JP6636599B2 - Epoxy resin composition, prepreg and metal-clad laminate, printed wiring board - Google Patents

Description

  The present invention relates to an epoxy resin composition that gives a cured product having excellent heat resistance and water resistance, a prepreg impregnated with a fiber base material, a metal-clad laminate, a printed wiring board, and a semiconductor device.

  Epoxy resin compositions are widely used in the fields of electrical and electronic parts, structural materials, adhesives, paints, etc. due to workability and excellent electrical properties, heat resistance, adhesiveness, moisture resistance (water resistance), etc. of the cured product. Have been.

  However, in recent years, in the electric and electronic fields, along with its development, the resin composition has been highly purified, as well as moisture resistance, adhesion, dielectric properties, viscosity reduction for highly filling a filler (inorganic or organic filler), Further improvements in various properties such as increased reactivity for shortening the molding cycle are required. As structural materials, lightweight materials having excellent mechanical properties are required for aerospace materials, leisure and sports equipment applications, and the like. In particular, in the field of semiconductor encapsulation and in the substrate (the substrate itself or its peripheral material), the required characteristics thereof are becoming higher year by year. For example, a higher Tg of the peripheral material due to an increase in the driving temperature of the semiconductor is required. I have.

Generally, when the Tg of an epoxy resin is increased, the water absorption rate increases (Non-Patent Document 1). This is due to the effect of improving the crosslink density. However, with the demand for high Tg in semiconductor peripheral materials that require low moisture absorption, development of resins having these contradictory characteristics has been urgently required.
On the other hand, Patent Literature 1 discloses a phenol novolak resin having a biphenyl skeleton and a phenol novolak-type epoxy resin obtained by epoxidizing the phenol novolak resin, and describes its utility for semiconductor encapsulant applications.
However, although this epoxy resin achieves both high heat resistance and flame retardancy in combination with a phenolic resin, it has a high water absorption and has a problem in using it for electronic materials that require extremely high reliability.
In addition, there is no description about the properties of the composition containing these epoxy resin and the amine-based curing agent, and there is no description about the usefulness of the composition for use in a printed wiring board.

JP 2013-43958 A

Ogura Ichiro, "Relationship between Chemical Structure and Properties of Epoxy Resin", DIC Technical Review No. 7, Japan, 2001, 7 pages

  The present invention has been made as a result of studies to solve such problems, and provides an epoxy resin composition whose cured product has high heat resistance, low water absorption and low dielectric constant.

（式中、（ａ）（ｂ）の比率は（ａ）／（ｂ）=１〜３である。Ｇはグリシジル基を表す。ｎは繰り返し数であり、０〜５である。）で表されるエポキシ樹脂と二官能以上のアミン系硬化剤を必須成分とするエポキシ樹脂組成物、
（２）
前項（１）に記載のエポキシ樹脂組成物を繊維基材に含浸してなるプリプレグ、
（３）
前記繊維素材がガラス繊維基材である前項（２）に記載のプリプレグ、
（４）
前記ガラス繊維基材がＴガラス、Ｓガラス、Ｅガラス、ＮＥガラス、および石英ガラスからなる群から選ばれる少なくとも一種を含む、前項（２）又は（３）のいずれか一項に記載のプリプレグ、
（５）
前項（２）及至（４）に記載のプリプレグの少なくとも一方の面に金属箔が積層された、金属張積層板、
（６）
前項（１）に記載のエポキシ樹脂組成物からなる絶縁層をフィルム上に、又は金属箔上に形成してなる樹脂シート、
（７）
前項（５）に記載の金属張積層板を回路基板に用いてなるプリント配線基板、
（８）
前項（２）及至（４）のいずれか一項に記載のプリプレグ、及び／又は前項（６）に記載の樹脂シートを硬化してなるプリント配線基板、
（９）
前項（７）又は（８）のいずれか一項に記載のプリント配線基板に半導体素子を搭載してなる半導体装置、
を提供するものである。 The present inventors have conducted intensive studies to solve the above problems, and as a result, have completed the present invention.
That is, the present invention provides (1) the following general formula (1)

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.) Epoxy resin composition containing an epoxy resin and a bifunctional or higher amine-based curing agent as essential components,
(2)
A prepreg obtained by impregnating a fiber base material with the epoxy resin composition according to the above (1);
(3)
The prepreg according to the above (2), wherein the fiber material is a glass fiber base material,
(4)
The prepreg according to any one of the above (2) or (3), wherein the glass fiber substrate includes at least one selected from the group consisting of T glass, S glass, E glass, NE glass, and quartz glass.
(5)
A metal-clad laminate, wherein a metal foil is laminated on at least one surface of the prepreg according to the above (2) to (4).
(6)
A resin sheet formed by forming an insulating layer comprising the epoxy resin composition according to the above (1) on a film or a metal foil;
(7)
A printed wiring board using the metal-clad laminate according to (5) above as a circuit board,
(8)
A prepreg according to any one of (2) to (4), and / or a printed wiring board obtained by curing the resin sheet according to (6);
(9)
A semiconductor device having a semiconductor element mounted on the printed wiring board according to any one of the above (7) or (8),
Is provided.

