JP2008164833A - Negative photosensitive insulating resin composition and cured product of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive insulating resin composition excellent in various properties such as resolution and thermal shock resistance, and capable of forming a surface protective film and an interlayer dielectric showing low curing shrink property and low water-absorbing property. <P>SOLUTION: The photosensitive insulating resin composition comprises an alkali-soluble resin (A1) having a constitutional unit represented by formula (1) (wherein R represents a 1-4C alkyl group, a 1-4C alkoxy group, a halogen atom or a hydroxyl group, and m represents an integer of 0-3), an alkali-soluble resin (A2) other than the resin (A1), a photoacid generator (B), a compound (C) having a functional group capable of reacting with the resin (A1), an oxirane ring-containing compound (D) and a solvent (E). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a negative photosensitive insulating resin composition used for a surface protective film (overcoat film) or an interlayer insulating film (passivation film) such as a semiconductor element and a cured product (insulator) obtained by curing the same. .

  Conventionally, polyimide-based resins having excellent heat resistance and mechanical characteristics have been widely used as surface protective films and interlayer insulating films used for semiconductor elements of electronic devices. In order to improve film formation accuracy by increasing the integration of semiconductor elements, various photosensitive polyimide resins having photosensitivity have been proposed.

  For example, Patent Document 1 describes a composition containing a photosensitive polyimide resin in which a photocrosslinking group is introduced into a polyimide precursor by ionic bonding, and Patent Document 2 describes photocrosslinking by an ester bond to the polyimide precursor. A composition containing a photosensitive polyimide resin having a group introduced therein is described.

  However, these compositions have a drawback that a ring-closing step is required for imidization, and resolution is not sufficient because of solvent development. Patent Document 3 describes a negative photosensitive composition in which a polyfunctional acrylic compound is added to an aromatic polyimide precursor, but the same problems as described above have been pointed out.

  In order to solve such problems, Patent Document 4 discloses a photosensitive insulating resin composition containing an alkali-soluble resin having a phenolic hydroxyl group, a crosslinking agent, crosslinked fine particles, an oxirane ring-containing compound and a photoacid generator. Has been proposed. As the alkali-soluble resin having a phenolic hydroxyl group, cresol novolak resin, polyhydroxystyrene, phenol-xylylene glycol condensation resin, and the like are disclosed, and cresol novolak resin is mainly used.

However, when a cresol novolac resin is used as the main component of the alkali-soluble resin constituting the negative photosensitive resin composition, since there are more reactive points at the time of curing, curing shrinkage occurs when crosslinking proceeds. Sometimes it gets bigger. Patent Document 4 does not suggest any resolution after curing. That is, with the miniaturization of the semiconductor, especially when a resolution of 10 μm or less is required, the pattern may be deformed due to thermal sagging.
Japanese Examined Patent Publication No.59-52822 Japanese Patent Laid-Open No. 3-186847 JP-A-8-50354 JP 2003-215802 A

  The present invention is a surface protective film that is excellent in various properties such as resolution, electrical insulation, thermal shock resistance, chemical resistance and the like, suppresses deformation due to thermal sagging of the pattern, and exhibits low curing shrinkage and low water absorption. Another object is to provide a photosensitive insulating resin composition capable of forming an interlayer insulating film. Another object of the present invention is to provide a cured product (insulating film) obtained by curing such a photosensitive insulating resin composition.

  The present inventors have intensively studied to solve the above problems. As a result, the present inventors have found that the above problems can be solved by using a resin having a specific structure and composition ratio as an alkali-soluble resin having a phenolic hydroxyl group, and further using a specific photoacid generator. It came to be completed.

That is, the negative photosensitive insulating resin composition according to the present invention is
(A1) an alkali-soluble resin having a structural unit represented by the following formula (1):
(A2) an alkali-soluble resin other than the resin (A1),
(B) a photoacid generator,
(C) a compound having a functional group capable of reacting with the resins (A1) and (A2),
(D) It contains an oxirane ring-containing compound and (E) a solvent, and the weight ratio (A1 / A2) between the resin (A1) and the resin (A2) is 5/95 to 25/75. It is characterized by.

(In the formula, R represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom or a hydroxyl group, and m represents an integer of 0 to 3).
The alkali-soluble resin (A1) is at least one selected from the group consisting of phenols, α, α′-dihaloxylene compounds, α, α′-dihydroxyxylene compounds, and α, α′-dialkoxyxylene compounds. A resin obtained by a condensation reaction with a substituted xylene compound is preferred.

  The compound (C) is preferably at least one compound selected from the group consisting of a compound containing an alkyl etherified amino group and a compound containing a formyl group.

The negative photosensitive insulating resin composition of the present invention may further contain a particulate polymer (F) having a glass transition temperature of 0 ° C. or lower and an average particle diameter of 20 to 500 nm.
The cured product according to the present invention is obtained by curing the negative photosensitive insulating resin composition. The electronic component according to the present invention has the cured product.

  When using the negative photosensitive insulating resin composition according to the present invention, it is possible to produce a cured product excellent in properties such as resolution, thermal shock, low curing shrinkage, and low water absorption, It is useful as a permanent film resist such as an interlayer insulating film or a surface protective film of a semiconductor element.

