible to form a resist pattern having a good shape having good adhesion and heat resistance with sufficiently high sensitivity and resolution.

  In the method for producing a resist pattern according to the present embodiment, a positive photosensitive resin composition is applied on a support substrate, and the applied positive photosensitive resin composition is dried to form a photosensitive resin film ( A film forming step), a step of exposing the photosensitive resin film (exposure step), a step of developing the exposed photosensitive resin film with an alkaline aqueous solution to form a resist pattern (developing step), a resist And a step of heating the pattern (heating step).

Film-forming process In the film-forming process, the positive photosensitive resin composition described above is applied to a support substrate such as a glass substrate, a semiconductor, a metal oxide insulator (for example, TiO ₂ , SiO ₂ ), or silicon nitride, and a spinner or the like. Apply by spin coating. The applied positive photosensitive resin composition is dried by heating using a hot plate, oven or the like. Thereby, a film (photosensitive resin film) of the positive photosensitive resin composition is formed on the support substrate.

Exposure Step In the exposure step, the photosensitive resin film is irradiated with actinic rays such as ultraviolet rays, visible rays, and radiations through a mask. Since the polybasic acid anhydride-modified phenol resin is highly transparent to i-line, i-line irradiation can be preferably used. After the exposure, if necessary, post-exposure heating (PEB) may be performed before proceeding to the development step. The post-exposure heating temperature is preferably 70 ° C. to 140 ° C., and the post-exposure heating time is preferably 1 minute to 5 minutes.

Development Step In the development step, a resist pattern is formed by removing a portion (exposed portion) of the photosensitive resin film irradiated with actinic rays with a developer. The developer is preferably an aqueous alkali solution such as sodium hydroxide, potassium hydroxide, sodium silicate, ammonia, ethylamine, diethylamine, triethylamine, triethanolamine, and tetramethylammonium hydroxide (TMAH). The base concentration of these aqueous solutions is preferably 0.1 to 10% by weight. Furthermore, alcohols and surfactants may be added to the developer. Each of these can be blended in the range of preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the developer.

Heating Step In the heating step, the photosensitive resin composition is cured by heating the resist pattern formed by development. The heating temperature is 250 ° C. or less, desirably 225 ° C. or less, and more desirably 140 to 200 ° C.

  Heating can be performed using a heating means selected from a quartz tube furnace, a hot plate, rapid thermal annealing, a vertical diffusion furnace, an infrared curing furnace, an electron beam curing furnace, and a microwave curing furnace. In addition, either air or an inert atmosphere such as nitrogen can be selected. However, it is preferable to perform the process under nitrogen because the oxidation of the photosensitive resin film can be prevented. Since the said heating temperature range is lower than the conventional heating temperature, the damage to a support substrate or a device can be restrained small. Therefore, by using the resist pattern manufacturing method according to this embodiment, devices can be manufactured with high yield. It also leads to energy savings in the process. Furthermore, since the positive photosensitive resin composition according to the present embodiment has a small volume shrinkage (curing shrinkage) in the heating process found in photosensitive polyimide and the like, it is possible to prevent a reduction in dimensional accuracy.

  The heating time in the heating step is appropriately adjusted so that the positive photosensitive resin composition is sufficiently cured. Specifically, approximately 5 hours or less is preferable in consideration of work efficiency.

  A microwave curing furnace can also be used as the heating means. The microwave curing furnace may be a variable frequency microwave curing apparatus. By using a microwave curing furnace, it is possible to effectively heat only the photosensitive resin film while keeping the temperature of the substrate or device at, for example, 200 ° C. or lower.

  The variable frequency microwave curing apparatus is preferable in that the microwave is irradiated in pulses while changing its frequency, so that standing waves can be prevented and the substrate surface can be heated uniformly. In addition, when a metal wiring is included as an electronic component to be described later as a substrate, the occurrence of discharge from the metal can be prevented by irradiating microwaves in a pulsed manner while changing the frequency, and the electronic component is protected from destruction. It is preferable in that it can be performed. Furthermore, it is preferable to heat using a frequency-variable microwave because the cured film properties do not deteriorate even if the curing temperature is lowered as compared with an oven.

  The frequency of the frequency variable microwave is in the range of 0.5 to 20 GHz, but is practically preferably in the range of 1 to 10 GHz, and more preferably in the range of 2 to 9 GHz. Moreover, the frequency of the microwave to be irradiated may be continuously changed, or the frequency may be changed in a stepwise manner. At that time, the shorter the time for irradiating a single-frequency microwave, the less likely it is that standing waves or metal discharges occur, and the time is preferably 1 millisecond or less, particularly preferably 100 microseconds or less.