  The epoxy resin composition of the present invention provides a cured product capable of simultaneously achieving high heat resistance and water resistance in the cured product thereof, and is extremely useful for producing a laminated board such as a printed wiring board or a build-up board. Material.

（式中、（ａ）（ｂ）の比率は（ａ）／（ｂ）=１〜３である。Ｇはグリシジル基を表す。ｎは繰り返し数であり、０〜５である。） Hereinafter, the epoxy resin composition of the present invention will be described.
The epoxy resin composition of the present invention contains, as essential components, a compound represented by the following formula (1) (hereinafter, referred to as the epoxy resin of the present invention) and a difunctional or higher functional amine curing agent as the epoxy resin.

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.)

Epoxy resin used in the present invention can be synthesized by the method described in JP-A-2011-252037, JP-A-2008-156553, JP-A-2013-043958, International Publication WO2012 / 053522, WO2007 / 007827. Any method may be used as long as it has the structure of the formula (1).
However, in the present invention, it is particularly preferable to use a compound in which the ratio (polyfunctionalization ratio) of the formula (a) and the formula (b) is (a) / (b) = 1 to 3. When the structure (a) has many structures, the heat resistance is increased, but not only does the water absorbing property deteriorate, but also the structure becomes brittle and hard. Therefore, a polyfunctionalization ratio within the above range is preferable.

  The softening point (ring and ball method) of the epoxy resin used is preferably from 50 to 150 ° C, more preferably from 52 to 100 ° C, particularly preferably from 52 to 95 ° C. If the temperature is lower than 50 ° C., stickiness is severe, handling is difficult, and there is a problem in productivity. On the other hand, when the temperature is 150 ° C. or higher, the temperature is close to the molding temperature, and the fluidity during molding cannot be ensured.

  The epoxy equivalent of the epoxy resin used is 180 to 350 g / eq. It is preferred that In particular, 190 to 300 g / eq. It is. When the epoxy equivalent is 180 g / eq. In the case of cutting, since the number of functional groups is too large, the cured product after curing tends to have a high water absorption and to be brittle. When the epoxy equivalent is 350 g / eq. When it exceeds, it is considered that the softening point becomes very large or the epoxidation does not progress cleanly, so that the chlorine amount becomes extremely large, which is not preferable.

  The chlorine content of the epoxy resin used in the present invention is 200 to 1500 ppm by total chlorine (hydrolysis method), and particularly preferably 200 to 900 ppm. According to the JPCA standard, it is desired that even epoxy alone does not exceed 900 ppm. Further, a large amount of chlorine is not preferable because the electric reliability is affected accordingly. If the amount is less than 200 ppm, an excessive purification step is required, which causes a problem in productivity, which is not preferable.

  The epoxy resin used in the present invention has a melt viscosity at 150 ° C. of 0.05 to 5 Pa · s. In particular, it is 0.05 to 2.0 Pa · s. If the viscosity is high, problems arise in fluidity, and problems arise in flowability and embedding during pressing. When it is less than 0.05 Pa · s, the heat resistance is insufficient because the molecular weight is too small.

In the above formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. That is, at least half of the glycidyl ether compound has a resorcinol structure. This ratio is important for precipitation of crystals and improvement of heat resistance, and (a) / (b) preferably exceeds 1. Further, when (a) / (b) is 3 or less, the water absorption and toughness can be improved by limiting the amount of the glycidyl ether compound having a resorcinol structure.
In the above formula, n is a repeating unit, and is 0 to 5. When n does not exceed 5, the flowability and fluidity of a prepreg or a resin sheet are controlled. If it exceeds 5, not only the fluidity but also the solubility in a solvent is undesirably raised.
The solubility of the epoxy resin used in the present invention in a solvent is important. In the case of a biphenyl aralkyl type epoxy resin having a similar skeleton, solubility is required in solvents such as methyl ethyl ketone, toluene, and propylene glycol monomethyl ether.
In particular, solubility in methyl ethyl ketone is important, and crystals are not precipitated at 5 ° C., room temperature, or the like for 2 months or more. Although it is related to the ratio of (a) / (b) described above, if the value of (a) is large, crystals are likely to be formed, so it is important that (a) / (b) exceeds 1. .

  The epoxy resin composition of the present invention contains an amine-based curing agent as an essential component. As amine-based curing agents that can be used, diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, naphthalenediamine, aniline and substituted biphenyls (4,4′-bis (chloromethyl) -1,1 ′) -Biphenyl and 4,4'-bis (methoxymethyl) -1,1'-biphenyl) or substituted phenyls (1,4-bis (chloromethyl) benzene, 1,4-bis (methoxymethyl) benzene and Aniline resin obtained by polycondensation with 1,4-bis (hydroxymethyl) benzene or the like, but are not limited thereto.