Hereinafter, the negative photosensitive insulating resin composition and the cured product thereof according to the present invention will be described in detail.
[Negative photosensitive insulating resin composition]
The negative photosensitive insulating resin composition of the present invention includes an alkali-soluble resin (A1) having a structural unit represented by the above formula (1) (hereinafter also referred to as “structural unit (1)”), and the resin (A1). ) Other than the alkali-soluble resin (A2) (hereinafter also referred to as “other alkali-soluble resin”), a photoacid generator (B), a compound having a functional group capable of reacting with the resins (A1) and (A2) ( C) (hereinafter also referred to as “curing agent (C)”), an oxirane ring-containing compound (D) and a solvent (E). The negative photosensitive insulating resin composition may further contain a particulate polymer (F) having a glass transition temperature of 0 ° C. or lower and an average particle diameter of 20 to 500 nm, and if necessary, You may contain additives, such as adhesion assistant, a sensitizer, a leveling agent, a filler, a flame retardant.

(A1) Alkali-soluble resin Alkali-soluble resin (A1) used by this invention contains the said structural unit (1), and it is preferable to consist only of this structural unit (1). When the negative photosensitive insulating resin composition of the present invention contains the alkali-soluble resin (A1) having the structural unit (1), a cured product excellent in thermal shock resistance and low water absorption can be obtained.

  The molecular weight of the alkali-soluble resin (A1) is not particularly limited, but the polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography is, for example, 100,000 or less, preferably 2,000 to 50, 000. When Mw is not less than the lower limit, the cured product has good physical properties such as heat resistance and elongation, and when Mw is not more than the upper limit, the copolymer (A1) exhibits good compatibility with other components, and resin. The composition exhibits good patterning properties. In the present invention, Mw and Mn were analyzed using Tosoh GPC columns (G2000HXL: 2, G3000HXL: 1), flow rate: 1.0 mL / min, elution solvent: tetrahydrofuran, column temperature: 40 ° C. The value measured with a differential refractometer using monodisperse polystyrene as a standard.

  The alkali-soluble resin (A1) having the structural unit (1) includes, for example, phenols, an α, α′-dihaloxylene compound, an α, α′-dihydroxyxylene compound, and an α, α′-dialkoxyxylene compound. It can be produced by subjecting at least one substituted xylene compound selected from the group to a condensation reaction in the absence of a catalyst or in the presence of a hydrogen halide catalyst.

  Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, catechol, resorcinol, 2,3-xylenol, 3,4-xylenol, and 3,5-xylenol.

  Examples of the α, α′-dihaloxylene compound include α, α′-dichloro p-xylene, α, α′-dibromo p-xylene, α, α′-dichloro m-xylene, and α, α′-dibromo m-xylene. Etc. Examples of the α, α′-dihydroxyxylene compound include α, α′-dihydroxy p-xylene and α, α′-dihydroxy m-xylene. Examples of the α, α′-dialkoxyxylene compound include 1,4-benzenedimethanol (α, α′-dimethoxy p-xylene), α, α′-dimethoxy m-xylene, and the like.

  When the condensation reaction between the phenol and the substituted xylene compound is performed, it is not always necessary to use a catalyst, but a hydrogen halide such as hydrogen chloride or hydrogen bromide may be used to shorten the reaction time. Moreover, a solvent may be used as necessary, and an inert solvent having a high boiling point such as dimethylformamide and dimethylacetamide can be appropriately selected.

In the above condensation reaction, the phenol is usually 0 with respect to 1 mol of the substituted xylene compound.
. It is used in an amount of 5 to 10 mol, preferably 1.0 to 3.0 mol. The reaction temperature is 50 ° C to 200 ° C, preferably 80 ° C to 150 ° C. The reaction time is appropriately set depending on the desired molecular weight.

  After completion of the reaction, the remaining unreacted phenol and the hydrogen halide produced by the reaction are distilled off. Furthermore, when controlling the molecular weight and molecular weight distribution of the obtained alkali-soluble resin (A1) to an arbitrary range, the low molecular weight component in the alkali-soluble resin (A1) can be separated and removed with a poor solvent or the like.

(A2) Other alkali-soluble resin Other alkali-soluble resin (A2) used in the present invention is an alkali-soluble resin other than the resin (A1), and has a carboxyl group or a phenolic hydroxyl group. Etc. Among these, a polymer having a phenolic hydroxyl group is preferable.

  Although the molecular weight of said other alkali-soluble resin (A2) is not specifically limited, The weight average molecular weight (Mw) of polystyrene conversion measured by the gel permeation chromatography method is 100,000 or less, for example, Preferably it is 1,000- 50,000. When Mw is not less than the above lower limit, developability and mechanical properties are good, and when Mw is not more than the above upper limit, the resin (A2) exhibits good compatibility with other components, and the resin composition has good patterning. Show properties.

  The resin having a carboxyl group is, for example, a radical using a monomer having a carboxyl group such as (meth) acrylic acid or vinylbenzoic acid and another monomer such as (meth) acrylic acid ester or styrene. It can be synthesized by conventional methods such as polymerization.

The resin having a phenolic hydroxyl group can be synthesized by a conventional method using, for example, phenols and formaldehydes.
Examples of the resin having a phenolic hydroxyl group include a phenol / formaldehyde condensed novolak resin, a cresol / formaldehyde condensed novolak resin, a phenol-naphthol / formaldehyde condensed novolak resin, and a hydroxystyrene polymer.

