JPS62275149A - Resin composition for use in sealing semiconductor - Google Patents

Abstract

PURPOSE:To provide the title comspn. which has a low modulus, a low coefficient of thermal expansion, excellent resistance to heat and impact, etc. and does not stain molds, consisting of a specified modified epoxy resin, a curing agent and an inorg. filler. CONSTITUTION:A 4-20C alkyl acrylate (e.g. butyl acrylate) is polymerized in the presence of a graft polymer obtd. by polymerizing a vinyl monomer (e.g., styrene) in the presence of a polyepoxy resin (e.g., a novolak epoxy resin) to obtain a modified epoxy resin (A) contg. 5-20wt% non-rigid vinyl polymer having a particle size of not larger than 0.5mu uniformly dispersed therein. 100pts. wt. component A is blended with a stoichiometric amount (based on that of the epoxy group of the component A) of a curing agent (B) (e.g., a phenolic novlak), 200-800pts.wt. inorg. filler (C) (e.g., crystalline silica) and optionally. an epoxy resin (D).

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] The present invention is directed to a thin metal material having a low modulus of elasticity, a low coefficient of thermal expansion, and excellent thermal shock resistance without impairing heat resistance. The present invention relates to a resin composition for semiconductor encapsulation that is used for encapsulating electronic components such as semiconductors that require solidity.

[Conventional technology]

In recent years, so-called plastic encapsulation using thermosetting resins such as epoxy resins has been widely put into practical use as a method for encapsulating semiconductors, taking advantage of economic advantages such as low raw material costs and suitability for mass production. In particular, resin compositions containing polyfunctional epoxy resins, novolac type phenolic resins, and inorganic fillers as main components have become mainstream as sealing resins because they have excellent heat resistance, moldability, and electrical properties.

[Problem that the invention seeks to solve]

On the other hand, as semiconductor chips have become more highly integrated, their chip sizes have become larger. In addition, the shape of the puff cage is becoming smaller and thinner, as seen in flat packages, as opposed to larger chips, as chips are more densely packaged on substrates. For this reason, defective phenomena that were not observed with conventional sealing resins have been introduced. In other words, stress in the resin due to the difference in coefficient of thermal expansion between the sealing resin and the chip increases the size of the chip and thins the resin layer, resulting in thermal shock that causes fracture phenomena such as cranking of the Buffy Soylon film or cranking of the sealing resin. This causes a decrease in the moisture resistance of semiconductors, which in turn causes a decrease in reliability.

Therefore, it is desired to develop a sealing resin that has less stress.

One possible way to reduce stress is to reduce the coefficient of thermal expansion of the resin to reduce the difference between it and that of the chip, but the difference between the coefficient of thermal expansion of the resin and that of the chip is large, so in order to reduce this requires the use of a large amount of inorganic filler with a low coefficient of thermal expansion in the resin, but currently a considerable amount of inorganic filler is already being used, and it is necessary to increase this amount even more! Doing so may cause deterioration of moldability. On the other hand, attempts have been made to add plasticizers or use flexible epoxy resins or phenolic resins in order to lower the elastic modulus of the resin and reduce stress; The cured product had a problem in terms of heat resistance.

In addition, as typified by JP-A-58-108220, methods have been invented in which rubber particles are dispersed in a sealing resin to provide crank resistance while maintaining heat resistance. There were several problems, such as mold contamination and poor impact resistance at high temperatures exceeding the glass transition temperature of the sealing resin, such as in a solder bath. If the mold is heavily contaminated, the mold must be cleaned frequently, which is extremely inconvenient because productivity decreases. In addition, if the thermal shock resistance at high temperatures is poor, the reliability after solder dipping will be reduced, which is a fatal defect in encapsulating materials for ICs and the like.

The present invention is designed for use in semiconductors that require low stress and excellent thermal shock resistance, etc., and that does not cause mold contamination during molding. The purpose of the present invention is to provide a resin composition for soil use.