（式中、ｎは繰り返し数であり、１〜１０である。） Particularly preferred amine-based curing agents are difunctional or higher amine compounds, and a resin having a structure represented by the following formula is preferred.

(In the formula, n is the number of repetitions and is 1 to 10.)

The amine-based curing agents used in the present invention each take the form of crystals or resins.
In the case of crystals, the melting point is preferably 35 to 200 ° C, particularly preferably 40 to 185 ° C. In the case of the melting point, unlike the softening point, the solubility in other resins is also involved, so that the temperature does not necessarily need to be lower than the molding temperature as in the case of resins.
In the case of a resin, the softening point (ring and ball method) of 50 ° C to 150 ° C is preferred, and particularly preferably 50 to 100 ° C. In the case of a resin, a resin having a softening point of 50 ° C. or less is not preferable because a sticky problem occurs, and a resin having a softening point of more than 150 ° C. has a fluidity problem during molding and cannot be molded neatly. There are problems such as not being able to be completely removed.

  The functional group equivalent of the amine resin is 60 to 600 g / eq. (It is preferable that measurement by potentiometric titration is possible. When the active hydrogen equivalent is 60 or less, problems occur in the water absorption and toughness of the cured product. When it exceeds 600, it becomes difficult to maintain heat resistance.

  In the epoxy resin composition of the present invention, the amount of the curing agent used is preferably 0.2 to 0.6 equivalent in terms of the amine equivalent of the amine resin to 1 equivalent of the epoxy group of the epoxy resin. Particularly preferably, it is 0.3 to 0.55 equivalent. If the amount is less than 0.2 equivalents or more than 0.6 equivalents relative to 1 equivalent of the epoxy group, the curing may be incomplete and good cured physical properties may not be obtained, which is not preferable.

  The epoxy resin composition of the present invention may contain a curing accelerator. Specific examples of the curing accelerator that can be used include formic acid, acetic acid, lactic acid, glycolic acid, n-butyric acid, iso-butyric acid, propionic acid, caproic acid, octanoic acid, n-heptyl acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, Thioglycolic acid, phenol, m-cresol, p-chlorophenol, p-nitrophenol, 2,4-dinitrophenol, o-aminophenol, p-aminophenol, 2,4,5-trichlorophenol, resorcinol, hydroquinone, Catechol, phloroglicinol, benzoic acid, p-toluic acid, p-aminobenzoic acid, p-chlorobenzoic acid, 2,4-dichlorobenzoic acid, salicylic acid, phthalic acid, isophthalic acid, terephthalic acid, malic acid, oxalic acid , Succinic, malonic, fumaric, maleic, tartaric, queer Acids such as acids, amines such as monoethanolamine, diethanolamine and triethanolamine, thiophenol, 2-mercaptoethanol, sulfur-containing compounds, 2-methylimidazole, 2-ethylimidazole and 2-ethyl-4-methylimidazole Tertiary amines such as 2- (dimethylaminomethyl) phenol, 1,8-diaza-bicyclo (5,4,0) undecene-7, phosphines such as triphenylphosphine, and octyl. And metal compounds such as tin oxide. The curing accelerator is used in an amount of 0.1 to 5.0 parts by weight based on 100 parts by weight of the epoxy resin as required.

  In the epoxy resin composition of the present invention, another epoxy resin can be used in combination. Specific examples of other epoxy resins that can be used in combination with the epoxy resin of the present invention include bisphenols (bisphenol A, bisphenol F, bisphenol S, biphenol, bisphenol AD, etc.) or phenols (phenol, alkyl-substituted phenol, aromatic-substituted phenol). Phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, alkyl-substituted dihydroxybenzene, dihydroxynaphthalene, etc. and various aldehydes (formaldehyde, acetaldehyde, alkylaldehyde, benzaldehyde, alkyl-substituted benzaldehyde, hydroxybenzaldehyde, naphthaldehyde, glutaraldehyde, phthalaldehyde, croton) Aldehydes, cinnamaldehyde, etc.); phenols and various diene compounds (Dicyclopentadiene, terpenes, vinylcyclohexene, norbornadiene, vinylnorbornene, tetrahydroindene, divinylbenzene, divinylbiphenyl, diisopropenylbiphenyl, butadiene, isoprene, etc.); phenols and ketones (acetone, methyl ethyl ketone) , Methyl isobutyl ketone, acetophenone, benzophenone, etc.); polycondensates of the phenols with aromatic dimethanols (benzene dimethanol, biphenyl dimethanol, etc.); the phenols and aromatic dichloromethyls (Α, α′-dichloroxylene, bischloromethylbiphenyl, etc.); the above-mentioned phenols and aromatic bisalkoxymethyls (bismethoxymethylbenzene, bismethoxymethylbiph) Glycidyl ether-based epoxy resin, alicyclic epoxy resin, glycidylamine-based epoxy resin obtained by glycidylating the above-mentioned polycondensate of bisphenols and various aldehydes or alcohols, etc. Glycidyl ester-based epoxy resins and the like can be mentioned, but the epoxy resin is not limited to these as long as it is a commonly used epoxy resin. These may be used alone or in combination of two or more.