  In the composition of this invention, you may use a phenol compound (a) together with the said resin (A2) as needed. Examples of the phenol compound (a) include 4,4′-dihydroxydiphenylmethane, 4,4′-dihydroxydiphenyl ether, tris (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) -1- Phenylethane, tris (4-hydroxyphenyl) ethane, 1,3-bis [1- (4-hydroxyphenyl) -1-methylethyl] benzene, 1,4-bis [1- (4-hydroxyphenyl) -1 -Methylethyl] benzene, 4,6-bis [1- (4-hydroxyphenyl) -1-methylethyl] -1,3-dihydroxybenzene, 1,1-bis (4-hydroxyphenyl) -1- [4 -{1- (4-hydroxyphenyl) -1-methylethyl} phenyl] ethane, 1,1,2,2-tetra (4-hydro Shifeniru) ethane and the like.

The amount of the phenol compound (a) used is usually 30 parts by weight or less, preferably 5 to 20 parts by weight, in a total amount of 100 parts by weight with the other alkali-soluble resin (A2).
When the molecular weight and molecular weight distribution of the obtained alkali-soluble resin (A2) are controlled to an arbitrary range, the low molecular weight component in the alkali-soluble resin (A2) can be separated and removed with a poor solvent or the like.

  In the negative photosensitive insulating resin composition of the present invention, the weight ratio (A1 / A2) of the alkali-soluble resin (A1) having the structural unit (1) and the other alkali-soluble resin (A2) is 5/95. To 25/75, preferably 10/90 to 25/75. When the weight ratio (A1 / A2) is within the above range, it is preferable because low curing shrinkage and low water absorption, particularly thermal sag during thermal curing can be suppressed and high resolution can be maintained even after thermal curing.

  In the composition of the present invention, the total amount of the alkali-soluble resin (A1) and the other alkali-soluble resin (A2) is usually 1 to 40% by weight based on the entire composition (including the solvent (E)), Preferably it is 5-35 weight%. When the total amount of the alkali-soluble resin (A1) and the other alkali-soluble resin (A2) is within the above range, the handleability of the composition is good, and a cured product can be easily formed.

(B) Photoacid generator Photoacid generator (B) used in the present invention includes onium salt compounds, halogen-containing compounds, diazoketone compounds, sulfone compounds, sulfonic acid compounds, sulfonimide compounds, diazomethane compounds, and the like. Can do.

  Examples of the onium salt compounds include iodonium salts, sulfonium salts, phosphonium salts, diazonium salts, pyridinium salts, and the like. Specifically, diphenyliodonium trifluoromethanesulfonate, diphenyliodonium p-toluenesulfonate, diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluorophosphate, diphenyliodonium tetrafluoroborate, triphenylsulfonium trifluorochlorosulfonate, triphenylsulfonium p- Toluenesulfonate, triphenylsulfonium hexafluoroantimonate, 4-t-butylphenyl diphenylsulfonium trifluoromethanesulfonate, 4-t-butylphenyl diphenylsulfonium p-toluenesulfonate, 1- (4,7-dibutoxy-1-naphthalenyl ) Tetrahydrothiophenium trifluoromethanesulfo Over DOO, 4,7-di -n- butoxy naphthyl tetrahydrothiophenium trifluoromethanesulfonate, and the like.

  Examples of the halogen-containing compound include haloalkyl group-containing hydrocarbon compounds and haloalkyl group-containing heterocyclic compounds. Specifically, 1,10-dibromo-n-decane, 1,1-bis (4-chlorophenyl) -2,2,2-trichloroethane, phenyl-bis (trichloromethyl) -1,3,5-triazine, 4-methoxyphenyl-bis (trichloromethyl) -1,3,5-triazine, styryl-bis (trichloromethyl) -1,3,5-triazine, naphthyl-bis (trichloromethyl) -1,3,5-triazine 2,4-trichloromethyl (piperonyl) -1,3,5-triazine, 2- (1,3-benzodioxol-5-yl) -4,6-bis (trichloromethyl) -1,3 Examples thereof include s-triazine derivatives such as 5-triazine.

  Examples of the diazoketone compound include 1,3-diketo-2-diazo compounds, diazobenzoquinone compounds, diazonaphthoquinone compounds, and the like. Specific examples include 1,2-naphthoquinonediazide-4-sulfonic acid ester compounds of phenols.

  Examples of the sulfone compounds include β-ketosulfone compounds, β-sulfonylsulfone compounds, and α-diazo compounds of these compounds. Specific examples include 4-trisphenacylsulfone, mesitylphenacylsulfone, bis (phenacylsulfonyl) methane, and the like.

  Examples of the sulfonic acid compound include alkyl sulfonic acid esters, haloalkyl sulfonic acid esters, aryl sulfonic acid esters, and imino sulfonates. Specific examples include benzoin tosylate, pyrogallol tris trifluoromethane sulfonate, o-nitrobenzyl trifluoromethane sulfonate, o-nitrobenzyl p-toluene sulfonate, and the like.

  Examples of the sulfonimide compound include N- (trifluoromethylsulfonyloxy) succinimide, N- (trifluoromethylsulfonyloxy) phthalimide, N- (trifluoromethylsulfonyloxy) diphenylmaleimide, N- (trifluoromethylsulfonyl). And (oxy) bicyclo [2.2.1] hept-5-ene-2,3-dicarboximide, N- (trifluoromethylsulfonyloxy) naphthylimide, and the like.

  Examples of the diazomethane compound include bis (trifluoromethylsulfonyl) diazomethane, bis (cyclohexylsulfonyl) diazomethane, and bis (phenylsulfonyl) diazomethane.