[Means for solving problems]

As a result of various studies, the present inventors discovered that it is effective to uniformly disperse fine particles of a soft vinyl polymer containing acrylic acid esters as a main component in a resin composition.
As a result of further studies on the vinyl polymer composition, particle size, etc., the present invention was achieved. That is, the present invention has the following features: a) A soft vinyl polymer mainly composed of an alkyl acrylate having an alkyl group having 4 or more carbon atoms is uniformly dispersed in a graft polymer of an epoxy resin and a vinyl polymer with a particle size of 0.5 μ or less. This is a resin composition for semiconductors and earth, characterized in that the main components thereof are a modified epoxy resin, b) a curing agent, C) an inorganic filler, and optionally d) an epoxy resin.

As the epoxy resin used in a) of the present invention, commonly used epoxy resins can be used as long as they are polyhydric epoxy resins, and glycidylated products such as phenol novolac and talesol novolac can be used because of their heat resistance and electrical properties. Novolafuku eboxy resin is preferred, but other molecule contains 2
Compounds with more than 10 active hydrogen atoms, such as bisphenol A, anti-hydroxydiphenylmethane, resorcinol,
Bishydroxydiphenyl ether, polyhydric phenols such as tetrabromobisphenol A, ethylene glycol, neopentyl glycol, glycerin, trimethylolpropane, pentaerythritol, diethylene glycol, polypropylene glycol, bisphenol A
- Reacting epichlorohydrin or 2-methylepichlorohydrin with polyhydric alcohols such as ethylene oxide adducts, trishydroxyethyl isocyanurate, polyamino compounds such as ethylenediamine and aniline, and polyhydric carboxy compounds such as adipic acid, phthalic acid, and isophthalic acid. One or more epoxy resins selected from aliphatic (including alicyclic) epoxy resins such as glycidyl-type epoxy resins, dicyclopentadiene diepoxide, butadiene dimer diepoxide, etc. obtained by I can do it.

The graft polymer of an epoxy resin and a vinyl polymer in a) of the present invention is typically produced by polymerizing a vinyl monomer to form the vinyl polymer in the presence of an epoxy resin. Here, the term graft polymer includes what is usually called a block polymer.
Vinyl monomers used to make the vinyl polymer include alkenyl aromatics such as styrene and vinyltoluene, methyl methacrylate, dodecyl methacrylate, butoxyethyl methacrylate, glycidyl methacrylate, mimethyl acrylate, butyl acrylate, - Acrylic esters such as ethylhexyl acrylate, hydroxyethyl acrylate, trimethylolpropane triacrylate, etc.; acrylic compounds without ester groups such as acrylonitrile, acrylic acid, butoxymethylacrylamide, methacrylamide, etc.; vinyl acetate, vinyl laurel; Representative examples include non-conjugated vinyl compounds such as ester, vinyl persatate, vinyl chloride, vinyldene chloride, ethylene and allyl acetate, and conjugated diene compounds such as butadiene, isoprene and chloroprene.Other examples include dibutyl fumarate and monomethyl maleate. Polymerizable vinyl compounds such as , diethyl itaconate, etc. can also be used. In order to polymerize the vinyl monomers described above to obtain a vinyl polymer, a radical initiator such as lauroyl peroxide, benzoyl peroxide, tert-butyl perbenzoate, dimethyl dibenzoyl perpivalate, diter Chaributyl peroxide, 1.1-bistercharybutyl peroxide 3.3.5-trimethylcyclohexane, dimethyl ditertiarybutyl peroxyhexane, tertiary butyl cumyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, kinimen hydroper Peroxides such as oxide, tert-butyl peroxyallyl carbonate, dioctyl peroxydicarbonate, tert-butyl peroxymaleic acid, succinic acid peroxide, tert-butyl peroxyisopropyl carbonate, hydrogen peroxide, azobisiso Typically, radical polymerization is carried out using an azo compound such as butyronitrile or azobisdimethylvaleronitrile.