  When blending the epoxy resin composition of the present invention, a conventionally known curing agent can be used in combination. Examples of other curing agents that can be used in combination include acid anhydride compounds, amide compounds, phenol compounds, and carboxylic acid compounds. Specific examples of the curing agent that can be used include dicyandiamide, an amide compound such as a polyamide resin synthesized from a dimer of linolenic acid and ethylenediamine; phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, Acid anhydride compounds such as tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride; bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, terpene diphenol , 4,4'-biphenol, 2,2'-biphenol, 3,3 ', 5,5'-tetramethyl- [1,1'-biphenyl] -4,4'-diol, hydroquinone, resorcinol, naphthalene diol , Tris- (4-hydroxyf Nyl) methane, 1,1,2,2-tetrakis (4-hydroxyphenyl) ethane, phenols (phenol, alkyl-substituted phenol, naphthol, alkyl-substituted naphthol, dihydroxybenzene, dihydroxynaphthalene, etc.) and formaldehyde, acetaldehyde, benzaldehyde , P-hydroxybenzaldehyde, o-hydroxybenzaldehyde, p-hydroxyacetophenone, o-hydroxyacetophenone, a novolak resin which is a polycondensate with furfural, or phenol or cresol with phenylenedimethylol, dimethoxymethyl or methyl halide Or phenol or cresol with bischloromethylbiphenyl, bismethoxymethylbiphenyl or bishydroxymethyl A phenol aralkyl resin which is a reaction product with biphenyl or a reaction product of phenol with benzenediisopropanol, benzenediisopropanol dimethyl ether or benzenebis (chloroisopropane) and modified products thereof, and halogenated bisphenols such as tetrabromobisphenol A Compounds, phenolic compounds such as condensates of terpenes and phenols, imidazole, trifluoroborane-amine complexes, guanidine derivatives, and the like, but are not limited thereto. These may be used alone or in combination of two or more.

The epoxy resin composition of the present invention can also contain a phosphorus-containing compound as a flame-retardant component. The phosphorus-containing compound may be a reaction type or an addition type. Specific examples of the phosphorus-containing compound include trimethyl phosphate, triethyl phosphate, tricresyl phosphate, trixylylenyl phosphate, cresyl diphenyl phosphate, cresyl-2,6-dixylylenyl phosphate, and 1,3-phenylene bis ( Phosphate-based compounds such as dixylylenyl phosphate), 1,4-phenylenebis (dixylylenyl phosphate), and 4,4'-biphenyl (dixylylenyl phosphate); 9,10-dihydro-9- Phosphanes such as oxa-10-phosphaphenanthrene-10-oxide, 10 (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide; activities of epoxy resins and the phosphanes Phosphorus obtained by reacting with hydrogen And a phosphorous ester, a phosphane or a phosphorus-containing epoxy compound is preferable. Particularly preferred are phenyl phosphate), 4,4′-biphenyl (dixylylenyl phosphate) and phosphorus-containing epoxy compounds.
However, from the viewpoints of environmental problems and electrical characteristics, the amount of the phosphate ester compound as described above is preferably phosphate ester compound / epoxy resin ≦ 0.1 (weight ratio). More preferably, it is 0.05 or less. It is particularly preferable not to add a phosphorus compound except for adding as a curing accelerator.

The epoxy resin composition of the present invention may contain an inorganic filler. As the inorganic filler, fused silica, crystalline silica, alumina, calcium carbonate, calcium silicate, barium sulfate, talc, clay, magnesium oxide, aluminum oxide, beryllium oxide, iron oxide, titanium oxide, aluminum nitride, silicon nitride, nitrided Examples include boron, mica, glass, quartz, and mica. It is also preferable to use a metal hydroxide such as magnesium hydroxide or aluminum hydroxide to further impart a flame retardant effect. However, it is not limited to these. Also, two or more kinds may be used in combination. Among these inorganic fillers, silicas such as fused silica and crystalline silica are preferable because of their low cost and good electrical reliability.
In the epoxy resin composition of the present invention, the amount of the inorganic filler used is usually 5% to 70% by weight, preferably 10% to 60% by weight, more preferably 15% to 60% by weight. Range. If the amount is too small, the linear expansion becomes high and warping becomes a problem, and since the thickness of the substrate is being reduced, the rigidity is not sufficient, and the problem appears during the process. If the amount is too large, homogeneity is lost due to sedimentation of the filler or the like, the embedding property of the substrate is deteriorated, and problems such as poor adhesion with metal come out. There is a high possibility that adverse effects will be exerted on the electrical characteristics such as voltage and breakdown voltage.
The shape and particle size of the inorganic filler are not particularly limited, but are usually 0.01 to 50 μm, preferably 0.1 to 15 μm.