  By the catalytic action of the acid generated from the photoacid generator (B), the functional group in the curing agent (C) reacts with the alkali-soluble resin (A1) with dealcoholization to form a negative pattern. can do.

Among the photoacid generators (B), phenyl-bis (trichloromethyl) -s-triazine, 4-methoxyphenyl-bis (trichloromethyl) -s-triazine, styryl-bis (trichloromethyl) -s-triazine 4-methoxystyryl-bis (trichloromethyl) -s-triazine, naphthyl-bis (trichloromethyl) -s-triazine, 2- [2- (5-methylfuran-2-yl) ethynyl] -4,6- Compounds having a triazine structure such as bis (trichloromethyl) -s-triazine and 2,4-trichloromethyl (piperonyl) -s-triazine are preferable, and 4-methoxystyryl-bis (trichloromethyl) -s-triazine, 2 -[2- (5-methylfuran-2-yl) ethynyl] -4,6-bis (trichloromethyl) -s-triazine, 2, - trichloromethyl (piperonyl) -s-triazine is preferred in terms of solubility and high sensitivity to solvents.

  By using the photoacid generator (B) having the triazine structure as described above, the amount of addition can be reduced as compared with other photoacid generators, for example, onium salt photoacid generators. The reliability (reliability) can be improved, and the water absorption rate of the cured product can be lowered.

  The photoacid generator (B) may be used alone or in combination of two or more. Moreover, the compounding quantity of the said photo-acid generator (B) is the said alkali-soluble resin (A1) and other alkali-soluble resin (A2) from a viewpoint of ensuring the sensitivity, resolution, pattern shape, etc. of the resin composition of this invention. ) And phenol compound (a) in a total amount of 100 parts by weight, 0.1 to 10 parts by weight, preferably 0.3 to 5 parts by weight, particularly preferably 0.3 to 2.5 parts by weight. In this case, if the blending amount of the photoacid generator (B) is less than 0.1 parts by weight, curing may be insufficient and heat resistance may be reduced. If it exceeds 10 parts by weight, transparency to radiation is reduced. However, the pattern shape may be deteriorated.

(C) Curing Agent The curing agent (C) used in the present invention is a compound having a functional group capable of reacting with the alkali-soluble resin (A1) and the other alkali-soluble resin (A2). Such curing agents (
Examples of C) include a compound containing an alkyl etherified amino group (hereinafter also referred to as “alkyl etherified amino group-containing compound”) and a compound containing a formyl group (hereinafter also referred to as “formyl group-containing compound”). Etc.).

  The alkyl etherified amino group-containing compound is not particularly limited as long as it is a compound containing at least two alkyl etherified amino groups in the molecule. Here, the alkyl etherified amino group is, for example, a group represented by the following formula.

—NHR ¹¹ —O—R ¹²
In the formula, R ¹¹ represents an alkylene group (a divalent hydrocarbon group), and R ¹² represents an alkyl group.
Examples of such alkyl ether amino group-containing compounds include active methylol groups (CH ₂ ) in nitrogen compounds such as (poly) methylol melamine, (poly) methylol glycoluril, (poly) methylol benzoguanamine, and (poly) methylol urea. Examples thereof include compounds in which all or part (however, at least two) of (OH groups) are alkyl etherified.

  The alkyl group constituting the alkyl ether is a methyl group, an ethyl group or a butyl group, and the alkyl groups constituting the alkyl ether contained in the alkyl etherified amino group-containing compound are the same as each other. May be different. Further, a methylol group that is not alkyletherified may be self-condensed within one molecule or may be condensed between two molecules, resulting in the formation of an oligomer component.

  Examples of such alkyl ether amino group-containing compounds include hexamethoxymethyl melamine, hexabutoxymethyl melamine, tetramethoxymethyl glycoluril, tetrabutoxymethyl glycoluril and the like.

  The formyl group-containing compound is not particularly limited as long as it is a compound containing a formyl group in the molecule. Specific examples include benzaldehyde, hydroxybenzaldehyde, phthalaldehyde, acetaldehyde, butyraldehyde, glyoxal, and brutal aldehyde.

  The said hardening | curing agent (C) may be used individually by 1 type, or may be used in combination of 2 or more type. Moreover, the compounding quantity of the said hardening | curing agent (C) is 1-100 weight part normally with respect to 100 weight part of total amounts of alkali-soluble resin (A1), another alkali-soluble resin (A2), and a phenol compound (a). The amount is preferably 5 to 50 parts by weight. When the blending amount is equal to or higher than the lower limit, a cured product that is sufficiently cured and exhibits good electrical insulation is obtained, and when it is equal to or lower than the upper limit, a cured product that exhibits good patterning characteristics and heat resistance is obtained.

(D) Oxirane ring-containing compound The oxirane ring-containing compound (D) used in the present invention is not particularly limited as long as it contains an oxirane ring in the molecule. Specifically, phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol type epoxy resin, trisphenol type epoxy resin, tetraphenol type epoxy resin, phenol-xylylene type epoxy resin, naphthol-xylylene type epoxy resin, phenol- Examples thereof include naphthol type epoxy resins, phenol-dicyclopentadiene type epoxy resins, alicyclic epoxy resins, and aliphatic epoxy resins. Among these, an epoxy compound having a softening point of 30 ° C. or lower is preferable in terms of resolution. Examples of the epoxy compound having a softening point of 30 ° C. or lower include trimethylolpropane glycidyl ether, phenol novolac type epoxy resin, and bisphenol type epoxy resin.