Further, if necessary, a reducing agent may be used in combination to carry out so-called redox polymerization, and a polymerization inhibitor such as hydroquinone or a chain transfer agent such as dodecyl mercaptan may be used.

In addition, in order to promote grafting, it is effective to introduce a polymerizable double bond or a chemical bond that can be grafted into the epoxy resin. , methylol acrylamide,
Butoxymethylacrylamide, hydroxyethyl methacrylate, glycidyl methacrylate, maleic anhydride, monoethyl itaconate, monobutyl fumarate, chloromethylstyrene, phosphoxyethyl mequaacrylate, chlorohydroxypropyl methacrylate, parahydroxystyrene, dimethylaminoethyl A typical method is to react a compound having a functional group and a polymerizable double bond, such as methacrylate, with an epoxy resin in advance.

In the present invention, the epoxy resin or the vinyl polymer may remain free in the graft polymer without being grafted.

The modified epoxy resin a) can be obtained by polymerizing a monomer that forms a flexible vinyl polymer in the presence of the above-mentioned graft polymer of an epoxy resin and a vinyl polymer by a conventional method. The flexible vinyl polymer used in the present invention must be a polymer mainly composed of acrylate having an alkyl group having 4 or more carbon atoms, preferably 20 or less carbon atoms. For polymers mainly composed of alkyl acrylates having less than 4 carbon atoms, the resulting soft vinyl polymer has a particle size of 0.
．． If the thickness exceeds 5 μm, low stress, which is the objective of the present invention, cannot be achieved and thermal shock resistance cannot be improved. Examples of soft vinyl polymers mainly composed of alkyl acrylates having an alkyl group having 4 or more carbon atoms include butyl acrylate, 2-ethylhexyl acrylate, octyl acrylate, decyl acrylate, lauryl acrylate, tridecyl acrylate, myristyl acrylate, and cetyl. It is a polymer mainly composed of one or more types such as acrylates, and it is also possible to copolymerize monomers that can be copolymerized with these acrylates, but the proportion used is such that the resulting copolymer is soft, i.e. It is liquid or rubbery and has a particle size of 0.5 μm or less, and although it depends on the type of monomer, it is usually 80% by weight or less of the total monomers. These monomers are not particularly limited, but include, for example, acrylates such as methyl acrylate, ethyl acrylate, and propyl acrylate, alkyl methacrylates having an alkyl group having 1 to 24 carbon atoms, cyclohexyl acrylate, benzyl acrylate, and phenoxyethyl. acrylate, phenoxydiethylene glycol acrylate, tetrahydrofurfuryl alcohol acrylate,
Isobornyl acrylate, dicyclopentagenyl acrylate, hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroquine propyl acrylate, glycidyl methacrylate, 1,6-hexane glycol diacrylate, neopentyl glycol diacrylate, polypropylene glycol diacrylate, tri Various acrylic acids such as methylolpropane triacrylate, methacrylic esters, acrylonitrile, acrylic compounds without ester groups such as acrylic acid, butoxymethylacrylamide, methacrylamide, vinyl acetate, vinyl laurate, vinyl persatate, Such as vinyl chloride, nyldene chloride, ethylene, allyl acetate, etc.

Representative examples include non-conjugated vinyl compounds, conjugated diene compounds such as butadiene, isoprene, and chloroprene;
Polymerizable vinyl compounds such as dibutyl fumarate, monoethyl maleate, diethyl itaconate, etc. can be used.

As mentioned above, modified epoxy resin is produced by polymerizing a 7-mer, which forms a soft vinyl polymer, in the presence of a graft polymer of an epoxy resin and a vinyl polymer using a conventional method. The particle size varies depending on the type of vinyl polymer and the type of soft vinyl polymer, but it is obtained as a composition dispersed in .
If it exceeds 5μ, the purpose of the present invention cannot be achieved, but in order to achieve the purpose of the present invention of reducing stress and improving impact resistance, it is less than 0.5μ, preferably 0.2μ. The particle size must be 0.01μ or more. Regarding particle size control of soft vinyl polymers, the type of vinyl polymer that forms the graft polymer with the epoxy resin,
It can be controlled by the amount of double bonds introduced into the epoxy resin, depending on the selection of the seven-mer composition forming the soft vinyl polymer.