  A release agent can be added to the epoxy resin composition of the present invention in order to improve the release from the mold during molding. As the release agent, any of conventionally known release agents can be used. For example, ester waxes such as carnauba wax and montan wax, fatty acids such as stearic acid and palmitic acid and metal salts thereof, and polyolefins such as polyethylene oxide and non-oxidized polyethylene Wax. These may be used alone or in combination of two or more. The compounding amount of these release agents is preferably 0.5 to 3% by weight based on all organic components. If the amount is too small, the release from the mold is poor, and if it is too large, the adhesion to the substrate or the like is poor.

  A coupling agent can be added to the epoxy resin composition of the present invention in order to enhance the adhesion between the inorganic filler and the resin component. As the coupling agent, any of conventionally known coupling agents can be used.For example, vinyl alkoxy silane, epoxy alkoxy silane, styryl alkoxy silane, methacryloxy alkoxy silane, acryloxy alkoxy silane, amino alkoxy silane, mercapto alkoxy silane, isocyanate alkoxy Examples include various alkoxysilane compounds such as silane, alkoxytitanium compounds, and aluminum chelates. These may be used alone or in combination of two or more. The method of adding the coupling agent may be such that after treating the surface of the inorganic filler with the coupling agent in advance, the resin may be kneaded with the resin, or the inorganic filler may be kneaded after the coupling agent is mixed with the resin. .

  A varnish-like composition (hereinafter simply referred to as varnish) can be obtained by adding an organic solvent to the epoxy resin composition of the present invention. Examples of the solvent used include amide solvents such as γ-butyrolactones, N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-dimethylimidazolidinone, and tetramethylene sulfone. Sulfones, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, ether solvents such as propylene glycol monobutyl ether, ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone Solvents, and aromatic solvents such as toluene and xylene. The solvent is used in a range where the solid content of the obtained varnish excluding the solvent is usually 10 to 80% by weight, preferably 20 to 70% by weight.

  Further, known additives can be added to the epoxy resin composition of the present invention, if necessary. Specific examples of additives that can be used include polybutadiene and modified products thereof, modified acrylonitrile copolymer, polyphenylene ether, polystyrene, polyethylene, polyimide, fluororesin, maleimide-based compound, cyanate ester-based compound, silicone gel, and silicone oil. And colorants such as carbon black, phthalocyanine blue and phthalocyanine green.

The resin sheet of the present invention will be described.
The resin sheet using the epoxy resin composition of the present invention has a thickness after drying the varnish on a planar support by various coating methods such as gravure coating, screen printing, metal masking, and spin coating known per se. Is applied to a predetermined thickness, for example, 5 to 100 μm, and then dried. Which coating method is used depends on the type, shape, size, coating film thickness, and support thickness of the support. It is appropriately selected depending on the heat resistance of the body.
Examples of the planar support include various high-grade materials such as polyamide, polyamide imide, polyarylate, polyethylene terephthalate, polybutylene terephthalate, polyether ketone, polyether imide, polyether ether ketone, polyketone, polyethylene, polypropylene, and Teflon (registered trademark). Examples include a film made of a molecule and / or a copolymer thereof, and a metal foil such as a copper foil.
After application, the sheet is dried to obtain a sheet-shaped composition (the resin sheet of the present invention). However, the sheet can be further cured to obtain a sheet-shaped cured product. Further, the solvent may be dried and cured by a single heating.
The epoxy resin composition of the present invention can be applied to both surfaces or one surface of the support by the above-mentioned method and heated to form a layer of the cured product of the present invention on both surfaces or one surface of the support. In addition, it is also possible to create a laminate by bonding and curing the adherend before curing.
Further, the resin sheet of the present invention can be used as an adhesive sheet by peeling it off from the support, and can be brought into contact with the adherend, applied with pressure and heat as necessary, and adhered together with curing.

The prepreg of the present invention will be described.
The prepreg of the present invention is obtained by impregnating a fiber base material with the above resin composition. Thereby, a prepreg excellent in heat resistance, low expansion property and flame retardancy can be obtained. Examples of the fiber base include glass fiber base such as glass woven cloth, glass nonwoven cloth, and glass paper; woven cloth and nonwoven cloth made of synthetic fibers such as paper, aramid, polyester, aromatic polyester, and fluororesin; and metal. Woven fabrics, nonwoven fabrics, mats, and the like made of fibers, carbon fibers, mineral fibers, and the like are included. These substrates may be used alone or as a mixture. Of these, glass fiber substrates are preferred. Thereby, rigidity and dimensional stability of the prepreg can be improved.
The glass fiber substrate preferably contains at least one selected from the group consisting of T glass, S glass, E glass, NE glass, and quartz glass.