  The amount of the oxirane ring-containing compound (D) is 1 to 70 parts by weight based on 100 parts by weight of the total amount of the alkali-soluble resin (A1), the other alkali-soluble resin (A2) and the phenol compound (a). The amount is preferably 3 to 30 parts by weight. If the blending amount is less than 1 part by weight, the chemical resistance of the resulting cured film may be lowered, and if it exceeds 70 parts by weight, the resolution may be lowered.

(E) Solvent The solvent (E) is added to improve the handleability of the resin composition and to adjust the viscosity and storage stability. The type of the solvent (E) is not particularly limited, and examples thereof include ethylene glycol monoalkyl ether acetates such as ethylene glycol monomethyl ether acetate and ethylene glycol monoethyl ether acetate;
Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether;
Propylene glycol dialkyl ethers such as propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, propylene glycol dibutyl ether;
Propylene glycol monoalkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate;
Cellosolves such as ethyl cellosolve and butyl cellosolve;
Carbitols such as butyl carbitol;
Lactic acid esters such as methyl lactate, ethyl lactate, n-propyl lactate and isopropyl lactate;
Aliphatic carboxylic acid esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, isoamyl acetate, isopropyl propionate, n-butyl propionate, isobutyl propionate;
Other esters such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate;
Aromatic hydrocarbons such as toluene and xylene;
Ketones such as 2-heptanone, 3-heptanone, 4-heptanone, cyclohexanone;
N-dimethylformamide, N-methylacetamide, N, N-dimethylacetamide,
Amides such as N-methylpyrrolidone;
and lactones such as γ-butyrolacun.

  The said solvent (E) may be used individually by 1 type, or 2 or more types may be mixed and used for it. The amount of the solvent (E) is appropriately selected according to the use of the composition and the coating method, and is not particularly limited as long as the composition can be made uniform. The amount is -90% by weight, preferably 30-85% by weight, more preferably 40-80% by weight.

(F) Particulate Polymer The particulate polymer (F) used as necessary in the present invention has a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of 0 ° C. or less and an average particle size of 20 ~ 500 nm.

The particulate polymer (F) is not particularly limited as long as it has the above physical properties, but a crosslinkable monomer having two or more unsaturated polymerizable groups (hereinafter also simply referred to as “crosslinkable monomer”), One or more other monomers (hereinafter simply referred to as “other monomer (f)”) that can be copolymerized with the crosslinkable monomer and are selected so that the Tg of the particulate polymer (F) is 0 ° C. or lower. And a copolymer thereof is preferred. In particular, the other monomer (f) is preferably a copolymer using a monomer having 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 isocyanate group, or a hydroxyl group.

  Examples of the crosslinkable monomer include divinylbenzene, diallyl phthalate, ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and polyethylene glycol. Examples include compounds having a plurality of polymerizable unsaturated groups such as di (meth) acrylate and polypropylene glycol di (meth) acrylate. Of these, divinylbenzene is preferable.

Examples of the other monomer (f) include:
Butadiene, isoprene, dimethylbutadiene, chloroprene, 1,3-pentadiene, (meth) acrylonitrile, α-chloroacrylonitrile, α-chloromethylacrylonitrile, α-methoxyacrylonitrile, α-ethoxyacrylonitrile, crotonate nitrile, cinnamic nitrile, Unsaturated nitrile compounds such as itaconic acid dinitrile, maleic acid dinitrile, fumarate dinitrile;
(Meth) acrylamide, N, N′-methylenebis (meth) acrylamide, N, N′-ethylenebis (meth) acrylamide, N, N′-hexamethylenebis (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, Unsaturated amides such as N- (2-hydroxyethyl) (meth) acrylamide, N, N-bis (2-hydroxyethyl) (meth) acrylamide, crotonic acid amide, cinnamic acid amide;
Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, lauryl (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene (Meth) acrylic acid esters such as glycol (meth) acrylate;
Aromatic vinyl compounds such as styrene, α-methylstyrene, o-methoxystyrene, p-hydroxystyrene, p-isopropenylphenol;
Epoxy (meth) acrylates obtained by reaction of diglycidyl ether of bisphenol A, diglycidyl ether of glycol and the like with (meth) acrylic acid, hydroxyalkyl (meth) acrylate, etc .;
Urethane (meth) acrylates obtained by reaction of hydroxyalkyl (meth) acrylates with polyisocyanates;
Epoxy group-containing unsaturated compounds such as glycidyl (meth) acrylate and (meth) allyl glycidyl ether;
(Meth) acrylic acid, itaconic acid, succinic acid-β- (meth) acryloxyethyl, maleic acid-β- (meth) acryloxyethyl, phthalic acid-β- (meth) acryloxyethyl, hexahydrophthalic acid- unsaturated acid compounds such as β- (meth) acryloxyethyl;
Amino group-containing unsaturated compounds such as dimethylamino (meth) acrylate and diethylamino (meth) acrylate;
Amide group-containing unsaturated compounds such as (meth) acrylamide and dimethyl (meth) acrylamide;
Examples thereof include hydroxyl group-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, hydroxyalkyl (Meth) acrylates and the like are preferable, and butadiene is particularly preferable.

  The content ratio of the crosslinkable monomer and the other monomer (f) constituting the particulate polymer (F) is 1 to 20% by weight of the crosslinkable monomer and the other monomer (f) with respect to the total monomers used for copolymerization. It is desirable to use 80 to 99% by weight, preferably 2 to 10% by weight of the crosslinkable monomer and 90 to 98% by weight of the other monomer (f).