The composition of the present invention may optionally contain an epoxy resin as d). As the epoxy resin in d), all the epoxy resins used in a) above can be used, and both may be the same or different. There is no problem.

In addition, the soft vinyl polymer is required to be 5% by weight or more based on the total of the epoxy resins used in a) and d), and 10 to 20% by weight is particularly preferable. If it is less than 5% by weight, low stress can be achieved. Not done. Moreover, if it exceeds 241%, the strength decreases significantly and it is difficult to put it into practical use.

To adjust the above soft vinyl polymer to the desired amount a.
When used in producing the modified epoxy resin of (d), the amount of nyl monomer may be adjusted, but it is easier to do so by changing the amount of the epoxy resin of (d), and from this point of view, d) It is preferable to use an epoxy resin in combination.

As the curing agent b) used in the present invention, a novolac type phenolic resin obtained by reacting phenols such as phenol and alkylphenol with formaldehyde or paraformaldehyde is generally used, but in addition, modified novolac type phenolic resin, Aralkyl phenolic resins, commonly used amine curing agents, acid anhydrides, etc. can be used alone or in combination.

Although there is no particular restriction on the amount to be added, a stoichiometric amount of the epoxy group of the epoxy resin and the functional group of the curing agent is preferred.

Examples of the inorganic filler C) used in the present invention include powders such as crystalline silica, fused silica, alumina, talc, calcium silicate, calcium carbonate, mica, clay, and titanium white, or glass fibers and carbon fibers. These may be used singly or as a mixture, but from the viewpoint of thermal expansion coefficient, thermal conductivity, etc., crystalline, meltable, etc. silica powder is usually used.

The blending amount is 2 parts per 100 parts by weight of the above epoxy resin.
00 to 800 parts by weight is preferred; if it is less than 200 parts by weight, the coefficient of thermal expansion will be large and good impact resistance will not be obtained; if it exceeds 800 parts by weight, the fluidity of the resin will decrease and moldability will be poor, making it difficult to put it into practical use. hard.

The resin composition for semiconductor encapsulation of the present invention includes a) a soft vinyl polymer mainly composed of an alkyl acrylate having an alkyl group having 4 or more carbon atoms in a graft polymer of an epoxy resin and a vinyl polymer; The main components are a modified epoxy resin uniformly dispersed in particle size, b) a curing agent, C) an inorganic filler, and optionally d) an epoxy resin, but in practical use imidazoles, tertiary amines, Hardening accelerators such as phenols, organometallic compounds, and organic phosphines, mold release agents such as fatty acid amides, fatty acid salts, and waxes, flame retardants such as bromine compounds, antimony, and phosphorus, colorants such as carbon black, and silane cups. It is also possible to appropriately blend a ring agent and the like.

The resin composition for semiconductor encapsulation of the present invention can be easily obtained as a molding material by sufficiently premixing with a mixer or the like, kneading with a hot roll or a melt mixer such as a Nigu, and then cooling and pulverizing. I can do it.

The thus obtained resin composition for semiconductor encapsulation of the present invention has a low elastic modulus, a small coefficient of thermal expansion, and exhibits excellent thermal shock resistance. Alternatively, when used to encapsulate small and thin semiconductors such as flat packages, excellent reliability can be obtained. In addition, there is no mold contamination during molding, making it suitable for long-term continuous production.

〔Example〕

The present invention will be specifically explained with reference to examples, but the present invention is not limited to the examples. In the following, parts mean parts by weight unless otherwise specified.