Examples of a method of impregnating the fiber composition with the resin composition include a method of immersing the substrate in a resin varnish, a method of applying with a variety of coaters, and a method of spraying with a spray. Among these, the method of immersing the base material in the resin varnish is preferable. Thereby, the impregnation property of the resin composition to the base material can be improved. When the substrate is immersed in the resin varnish, ordinary impregnation coating equipment can be used.
For example, the epoxy resin composition of the present invention as it is, or in the form of a varnish dissolved or dispersed in a solvent, after impregnating a substrate such as a glass cloth, usually in a drying furnace or the like at 80 to 200 ° C. (however, , A solvent is used, and the temperature is set to be higher than the temperature at which the solvent can be volatilized), and dried for 2 to 30 minutes, preferably 2 to 15 minutes to obtain a prepreg.

The metal-clad laminate of the present invention will be described.
The laminate used in the present invention is obtained by subjecting the above prepreg to heat and pressure molding. Thereby, a printed wiring board excellent in heat resistance, low expansion property and flame retardancy can be obtained. In the case of one prepreg, a metal foil is overlaid on both upper and lower surfaces or one surface. Also, two or more prepregs can be laminated. When laminating two or more prepregs, a metal foil or film is laminated on the outermost upper and lower surfaces or one surface of the outermost layer of the laminated prepreg. Next, a printed wiring board can be obtained by subjecting the prepreg and the metal foil to each other to heat-press molding. The heating temperature is not particularly limited, but is preferably from 120 to 220 ° C, particularly preferably from 150 to 200 ° C. The pressure to be applied is not particularly limited, but is preferably 1.5 to 5 MPa, particularly preferably 2 to 4 MPa. If necessary, post-curing may be performed at a temperature of 150 to 300 ° C. in a high-temperature tank or the like.

The printed wiring board of the present invention will be described.
The printed wiring board uses the laminated board as an inner circuit board. Circuits are formed on one or both sides of the laminate. In some cases, through holes may be formed by drilling or laser processing, and electrical connection between both surfaces may be made by plating or the like.

A commercially available or the resin sheet of the present invention or the prepreg of the present invention is overlaid on the interior circuit board and heated and pressed to form a multilayer printed wiring board.
Specifically, the insulating layer side of the resin sheet and the inner layer circuit board are combined, and they are vacuum-heat-pressed using a vacuum-pressing type laminator device or the like, and then the insulating layer is heated and cured by a hot-air drying device or the like. Can be obtained.
The conditions for the heat-press molding are not particularly limited. For example, the molding can be performed at a temperature of 60 to 160 ° C. and a pressure of 0.2 to 3 MPa. The conditions for the heat curing are not particularly limited. For example, the heat curing can be performed at a temperature of 140 to 240 ° C. for a time of 30 to 120 minutes.
Alternatively, the prepreg of the present invention can be obtained by superimposing the prepreg on an inner circuit board and subjecting the prepreg to heat and pressure molding using a flat plate press or the like. Here, the conditions for the heat and pressure molding are not particularly limited, but for example, the molding can be performed at a temperature of 140 to 240 ° C. and a pressure of 1 to 4 MPa. In the heat and pressure molding using such a flat plate press or the like, the insulating layer is cured by heating at the same time as the heat and pressure molding.

  Further, the method for manufacturing a multilayer printed wiring board according to the present invention includes a step of continuously laminating the resin sheet or the prepreg of the present invention on the surface of the inner layer circuit board on which the inner layer circuit pattern is formed; Forming a layer by a semi-additive method.

The curing of the resin sheet or the insulating layer formed from the prepreg of the present invention may be in a semi-cured state in order to facilitate subsequent laser irradiation and removal of resin residues and improve desmear property. In addition, the first insulating layer is partially cured (semi-cured) by heating at a temperature lower than a normal heating temperature, and one or more insulating layers are further formed on the insulating layer to form a semi-cured insulating layer. By heating and curing again to such an extent that there is no practical problem, the adhesion between the insulating layer and between the insulating layer and the circuit can be improved. In this case, the semi-curing temperature is preferably from 80C to 200C, more preferably from 100C to 180C. In the next step, an opening is formed in the insulating layer by irradiating a laser in the next step. Before that, the substrate needs to be peeled off. There is no particular problem whether the peeling of the base material is performed after the formation of the insulating layer, before the heat curing, or after the heat curing.
The inner circuit board used for obtaining the multilayer printed wiring board is preferably formed by forming a predetermined conductor circuit on both surfaces of a copper-clad laminate by etching or the like and subjecting the conductor circuit portion to blackening. Can be used.