  When the particulate polymer (F) is obtained by copolymerization of the crosslinkable monomer and the other monomer (f) within the above range, rubber-like soft fine particles are formed. Can be prevented, and a cured film having excellent durability can be obtained.

  The average particle diameter of the particulate polymer (F) is 20 to 500 nm, preferably 40 to 200 nm, more preferably 50 to 120 nm. The particle diameter control method of the particulate polymer (F) is not particularly limited. For example, when the particulate polymer (F) is synthesized by emulsion polymerization, a method of controlling the particle size by controlling the number of micelles during emulsion polymerization according to the amount of the emulsifier used can be exemplified.

  The amount of the particulate polymer (F) is preferably 1 to 50 weights with respect to 100 parts by weight of the total amount of the alkali-soluble resin (A), the other alkali-soluble resin (A2) and the phenol compound (a). Part. When the blending amount is in the above range, the particulate polymer (F) exhibits good compatibility (dispersibility) with other components, and the resulting cured film has good thermal shock resistance and heat resistance.

In the photosensitive resin composition of the present invention, as other additives, for example, an adhesion assistant, a leveling agent, a dye and the like can be contained.
<Method for preparing photosensitive insulating resin composition>
The negative photosensitive insulating resin composition of the present invention can be prepared by dispersing and mixing a predetermined amount of each of the above components using a disperser such as an agitator, a dissolver, a homogenizer, or a three roll mill. Moreover, you may filter using a mesh membrane filter etc. as needed.

[Cured product]
The negative photosensitive insulating resin composition according to the present invention is excellent in resolution, and the cured product is excellent in thermal shock resistance, low curing shrinkage, low water absorption, and the like. Therefore, the negative photosensitive insulating resin composition of the present invention can be suitably used particularly as a material for a surface protective film or an interlayer insulating film of a semiconductor element.

The cured product according to the present invention is formed by curing the photosensitive insulating resin composition. Specifically, a cured product can be formed as follows.
The negative photosensitive insulating resin composition is applied to a support (copper foil with resin, copper-clad laminate, silicon wafer with a metal sputtered film, alumina substrate, etc.), and the solvent is volatilized by drying. Form a coating film. Thereafter, exposure is performed through a desired mask pattern, heat treatment (hereinafter, this heat treatment is referred to as “PEB”), an alkali-soluble resin (A1), another alkali-soluble resin (A2), and a curing agent (C ). Subsequently, it develops with an alkaline developing solution, A desired pattern can be obtained by melt | dissolving and removing an unexposed part. Furthermore, a cured film can be obtained by performing a heat treatment to develop the insulating film characteristics.

Examples of the method for coating the resin composition on the support include coating methods such as dipping, spraying, bar coating, roll coating, spin coating, and curtain coating. The coating thickness can be appropriately controlled by adjusting the coating means and the solid content concentration and viscosity of the composition solution.

Examples of the radiation used for exposure include ultraviolet rays such as a low-pressure mercury lamp, a high-pressure mercury lamp, a metal halide lamp, a g-line stepper, and an i-line stepper, an electron beam, and a laser beam. The exposure amount is appropriately selected depending on the light source used, the resin film thickness, and the like. For example, in the case of ultraviolet irradiation from a high-pressure mercury lamp, if the resin film thickness is 1 to 50 μm, 1,000 to 20,000 J / m ^2. Degree.

  After the exposure, PEB treatment is performed to promote the curing reaction between the alkali-soluble resin (A1) and other alkali-soluble resin (A2) and the curing agent (C) by the generated acid. The conditions vary depending on the blending amount of the resin composition and the film thickness used, but are usually 70 to 150 ° C., preferably 80 to 120 ° C., and about 1 to 60 minutes. Thereafter, development is performed with an alkaline developer, and a desired pattern is formed by dissolving and removing unexposed portions. Examples of the developing method in this case include a shower developing method, a spray developing method, an immersion developing method, a paddle developing method, and the like. The developing conditions are usually 20 to 40 ° C. for about 1 to 10 minutes.

  Examples of the alkaline developer include an alkaline aqueous solution in which an alkaline compound such as sodium hydroxide, potassium hydroxide, ammonia water, tetramethylammonium hydroxide, and choline is dissolved in water so as to have a concentration of about 1 to 10% by weight. Can be mentioned. An appropriate amount of a water-soluble organic solvent such as methanol or ethanol, a surfactant, or the like can be added to the alkaline aqueous solution. In addition, after developing with an alkaline developer, it is washed with water and dried.

  Furthermore, in order to sufficiently develop the characteristics as an insulating film after development, the film can be sufficiently cured by heat treatment. Such curing conditions are not particularly limited, but the composition can be cured by heating at a temperature of 50 to 250 ° C. for about 30 minutes to 10 hours depending on the use of the cured product. Moreover, in order to fully advance hardening and to prevent the deformation | transformation of the obtained pattern shape, it can also heat in two steps. For example, in the first stage, heating can be performed at a temperature of 50 to 120 ° C. for about 5 minutes to 2 hours, and further heating at a temperature of 80 to 250 ° C. for about 10 minutes to 10 hours for curing. Under such curing conditions, a general oven, an infrared furnace, or the like can be used as heating equipment.