  The output of the microwave to be irradiated varies depending on the size of the apparatus and the amount of the object to be heated, but is generally in the range of 10 to 2000 W, practically preferably 100 to 1000 W, more preferably 100 to 700 W, further preferably 100 to 700 W. 500 W is most preferred. If the output is 10 W or less, it is difficult to heat the object to be heated in a short time, and if it is 2000 W or more, a rapid temperature rise is likely to occur.

  It is preferable to irradiate the microwave by turning it on / off in a pulsed manner. By irradiating the microwaves in a pulsed manner, it is preferable in that the set heating temperature can be maintained and damage to the cured film and the substrate can be avoided. Although the time for irradiating the pulsed microwave at one time varies depending on the conditions, it is preferably about 10 seconds or less.

  As an application example of a resist pattern manufacturing method, an embodiment of a semiconductor device manufacturing process will be described with reference to the drawings. 1 to 5 are schematic sectional views showing an embodiment of a manufacturing process of a semiconductor device having a multilayer wiring structure.

  In the manufacturing method according to the present embodiment, first, a structure 100 shown in FIG. 1 is prepared. The structure 100 includes a semiconductor substrate 1 such as an Si substrate having circuit elements, a protective film 2 such as a silicon oxide film covering the semiconductor substrate 1 having a predetermined pattern from which the circuit elements are exposed, and on the exposed circuit elements. And the interlayer insulating film 4 made of a polyimide resin or the like formed on the protective film 2 and the first conductor layer 3 by a spin coating method or the like.

  Next, by forming the photosensitive resin layer 5 having the window portion 6A on the interlayer insulating film 4, the structure 200 shown in FIG. 2 is obtained. The photosensitive resin layer 5 is formed, for example, by applying a photosensitive resin such as chlorinated rubber, phenol novolac, polyhydroxystyrene, or polyacrylate ester by a spin coating method. The window portion 6A is formed so that a predetermined portion of the interlayer insulating film 4 is exposed by a known photolithography technique.

  After the interlayer insulating film 4 is etched to form the window 6B, the photosensitive resin layer 5 is removed to obtain a structure 300 shown in FIG. For etching the interlayer insulating film 4, dry etching means using a gas such as oxygen or carbon tetrafluoride can be used. By this etching, the portion of the interlayer insulating film 4 corresponding to the window portion 6A is selectively removed, and the interlayer insulating film 4 provided with the window portion 6B so that the first conductor layer 3 is exposed is obtained. Next, the photosensitive resin layer 5 is removed using an etching solution that corrodes only the photosensitive resin layer 5 without corroding the first conductor layer 3 exposed from the window 6B.

  Furthermore, the 2nd conductor layer 7 is formed in the part corresponding to the window part 6B, and the structure 400 shown in FIG. 4 is obtained. A known photolithography technique can be used to form the second conductor layer 7. As a result, the second conductor layer 7 and the first conductor layer 3 are electrically connected.

  Finally, the surface protective layer 8 is formed on the interlayer insulating film 4 and the second conductor layer 7 to obtain the semiconductor device 500 shown in FIG. In the present embodiment, the surface protective layer 8 is formed as follows. First, the positive photosensitive resin composition according to the above-described embodiment is applied onto the interlayer insulating film 4 and the second conductor layer 7 by spin coating, and dried to form a photosensitive resin film. Next, after light irradiation through a mask on which a pattern corresponding to the window 6C is drawn at a predetermined portion, the photosensitive resin film is patterned by developing with an alkaline aqueous solution. Thereafter, the photosensitive resin curtain is cured by heating to form a film as the surface protective layer 8. The surface protective layer 8 protects the first conductor layer 3 and the second conductor layer 7 from external stress, α rays, and the like, and the obtained semiconductor device 500 is excellent in reliability.

  In the above-described embodiment, the method for manufacturing a semiconductor device having a two-layer wiring structure is shown. However, when a multilayer wiring structure having three or more layers is formed, the above steps are repeated to form each layer. Can do. That is, it is possible to form a multilayer pattern by repeating each step of forming the interlayer insulating film 4 and each step of forming the surface protective layer 8. In the above example, not only the surface protective layer 8 but also the interlayer insulating film 4 can be formed using the positive photosensitive resin composition according to the present embodiment.