  It is preferable to remove resin residues and the like after laser irradiation with an oxidizing agent such as permanganate and dichromate. Further, the surface of the smooth insulating layer can be roughened at the same time, and the adhesion of the conductive wiring circuit formed by the subsequent metal plating can be improved.

Next, an outer layer circuit is formed. The outer layer circuit is formed by connecting the insulating resin layers by metal plating and forming the outer layer circuit pattern by etching. A multilayer printed wiring board can be obtained in the same manner as when a resin sheet or a prepreg is used.
When a resin sheet or a prepreg having a metal foil is used, a circuit may be formed by etching without peeling the metal foil to use it as a conductor circuit. In this case, if an insulating resin sheet with a base material using a thick copper foil is used, it becomes difficult to form a fine pitch in the subsequent formation of a circuit pattern. Therefore, an ultra-thin copper foil of 1 to 5 μm is used, or 12 to 18 μm In some cases, half-etching is performed to reduce the thickness of the copper foil to 1 to 5 μm by etching.

  Further, an insulating layer may be laminated and a circuit may be formed in the same manner as described above. However, due to the design of the multilayer printed wiring board, a solder resist is formed on the outermost layer after the circuit is formed. The method for forming the solder resist is not particularly limited. For example, a method in which a dry film type solder resist is laminated (laminated) and formed by exposure and development, or a method in which a liquid resist is printed is formed by exposure and development. It is done by the method of doing. When the obtained multilayer printed wiring board is used for a semiconductor device, a connection electrode portion is provided for mounting a semiconductor element. The connection electrode portion can be appropriately covered with a metal film such as gold plating, nickel plating, and solder plating. A multilayer printed wiring board can be manufactured by such a method.

Next, the semiconductor device of the present invention will be described.
A semiconductor element having solder bumps is mounted on the multilayer printed wiring board obtained above, and connection with the multilayer printed wiring board is made via the solder bumps. Then, a liquid sealing resin is filled between the multilayer printed wiring board and the semiconductor element to form a semiconductor device. The solder bumps are preferably made of an alloy made of tin, lead, silver, copper, bismuth, or the like.
The method of connecting the semiconductor element and the multilayer printed wiring board is to use a flip chip bonder or the like to align the connection electrode portion on the substrate with the solder bump of the semiconductor element, and then use an IR reflow device, a hot plate, or the like. The solder bumps are heated to a melting point or higher using a heating device, and the multilayer printed wiring board and the solder bumps are connected by fusion bonding. In order to improve connection reliability, a layer of a metal having a relatively low melting point, such as a solder paste, may be formed in advance on the connection electrode portion on the multilayer printed wiring board. Prior to this joining step, the connection reliability can be improved by applying a flux to the solder bumps and / or the surface layer of the connection electrode portion on the multilayer printed wiring board.

  The substrate is used for a motherboard, a network substrate, a package substrate, and the like, and is used as a substrate. Particularly, it is useful as a package substrate as a thin-layer substrate for a single-sided sealing material. When used as a semiconductor encapsulant, the semiconductor device obtained from the composition includes, for example, DIP (dual inline package), QFP (quad flat package), BGA (ball grid array), CSP (chip size package) , SOP (small outline package), TSOP (thin small outline package), TQFP (sync quad flat package), and the like.

Hereinafter, the features of the present invention will be described more specifically with reference to Synthesis Examples and Examples. The materials, processing contents, processing procedures, and the like described below can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples described below.
Here, the measurement conditions of each physical property value are as follows.
-Epoxy equivalent Measured by the method described in JIS K-7236, and the unit is g / eq. It is.
-Softening point Measured by a method according to JIS K-7234, and the unit is ° C.
・ Elastic modulus (DMA)
Dynamic viscoelasticity meter: TA-instRuments, DMA-2980
Measurement temperature range: -30 to 280 ° C
Temperature rate: 2 ° C./min Specimen size: A sample cut into a size of 5 mm × 50 mm was used. Tg: The peak point of Tan-δ in the DMA measurement was defined as Tg. Weight increase rate (%) after boiling test pieces in water at 100 ° C. for 24 hours