[Electronic parts]
The electronic component according to the present invention has the above-described cured product of the present invention. Although it does not specifically limit as said electronic component, For example, a semiconductor element (board | substrate with a circuit), a package board | substrate, a printed wiring board, etc. are mentioned.

  For example, as shown in FIGS. 1 and 2, such a semiconductor element has a pattern shape on a substrate 1 such as a silicon wafer having a metal wiring pattern 2 and a surface of the substrate 1 having the metal wiring pattern 2. On the uppermost layer of the semiconductor element material 5 having at least one layer having an insulating film 3 having a groove and a metal wiring pattern 4 formed by filling the groove with a metal material, the negative photosensitive insulating resin is formed. The insulating film 6 is formed by curing the composition.

  When a plurality of layers having the insulating film 3 and the metal wiring pattern 4 are present, the insulating film 3 constituting each layer may be formed using the same insulating resin composition, or different insulating resin compositions may be used. It may be formed using. Moreover, the metal wiring pattern 4 of each layer may be formed using the same metal material, or may be formed using different metal materials. The insulating film 6 can be formed in a pattern by applying the method for forming the cured product (cured film).

[Example]
EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these Examples at all. In addition, the part in a following example etc. means a weight part unless there is particular notice. Moreover, about each characteristic of hardened | cured material, it evaluated by the following method.

(1) Resolution (after development)
A photosensitive insulating resin composition was spin-coated on a 6-inch silicon wafer and heated at 110 ° C. for 3 minutes using a hot plate to form a uniform coating film having a thickness of 15 μm. Thereafter, using an i-line stepper (NSR-2205i12D manufactured by Nikon Corporation), exposure was performed through the pattern mask so that the exposure amount was 10,000 J / m ² . Subsequently, it heated at 110 degreeC for 3 minute (s), and was immersion-developed for 2 minutes at 23 degreeC using the 2.38 mass% tetramethylammonium hydroxide aqueous solution. The minimum dimension of the obtained pattern was defined as the resolution (after development).

(2) Resolution (after curing)
The substrate was heated in a convection clean oven at 190 ° C. for 1 hour, and the minimum dimension of the obtained pattern was defined as resolution (after curing).

(3) Thermal shock property A photosensitive insulating resin composition is applied to a thermal shock property evaluation base material 13 having a patterned copper foil 11 on a substrate 12 as shown in FIG. 3 and FIG. The resultant was heated at 110 ° C. for 3 minutes to form a resin coating film having a thickness of 15 μm on the copper foil 11. Thereafter, the aligner was used to expose the ultraviolet ray from the high pressure mercury lamp so that the exposure amount at a wavelength of 350 nm was 10,000 J / m ² . Next, heat on a hot plate at 110 ° C for 3 minutes (PEB)
Then, the resin coating film was cured by heating at 190 ° C. for 1 hour in a convection oven to obtain a substrate having a cured film. With respect to this base material, a resistance test was conducted by using a thermal shock tester (manufactured by Tabai Espec Co., Ltd.) as a cycle of −55 ° C./30 minutes to 150 ° C./30 minutes. The number of cycles until a defect such as a crack occurred in the cured film was confirmed every 100 cycles.

(4) Curing Shrinkage The photosensitive insulating resin composition was applied to an 8-inch silicon wafer and heated at 110 ° C. for 3 minutes using a hot plate to form a 15 μm thick resin coating film. Thereafter, the aligner was used to expose the ultraviolet ray from the high pressure mercury lamp so that the exposure amount at a wavelength of 350 nm was 10,000 J / m ² . Subsequently, it heated at 110 degreeC for 3 minute (PEB) with the hotplate, and heated at 190 degreeC for 1 hour in the convection oven, and cured the resin coating film, and obtained the cured film. The film thickness before and after curing was measured for this cured film, and the curing shrinkage was determined from the following formula.

Curing shrinkage (%) = (X−Y) / X × 100
X: Film thickness before curing, Y: Film thickness after curing (5) Water absorption rate A photosensitive insulating resin composition was applied using a 6-inch silicon wafer whose mass was measured in advance as a base material, and 110 using a hot plate. Heating was performed at 0 ° C. for 3 minutes to form a 15 μm thick resin coating film. Thereafter, the aligner was used to expose the ultraviolet ray from the high pressure mercury lamp so that the exposure amount at a wavelength of 350 nm was 10,000 J / m ² . Then 110 ° C on a hot plate
The substrate was heated for 3 minutes (PEB) and heated in a convection oven at 190 ° C. for 1 hour to cure the resin coating and obtain a substrate having a cured film. After measuring the mass of the substrate having the cured film, it was immersed in pure water and left at 23 ° C. for 24 hours. The mass of the base material having the cured film before and after being immersed in pure water was measured, and the water absorption was determined by the following formula.

Water absorption (%) = (B−A) / A × 100
A: Mass of cured film before immersion, B: Mass of cured film after immersion (mass of cured film) = (mass of substrate having cured film)-(mass of substrate)
<Synthesis Example 1>
Phenol and 1,4-benzenedimethanol were mixed at a molar ratio of 100: 120, and this mixture was dissolved in propylene glycol monomethyl ether. This mixed solution was condensed by a conventional method using a p-toluenesulfonic acid catalyst to obtain an alkali-soluble resin (A1-1) having a polystyrene-equivalent weight average molecular weight of 5500.