  The electronic component according to the present embodiment has a resist pattern formed by the above-described manufacturing method. The electronic component includes a semiconductor device, a multilayer wiring board, and various electronic devices. Specifically, the electronic component according to this embodiment includes an interlayer insulating film layer, a surface protective film, a cover coat layer, a core for a rewiring layer, a collar for holding a conductive ball as an external connection terminal, and The resist pattern is included as at least one structural material selected from the group consisting of underfill. Other structures of the electronic component are not particularly limited.

  6 and 7 are schematic cross-sectional views showing an embodiment of a semiconductor device. The semiconductor device 600 shown in FIG. 6 includes a silicon chip 23, an interlayer insulating film 11 provided on one surface side of the silicon chip 23, and an Al having a pattern including the pad portion 15 formed on the interlayer insulating film 11. A wiring layer 12, an insulating layer 13 (for example, a P-SiN layer) and a surface protective layer 14, which are sequentially stacked on the interlayer insulating film 11 and the Al wiring layer 12 while forming an opening on the pad portion 15, and a surface protective layer 14 is in contact with the pad portion 15 in the openings of the insulating layer 13 and the surface protective layer 14 and is opposite to the surface protective layer 14 of the core 18 for the rewiring layer. And a rewiring layer 16 extending on the surface protective layer 14 so as to be in contact with the surface. Further, the semiconductor device 600 is formed so as to cover the surface protective layer 14, the core 18, and the rewiring layer 16, and a cover coat layer 19 in which an opening is formed in a portion of the rewiring layer 16 on the core 18. The conductive ball 17 connected to the rewiring layer 16 with the barrier metal 20 interposed therebetween in the opening of the layer 19, the collar 21 that holds the conductive ball, and the cover coat layer 19 around the conductive ball 17 are provided. The underfill 22 is provided. The conductive ball 17 is used as an external connection terminal and is formed of solder, gold or the like. The underfill 22 is provided to relieve stress when the semiconductor device 600 is mounted.

  In the semiconductor device 700 of FIG. 7, an Al wiring layer (not shown) and a pad portion 15 of the Al wiring layer are formed on the silicon chip 23, and an insulating layer 13 is formed on the Al wiring layer. A surface protective layer 14 is formed. A rewiring layer 16 is formed on the pad portion 15, and the rewiring layer 16 extends to an upper portion of the connection portion 24 with the conductive ball 17. Further, a cover coat layer 19 is formed on the surface protective layer 14. The rewiring layer 16 is connected to the conductive ball 17 through the barrier metal 20.

6 and 7, the structural material selected from the interlayer insulating layer 11, the surface protective film layer 14, the cover coat layer 19, the core 18, the collar 21, and the underfill 22 is a positive photosensitive material according to this embodiment. It is a resist pattern formed with a resin composition. The resist pattern, which is a cured film formed from the positive photosensitive resin composition according to the present embodiment, is excellent in adhesion to a metal layer such as the Al wiring layer 12 and the rewiring layer 16, sealant, and the like. The mitigation effect is also high. Therefore, the semiconductor device using this cured film for the surface protective layer 14, the cover coat layer 19, the core 18 for rewiring, the ball collar 21 such as solder, or the underfill 12 used in the flip chip is extremely reliable. It will be excellent.
The positive photosensitive resin composition of the present invention is particularly preferably used for the surface protective layer 14 and / or the cover coat layer 19 of the semiconductor device having the rewiring layer 16 in FIGS.
The film thickness of the surface protective layer or the cover coat layer is preferably 3 to 20 μm, and more preferably 5 to 15 μm.

  By using the positive photosensitive resin composition according to this embodiment, curing can be performed even at a low temperature of 200 ° C. or lower in the above heating step that conventionally required 300 ° C. or higher. In the heat treatment step, the heating temperature is preferably 100 ° C to 200 ° C, more preferably 150 ° C to 200 ° C. Furthermore, since the positive photosensitive resin composition according to the present embodiment has a small volume shrinkage (curing shrinkage) in the heating process found in photosensitive polyimide and the like, it is possible to prevent a reduction in dimensional accuracy. A cured film formed from the positive photosensitive resin composition has a high glass transition temperature. Therefore, it becomes a surface protective film or cover coat layer excellent in heat resistance. As a result, an electronic component such as a semiconductor device having excellent reliability can be obtained with high yield and high yield.