Synthesis Example 1
A phenolic resin represented by the following formula ((a) / (b) = 1.3 n) produced according to WO2007 / 007827 while applying a nitrogen purge to a flask equipped with a stirrer, a reflux condenser, and a stirrer. = 1.5 hydroxyl equivalent 134g / eq. (Softening point 93 ° C) 134 parts, epichlorohydrin 450 parts and methanol 54 parts were added, dissolved under stirring, and heated to 70 ° C. Next, 42.5 parts of flaky sodium hydroxide was added in portions over 90 minutes, and the reaction was further carried out at 70 ° C. for 1 hour. After the completion of the reaction, the resultant was washed with water to remove salts, and the resulting organic layer was subjected to distillation under reduced pressure using a rotary evaporator to remove excess solvents such as epichlorohydrin. To the residue was added and dissolved 500 parts of methyl isobutyl ketone, 17 parts of a 30% by weight aqueous sodium hydroxide solution was added under stirring, and the mixture was reacted for 1 hour, and then washed with water until the washing water of the oil layer became neutral. From the obtained solution, methyl isobutyl ketone and the like were distilled off under reduced pressure using a rotary evaporator to obtain 195 parts of the epoxy resin (EP1) of the present invention. The epoxy equivalent of the obtained epoxy resin is 211 g / eq. The melt viscosity at a softening point of 71 ° C. and 150 ° C. (ICI melt viscosity cone # 1) was 0.34 Pa · s.

Example 1
A-1 (amine equivalent: 198 g / eq, active hydrogen equivalent: 97.5 g / eq, softening point: 55 ° C.) was used as a curing agent for the epoxy resin (EP1) obtained in Synthesis Example 1 with respect to 1 molar equivalent of epoxy equivalent. 0.5 parts by weight, salicylic acid as a catalyst was mixed at a ratio (parts by weight) of 1 part by weight with respect to 100 parts by weight of the epoxy resin, and the mixture was uniformly mixed and kneaded using a mixing roll to obtain an epoxy resin composition. I got This epoxy resin composition was pulverized with a mixer and further tableted with a tablet machine. The tableted epoxy resin composition was subjected to transfer molding (175 ° C. × 60 seconds), and after demolding, cured at 160 ° C. × 2 hours + 180 ° C. × 6 hours to obtain a test piece for evaluation. Table 1 shows the evaluation results.
The details of the epoxy resin used for the evaluation are shown in Table 2 below.

Comparative Examples 1 to 7
In Example 1, the epoxy resin (EP1) obtained in Synthesis Example 1 and various epoxy resins were equi-equivalent to A-1 or HA-1 (a phenol novolak resin manufactured by Meiwa Kasei Kogyo Co., Ltd.) as a curing agent. A test piece for evaluation was obtained using triphenylphosphine (TPP) or salicylic acid as a catalyst in the same formulation and method as in Example 1. Table 1 shows the evaluation results.

  From Table 1, when comparing Example 1 with Comparative Example 3, a cured product having specifically excellent heat resistance and water absorption properties can be obtained by using an amine-based curing agent as compared with using a phenol resin as a curing agent. Was confirmed.

(Fig. 1)

In addition, FIG. 1 shows a graph in which the cured physical properties obtained in Table 1 are plotted on the horizontal axis with heat resistance (Tg) and on the vertical axis with water absorption characteristics (%).
From FIG. 1, it can be confirmed that the cured products of Comparative Examples 1 to 3 and Comparative Examples 4 to 7 have a correlation that the higher the Tg, the higher the water absorption. On the other hand, the cured product using the epoxy resin of the present invention and the amine-based curing agent has high heat resistance, but has a low water absorption, and a specific combination different from the aforementioned correlation. It can be confirmed that there is.

Claims (9)

Epoxy resins represented by the following general formula (1), a bifunctional or polyfunctional amine curing agent, and epoxy resin composition for a curing accelerator as essential components,
The amine equivalent of the bifunctional or higher amine-based curing agent is 0.2 to 0.6 equivalent per 1 equivalent of the epoxy group of the epoxy resin, and the content of the curing accelerator is 0.1 to 100 parts by weight of the epoxy resin. 5.0 parts by weight,
The bifunctional or higher amine curing agent is an aniline resin obtained by polycondensation of aniline and a substituted biphenyl or a substituted phenyl,
An epoxy resin composition wherein the curing accelerator is at least one selected from acids, sulfur-containing compounds, imidazoles, and metal compounds.

(In the formula, the ratio of (a) and (b) is (a) / (b) = 1 to 3. G represents a glycidyl group. N is the number of repetitions and is 0 to 5.)   A prepreg obtained by impregnating a fiber base material with the epoxy resin composition according to claim 1.   The prepreg according to claim 2, wherein the fiber material is a glass fiber base material.   4. The prepreg according to claim 2, wherein the glass fiber base includes at least one selected from the group consisting of T glass, S glass, E glass, NE glass, and quartz glass. 5.   A metal-clad laminate wherein a metal foil is laminated on at least one surface of the prepreg according to any one of claims 2 to 4.   A resin sheet formed by forming an insulating layer comprising the epoxy resin composition according to claim 1 on a film or a metal foil.   A printed wiring board using the metal-clad laminate according to claim 5 for a circuit board.   A printed wiring board obtained by curing the prepreg according to any one of claims 2 to 4 and / or the resin sheet according to claim 6. A semiconductor device comprising a semiconductor element mounted on the printed wiring board according to claim 7.