<Synthesis Example 2>
m-cresol and 1,4-benzenedimethanol were mixed at a molar ratio of 100: 120, and the mixture was dissolved in propylene glycol monomethyl ether. This mixed solution was condensed by a conventional method using a p-toluenesulfonic acid catalyst to obtain an alkali-soluble resin (A1-2) having a polystyrene-reduced weight average molecular weight of 5500.

<Synthesis Example 3>
m-cresol and p-cresol are mixed at a molar ratio of 80:20, formalin is added to the mixture, and the mixture is condensed by an ordinary method using an oxalic acid catalyst, and the weight average molecular weight in terms of polystyrene is 6,800. Of cresol novolac resin (hereinafter referred to as “phenol resin (A2-1)”).

[Examples 1 to 4]
The types and amounts of alkali-soluble resins (A1), other alkali-soluble resins (A2), photoacid generators (B), curing agents (C), oxirane ring-containing compounds (D) and particulate polymers (shown in Table 1) F) was dissolved in the solvent (E) to prepare a negative photosensitive insulating resin composition. Using this resin composition, a cured film was produced according to the method described in the above evaluation method. The properties of the resin composition and the cured film were measured according to the above evaluation methods. The results are shown in Table 2.

[Comparative Examples 1-2]
A resin composition comprising the components shown in Table 1 and a cured film thereof were prepared in the same manner as in Example 1. The characteristics of the resin composition and its cured film were measured in the same manner as in Example 1. The results are shown in Table 2.

Each component shown in Table 1 is as follows.
<Alkali-soluble resin (A1)>
Polystyrene equivalent weight average molecular weight (Mw) = 5,500
A1-2: a resin comprising m-cresol and 1,4-benzenedimethanol,
Polystyrene equivalent weight average molecular weight (Mw) = 5,500
<Other alkali-soluble resin (A2)>
A2-1: novolak resin of m-cresol / p-cresol = 80/20 (molar ratio),
Polystyrene equivalent weight average molecular weight (Mw) = 6,800
A2-2: p-hydroxystyrene / styrene = 80/20 (molar ratio) copolymer,
Polystyrene equivalent weight average molecular weight (Mw) = 10,000
<Acid generator (B)>
B-1: 4-methoxystyryl-bis (trichloromethyl) -s-triazine (manufactured by Nippon Siebel Hegner Co., Ltd., trade name: Triazine PMS)
B-2: 2- [2- (5-methylfuran-2-yl) ethynyl] -4,6-bis (trichloromethyl) -s-triazine (manufactured by Sanwa Chemical Co., Ltd., trade name: TME-triazine)
B-3: 4,7-di-n-butoxynaphthyltetrahydrothiophenium trifluoromethanesulfonate <curing agent (C)>
C-1: Hexamethoxymethylmelamine (Mitsui Cytec Co., Ltd., trade name: Cymel 300)
<Oxirane ring-containing compound (D)>
D-1: Trimethylolpropane glycidyl ether, liquid, softening point = 30 ° C. or less <Solvent (E)>
E-1: Ethyl lactate E-2: 2-heptanone <Particulate polymer (F)>
F-1: butadiene / hydroxybutyl methacrylate / methacrylic acid / divinylbenzene = 55/37/6/2 (% by weight), average particle size = 75 nm, Tg = −10 ° C.
F-2: butadiene / styrene / hydroxybutyl methacrylate / methacrylic acid / divinylbenzene = 48/24/20/6/2 (% by weight), average particle size = 70 nm, Tg = −35 ° C.

It is sectional drawing which shows an example of the semiconductor element which has the hardened | cured material of this invention. It is sectional drawing which shows an example of the semiconductor element which has the hardened | cured material of this invention. It is sectional drawing of the base material for thermal-impact evaluation. It is a top view of the base material for thermal shock evaluation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Board | substrate 2, 4 Metal wiring 3 Insulating film 5 Semiconductor element material 6 Insulating film which consists of positive type photosensitive insulating resin composition concerning this invention 11 Copper foil 12 Substrate 13 Base material

Claims (7)

(A1) an alkali-soluble resin having a structural unit represented by the following formula (1):
(A2) an alkali-soluble resin other than the resin (A1),
(B) a photoacid generator,
(D) It contains an oxirane ring-containing compound and (E) a solvent, and the weight ratio (A1 / A2) between the resin (A1) and the resin (A2) is 5/95 to 25/75. A negative photosensitive insulating resin composition characterized by the above.

(In the formula, R represents an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, a halogen atom or a hydroxyl group, and m represents an integer of 0 to 3).   The alkali-soluble resin (A1) is at least one selected from the group consisting of phenols, α, α′-dihaloxylene compounds, α, α′-dihydroxyxylene compounds, and α, α′-dialkoxyxylene compounds. The negative photosensitive insulating resin composition according to claim 1, which is a resin obtained by a condensation reaction with a substituted xylene compound.   The negative photosensitive insulating resin composition according to claim 1, wherein the photoacid generator (B) is a compound having a triazine structure.   2. The negative according to claim 1, wherein the compound (C) is at least one compound selected from the group consisting of a compound containing an alkyl etherified amino group and a compound containing a formyl group. Type photosensitive insulating resin composition.   The negative photosensitive insulating resin composition according to claim 1, further comprising a particulate polymer (F) having a glass transition temperature of 0 ° C or lower and an average particle diameter of 20 to 500 nm.   Hardened | cured material obtained by hardening | curing the negative photosensitive insulating resin composition in any one of Claims 1-5.   An electronic component having the cured product according to claim 6.

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