Example 1 100 parts of orthocresol novolak epoxy resin (epoxy equivalent: 217), 10 parts of toluene, and 1 part of methacrylic acid were reacted at 120 to 125°C for 2 hours in the presence of a tertiary amine, and then 3.6 parts of butyl acrylate was added. , glycidyl methacrylate 0.1 part, t-butylperoxy 2-
0.05 part of ethylhexanoate is reacted at 100°C for 1 hour. Further, 30 parts of butyl acrylate, 0.6 parts of neopentyl glycol diacrylate, and 0.15 parts of 1,1-bis(L-butylperoxy)3,3.5-tricyclohexane were continuously added dropwise for 4 hours, and then further. After reacting for 4 hours, the solvent was removed under residual pressure to obtain a modified epoxy resin (A) (epoxy equivalent: 285).

Orthocresol novolak epoxy resin (epoxy equivalent: 217) 56 parts, modified epoxy resin (^) 44 parts, novolac type phenol resin (phenol equivalent: 106) 4
1 part, 0.85 parts of triphenylphosphine, 400 parts of fused silica previously treated with a silane coupling agent,
2 parts of carbon black and 2.5 parts of carnauba wax were mixed in a mixer, and the mixture was melted for 3 minutes with a hot roll at 80 to 90°C, cooled and pulverized to obtain a molding resin composition.

Using this composition, transfer molding (175°C, 30°C)
Kg/cd for 3 minutes) to obtain test pieces for physical property tests and a 16-pin DIP (equipped with 4 parts and 8 m/m elements) for thermal shock tests. These specimens were molded at 175°C.
After curing for a period of time, various tests were conducted.

Example 2 Orthocresol novolak epoxy resin (epoxy equivalent: 21?) 100 parts, toluene 1o part, methacrylic a
20.6 parts at 120-125°C in the presence of a tertiary amine.
After reacting for an hour, 2-ethylhexyl acrylate 3
．． 6 parts, 0.1 part of glycidyl methacrylate, and 0.05 part of t-butylperoxy 2-ethylhexanoate in 1 part.
React at 00°C for 1 hour. Furthermore, 30 parts of 2-ethylhexyl acrylate, 0.4 part of glycidyl methacrylate, 0.4 part of neopentyl glycol acrylate, 1.
1-bis(t-butylperoxy)3.4 hours while continuously adding 0.15 parts of 3.5-tricyclohexane dropwise.
After further reaction for 4 hours, the solvent was removed under reduced pressure to obtain a modified epoxy resin (B) (epoxy equivalent: 297).

Various tests were conducted in the same manner as in Example 1 using the above modified epoxy resin.

Example 3 After reacting 100 parts of orthocresol novolac epoxy resin (epoxy equivalent: 217), 1 part of toluene, and 1 part of methacrylic acid at 120 to 125°C for 2 hours in the presence of a tertiary amine, 2-ethylhexyl acrylate 3 .6 parts, glycidyl methacrylate 0.1 part, and -butylperoxy 2-ethylhexanoate 0.05 parts at 100°C.
Let it react for 1 hour. Additionally, 30 parts of 2-ethylhexyl acrylate, 0.4 parts of glycidyl methacrylate, 0.4 parts of neopentyl glycol acrylate, and 0.15 parts of 1.1-bis(t-butylperoxy)3,3.5-tricyclohexane. The mixture was reacted for 4 hours while continuously dropping , and then reacted for another 4 hours, and the solvent was removed under reduced pressure to obtain a modified epoxy resin (C) (Konkushita 1296).

Using the above modified epoxy resin, various tests were conducted in the same manner as in Example 1.

Example 4 100 parts of orthocresol novolac epoxy resin (epoxy equivalent: 217), 10 parts of toluene, and 0.9 parts of methacrylic acid were reacted for 2 hours at 120 to 125°C in the presence of a tertiary amine, and then 3.6 parts of lauryl acrylate was reacted. , glycidyl methacrylate 0.1 part, t-butyl peroxy 2
- 100 parts of ethylhexanoate.