  Hereinafter, the present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples.

Synthesis synthesis example 1 of polybasic acid-modified phenolic resin
54 parts by mass of formalin (aldehyde) is added to 216 parts by mass of a mixture obtained by mixing m-cresol and p-cresol in a mass ratio of 50:50, and 2.2 parts by mass of oxalic acid (catalyst) is further added. The mixture was stirred at 90 ° C. for 3 hours. Thereafter, the reaction solution was heated to 120 ° C. and stirred under reduced pressure for 3 hours to obtain a novolac type phenol resin having a weight average molecular weight of 10,000. 85 g of the obtained novolak-type phenol resin, 23 g of tetrahydrophthalic anhydride (polybasic acid anhydride), and 0.9 g of triethylamine (catalyst) were mixed and reacted at 100 ° C. to obtain a polybasic acid-modified phenol resin A1. (Acid value 100 mg KOH / g) was obtained.

Synthesis example 2
54 parts by mass of formalin (aldehyde) is added to 216 parts by mass of a mixture obtained by mixing m-cresol and p-cresol in a mass ratio of 50:50, and 2.2 parts by mass of oxalic acid (catalyst) is further added. The mixture was stirred at 90 ° C. for 3 hours. Thereafter, the reaction solution was heated to 120 ° C. and stirred under reduced pressure for 3 hours to obtain a novolac type phenol resin having a weight average molecular weight of 10,000. 85 g of the obtained novolak-type phenol resin, 12 g of succinic anhydride (polybasic acid anhydride), and 0.9 g of triethylamine (catalyst) were mixed and reacted at 100 ° C. to obtain polybasic acid-modified phenol resin A2. Obtained (acid value 80 mg KOH / g).

Synthesis example 3
To 100 parts by mass of phenol, 43 parts by mass of linseed oil, which is a drying oil, and 0.1 parts by mass of trifluoromethanesulfonic acid, which is an acidic catalyst, are mixed and reacted at 120 ° C. for 2 hours to modify the drying oil. A phenol derivative was obtained.

  130 g of the obtained dry oil-modified phenol derivative, 16.3 g of paraformaldehyde, and 1.0 g of oxalic acid were mixed and stirred at 90 ° C. for 3 hours. Thereafter, the reaction solution was heated to 120 ° C. and stirred for 3 hours under reduced pressure. Next, 29 g (polybasic acid anhydride) of succinic anhydride and 0.3 g of triethylamine were added and stirred at normal pressure and 100 ° C. for 1 hour. The reaction solution was cooled to room temperature to obtain a polybasic acid-modified phenol resin A3 (acid value 120 mgKOH / g).

Synthesis example 4
m-cresol and p-cresol were mixed at a mass ratio of 60:40. Next, with respect to 100 parts by mass of the total amount of m-cresol and p-cresol, 11 parts by mass of a liquid butadiene-acrylonitrile copolymer (Ube Industries, Ltd. trade name HYCAR CTBNX-1300) which is a rubber-like polymer, and an acidic catalyst Was mixed with 0.1 part by mass of trifluoromethanesulfonic acid and reacted at 120 ° C. for 2 hours to obtain a phenol derivative modified with a rubber-like polymer.

  130 g of the phenol derivative modified with the rubbery polymer obtained above, 16.3 g of paraformaldehyde (aldehydes) and 1.0 g of oxalic acid were mixed and stirred at 90 ° C. for 3 hours. Thereafter, the reaction solution was heated to 120 ° C. and stirred for 3 hours under reduced pressure. Next, 29 g (polybasic acid anhydride) of succinic anhydride and 0.3 g of triethylamine were added and stirred at normal pressure and 100 ° C. for 1 hour. The reaction solution was cooled to room temperature to obtain a polybasic acid-modified phenol resin A4 (acid value 130 mgKOH / g).

Synthesis synthesis example 5 of novolak type phenol resin
m-cresol and p-cresol were mixed at a mass ratio of 50:50. 54 parts by mass of formalin (aldehyde) was added to 216 parts by mass of this mixed solution, 2.2 parts by mass of oxalic acid (catalyst) was further added, and the mixture was stirred at 90 ° C. for 3 hours. Thereafter, the temperature of the reaction solution was raised to 120 ° C. and stirred for 3 hours under reduced pressure to obtain a novolak type phenol resin α having a weight average molecular weight of 10,000.

Preparation of positive photosensitive resin composition 100 parts by mass of component (A) (polybasic acid-modified phenolic resins A1 to A4) obtained in Synthesis Examples 1 to 4 or 100 parts by mass of novolak type phenol resin obtained in Synthesis Example 5 Table 1 shows the component (B), a compound that generates an acid by light, a component (C), a thermal crosslinking agent, a component (D), a solvent, and an elastomer (E). Further, 2 parts by mass of a 50% methanol solution of urea propyltriethoxysilane was added as a coupling agent. This solution was filtered under pressure using a Teflon (registered trademark) filter having a pore size of 3 μm to obtain positive photosensitive resin compositions (M1 to M10).

The following raw materials were used in the formulation of the positive photosensitive resin composition shown in Table 1. In Table 1, numerical values in parentheses are blending amounts (parts by mass) with respect to 100 parts by mass of component (A).
(B) Component B1: 1-naphthoquinone-2-diazide of 1,1-bis (4-hydroxyphenyl) -1- [4- {1- (4-hydroxyphenyl) -1-methylethyl} phenyl] ethane 5-sulfonic acid ester (esterification rate: about 90%, trade name TPPA528 manufactured by AZ Electronic Materials)
B2: 1-naphthoquinone-2-diazide-5-sulfonic acid ester of tris (4-hydroxyphenyl) methane (esterification rate: about 95%)
(C) Component C1: 1,1-bis {3,5-bis (methoxymethyl) -4-hydroxyphenyl} methane (trade name TMOM-pp-BPF manufactured by Honshu Chemical Industry Co., Ltd.)
C2: Hexakis (methoxymethyl) melamine (trade name, Nikalac MW-30HM, Sanwa Chemical Co., Ltd.)
(D) Component D1: γ-butyrolactone / propylene glycol monomethyl ether acetate = 90/10 (mass ratio)
D2: Ethyl lactate was used.
(E) Component E1: Butadiene-styrene-methacrylate copolymer (Rohm and Haas product name Paraloid EXL2655)
E2: Liquid butadiene-acrylonitrile copolymer (Ube Industries, Ltd. trade name HYCAR CTBNX-1300)

  Table 1 shows the observation results of the appearance of the resin composition. The case where the appearance of the resin composition was transparent was designated as “A”, the case where it was slightly cloudy was designated as “B”, and the case where it was extremely cloudy was designated as “C”. From the viewpoint of sensitivity and resolution, the appearance of the resin composition is preferably transparent.

Photosensitive characteristics A positive photosensitive resin composition solution (M1 to M10) was spin-coated on a silicon substrate and heated at 100 ° C. for 5 minutes to form a coating film having a thickness of 11 to 13 μm. Thereafter, reduction projection exposure was performed with i-line (365 nm) through a mask using an i-line stepper (FPA-3000iW manufactured by Canon). After the exposure, development was performed with a 2.38% aqueous solution of tetramethylammonium hydroxide (TMAH), and development was performed so that the remaining film thickness was about 85 to 95% of the initial film thickness. Then, it rinsed with water. The minimum exposure required for pattern formation was taken as sensitivity, and the width of the smallest square hole pattern that was opened was taken as resolution. Furthermore, the presence or absence of residue in the pattern opening was examined. The results are shown in Table 2.

Production of Cured Film A positive photosensitive resin composition (M1 to M10) was spin-coated on a silicon substrate and heated at 100 ° C. for 5 minutes to form a coating film having a thickness of about 12 to 14 μm. Then, it exposed to all the wavelengths through the mask with respect to the coating film of resin M1-M10 using the proximity exposure machine (PLA-600FA by Canon). After exposure, development was performed with a 2.38% aqueous solution of TMAH to obtain a 10 mm wide rectangular pattern.

The obtained rectangular pattern was heat-treated under the following conditions (i) or (ii) to obtain a cured film having a thickness of about 10 μm. Table 3 shows the shrinkage ratio of the film thickness accompanying curing (= [1− (film thickness after curing / film thickness before curing)] × 100) [%].
(I) Using a vertical diffusion furnace (μ-TF manufactured by Koyo Thermo Systems Co., Ltd.), the coating film is heat-treated in nitrogen at a temperature of 175 ° C. (heating time: 1.5 hours) for 2 hours.
(Ii) Using a frequency-variable microwave curing furnace (Microcure 2100 manufactured by Lambda Technology Co., Ltd.), microwave output 450 W, microwave frequency 5.9 to 7.0 GHz, temperature 165 ° C. (temperature rising time 5 minutes), heating for 2 hours To process.

Cured Film Properties The cured film was peeled from the silicon substrate, and the glass transition temperature (Tg) was measured using TMA / SS600 manufactured by Seiko Instruments Inc. The sample for Tg measurement had a width of 2 mm, a film thickness of 9 to 11 μm, and a chuck distance of 10 mm. The load was 10 gf, and the rate of temperature increase was 5 ° C./min.

  The average breaking elongation (EL) of the cured film was measured using an autograph AGS-H100N manufactured by Shimadzu Corporation. The width of the sample for measuring average elongation at break was 10 mm, the film thickness was 9 to 11 μm, and the distance between chucks was 20 mm. The pulling speed was 5 mm / min, and the measurement temperature was about room temperature (20 ° C. to 25 ° C.). About the cured film obtained on the same conditions, the breaking elongation of five or more samples was measured, and the average value of the measured values at that time was defined as “average breaking elongation (EL)”. Table 3 shows the curing conditions, Tg, and EL.

Stud pull test A positive photosensitive resin composition (M1 to M10) was spin-coated on a substrate (which was formed by sputtering TiN on a silicon substrate and then sputtered with copper), and heated at 100 ° C. for 5 minutes. A coating film having a thickness of about 12 to 14 μm was formed. This coating film was cured under the conditions (i) or (ii) of “Preparation of cured film” to obtain a cured film having a thickness of about 10 μm. The cured film was cut into small pieces together with the substrate, and the aluminum stud and the cured film were joined via an epoxy resin layer. Subsequently, the stud was pulled and the load at the time of peeling was measured. The results are shown in Table 4. In Table 4, the value of the load can be converted to MPa according to the relationship of 1 kgf / cm ² = 0.1 MPa.

Temperature cycle test A positive photosensitive resin composition (M1 to M10) was spin-coated on a substrate on which a rewiring was formed, and heated at 100 ° C. for 5 minutes to form a coating film having a thickness of about 20 μm. For this coating, using a proximity exposure machine (Canon PLA-600FA), exposure was performed at all wavelengths via a mask (500mJ / cm ^2). After the exposure, development was performed with a 2.38% aqueous solution of TMAH to form a via hole having a diameter of 100 μm. The developed coating film was cured under the conditions (i) or (ii) of “Preparation of cured film” to form a cured film as a cover coat film. After forming an under barrier metal in the opening, the solder ball was bumped to produce a test part having the same configuration as in FIG. Furthermore, a test part was mounted and sealed to obtain a test sample. After the test sample was subjected to a temperature cycle test (−55 ° C. to 125 ° C., 2000 cycles), the presence or absence of defects such as cracks and peeling was observed. The results are shown in Table 4. The number of test samples was 10, and the number of defects after the temperature cycle test is shown in the table. In the table, the number of defects is 0 for A, the number of defects is 1-2 for B, the number of defects is 3 to 4 for C, the number of defects is 5 to 7 for D, and the number of defects is 8 or more for E. It was.

Examination of results As is clear from the photosensitive properties shown in Table 2, the positive photosensitive resin compositions M1 to M8 (Examples 1 to 8) using polybasic acid anhydride-modified phenol resins have high sensitivity and resolution. It was. On the other hand, the sensitivity and resolution of the photosensitive resin composition M9 (Comparative Example 1) using a phenol resin not modified with a polybasic acid anhydride is slightly lower than those of M1 to M8, and further, in the pattern opening after development. It was found that a residue was formed. The sensitivity of M7 and M8 (Examples 7 and 8), in which the appearance of the resin composition was slightly turbid, was slightly lowered as compared with the resin compositions M1 to M6 (Examples 1 to 6) having a transparent appearance.

  As shown in Table 3, the shrinkage rate of the film when the film (pre-baked film) before curing of the positive photosensitive resin composition was heat-treated (cured) was any of M1 to M8 (Examples 1 to 8). In the case of, the value was as low as 16% or less. Further, the positive photosensitive resin compositions M1 to M8 exhibited good Tg (185 ° C. or higher) and EL (7% or higher) even when cured at 175 ° C. Furthermore, in Example 1, Tg and EL equivalent to a 175 degreeC thermosetting (curing condition i) film | membrane were shown by 165 degreeC microwave hardening (curing condition ii).

  As shown in Table 4, in the stud pull test, the load at the time of peeling of the cured film of the positive photosensitive resin compositions M1 to M8 was high, and it was found that these resin compositions have high adhesion to copper. Since the adhesiveness to copper is high, it can be said that the positive photosensitive resin composition according to the present invention is particularly useful for forming a core for a rewiring layer, for example. M1 to M8 were also confirmed to have high thermal shock resistance. In particular, M5 and M6 did not cause any defects such as cracks and peeling in the test samples after the temperature cycle test. On the other hand, the cured film of the resin composition M9 (Comparative Example 1) using a phenol resin not modified with a polybasic acid anhydride was brittle, and Tg and EL could not be measured. Moreover, Tg of the cured film of the resin composition M10 (comparative example 2) which does not contain a thermal crosslinking agent was greatly reduced as compared with M1 to M8. Furthermore, the adhesion of M10 to copper was low, and the thermal shock resistance was also low.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate, 2 ... Protective film, 3 ... 1st conductor layer, 4 ... Interlayer insulation film, 5 ... Photosensitive resin layer,
6A, 6B, 6C ... windows, 7 ... second conductor layer, 8 ... surface protective layer, 11 ... interlayer insulating film, 12 ...
Wiring layer, 12 ... underfill, 13 ... insulating layer, 14 ... surface protective layer, 15 ... pad portion, 1
6 ... Rewiring layer, 17 ... Conductive ball, 18 ... Core, 19 ... Cover coat layer, 20 ... Barrier metal, 21 ... Color, 22 ... Underfill, 23 ... Silicon chip, 24 ... Connection part,
100, 200, 300, 400 ... structure, 500 ... semiconductor device, 600 ... semiconductor device,
700: Semiconductor device.

Claims (16)

(A) a polybasic acid anhydride-modified phenol resin obtained by reacting a polybasic acid anhydride with a phenolic hydroxyl group of a phenol resin;
(B) a compound that generates an acid by light;
(C) a thermal crosslinking agent;
(D) a solvent;
A positive photosensitive resin composition comprising:   The positive photosensitive resin composition according to claim 1, wherein the phenol resin is modified with a drying oil or a rubbery polymer. The photosensitive resin composition of Claim 1 or 2 in which the said (A) component has a bivalent group represented by the following general formula (I) in a molecule | numerator.

[In the formula (I), R represents a polycarboxylic acid anhydride residue. ]   The positive photosensitive resin composition as described in any one of Claims 1-3 whose acid value of the said (A) component is 30-200 mgKOH / g.   The positive photosensitive resin composition as described in any one of Claims 1-4 whose said (B) component is an o-quinonediazide compound.   (E) The positive photosensitive resin composition as described in any one of Claims 1-5 which further contains an elastomer.   The positive photosensitive resin composition as described in any one of Claims 1-6 containing 3-100 mass parts of said (B) components with respect to 100 mass parts of said (A) components.   The positive photosensitive resin composition as described in any one of Claims 1-7 containing 1-50 mass parts of said (C) component with respect to 100 mass parts of said (A) component. The process of apply | coating the positive photosensitive resin composition as described in any one of Claims 1-8 on a support substrate, and drying the applied positive photosensitive resin composition, and forming a photosensitive resin film. When,
Exposing the photosensitive resin film;
Developing the photosensitive resin film after exposure with an alkaline aqueous solution to form a resist pattern; and
Heating the resist pattern;
A method for producing a resist pattern comprising:   The method for producing a resist pattern according to claim 9, comprising a step of heating the resist pattern at 200 ° C. or lower.   An electronic component having a resist pattern produced by the method for producing a resist pattern according to claim 9 as an interlayer insulating film layer or a surface protective film.   The electronic component which has a resist pattern manufactured by the manufacturing method of the resist pattern of Claim 9 or 10 as a cover coat layer.   An electronic component having the resist pattern manufactured by the method for manufacturing a resist pattern according to claim 9 or 10 as a core for a rewiring layer.   An electronic component having the resist pattern manufactured by the method for manufacturing a resist pattern according to claim 9 or 10 as a collar for holding a conductive ball as an external connection terminal.   The electronic component which has a resist pattern manufactured by the manufacturing method of the resist pattern of Claim 9 or 10 as an underfill.   An electronic component having a resist pattern formed by the method for producing a resist pattern according to claim 9 as a surface protective layer and / or a cover coat layer for a rewiring layer.

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