React at C for 1 hour. Furthermore, lauryl acrylate 30
parts, glyfudyl methacrylate 0.4 parts, neopentyl glycol diacrylate 0.6 parts, 1.1-bis(L
-butylperoxy) 3,3.5-tricyclohexane was continuously added dropwise for 4 hours, and then reacted for another 4 hours. The solvent was removed under reduced pressure to give a modified epoxy resin (D) (epoxy equivalent: 305 ) was obtained.

Various tests were conducted in the same manner as in Example 1 using the above modified epoxy resin.

Example 5 The molding resin composition of Example 3 was produced in the same manner as in Example 3 except that the amount of orthocresol novolac epoxy resin was changed to 13 parts and the amount of modified epoxy resin (B) was changed to 87 parts. I went.

Example 6 100 parts of orthocresol novolak epoxy resin (epoxy equivalent weight 217), 10 parts of toluene, and 0.4 part of methacrylic acid were mixed at 120-125°C in the presence of a tertiary amine.
After reacting for an hour, 2-ethylhexyl acrylate 1
．． 3 parts and 0.02 parts of t-butylperoxy 2-ethylhexanoate were reacted at 100°C for 1 hour.

Furthermore, 11 parts of 2-ethylhexyl acrylate, 0.2 parts of neopentyl glycol diacrylate, and 0.06 parts of 1.1-bis(t-butylperoxy)3,3.5-tricyclohexane were continuously added dropwise. After reacting for 4 hours and then for an additional 4 hours, the solvent was removed under reduced pressure to obtain a modified epoxy resin (G) (epoxy equivalent: 245).

100 parts of the above modified epoxy resin, 43 parts of novolak type phenol resin (phenol equivalent: 106), 0.85 parts of triphenylphosphine, 400 parts of fused silica previously treated with a silane coupling agent, 2 parts of carbon blank,
A molding resin composition was obtained using 2.5 parts of carnauba wax in the same manner as in Example 1, and further test pieces were prepared and various tests were conducted.

Comparative Example 1 100 parts of ortho-cresol novolak epoxy resin (epoxy [217]), novolac type phenol resin (
49 parts of phenol equivalent (106), 0.85 part of triphenylphosphine, 412 parts of fused silica previously treated with a silane cuff pulling agent, 2 parts of carbon black, and 2.5 parts of carnauba wax were mixed in a mixer, and further 80~
After melt-mixing for 3 minutes with a heated roll at 90°C, a molding resin composition was obtained by cooling and pulverizing.

Using this composition, transfer molding (175°C, 30°C)
Kg/cII! , 3 minutes) for physical property tests and a 16-pin DIP (4 x 8 m/3 minutes) for thermal shock tests.
m elements mounted) was obtained. After molding, these specimens were 17
After post-curing at 5° C. for 4 hours, each test was conducted.

Comparative Example 2 After reacting 100 parts of orthocresol novolac epoxy resin (epoxy equivalent: 21?), 10 parts of toluene, and 0.9 parts of meccrylic acid at 120 to 125°C for 2 hours in the presence of a secondary amine, 3.0 parts of ethyl acrylate was reacted. 6 parts, glycidyl methacrylate 0.1 part, t-butyl peroxy 2 parts
- 0.05 part of ethylhexanoate is reacted at 100°C for 1 hour. Additionally, 30 parts of ethyl acrylate, 0.4 parts of glycidyl methacrylate, 0.6 parts of neopentyl glycol diacrylate, and 0.15 parts of 1,1-bis(7-butylperoxy)3,3.5-)lycyclohexane.
The mixture was reacted for 4 hours while continuously dropping a portion of the mixture, and then for another 4 hours, and the solvent was removed under reduced pressure to obtain a modified epoxy resin (E) (1298 epoxy resin).

Various tests were conducted in the same manner as in Example 1 using the above modified epoxy resin.

Comparative Example 3 Orthocresol novolac epoxy resin (epoxy equivalent: 21?) 100 parts, toluene 10 parts, methacrylic a
After reacting the O and S parts in the presence of a tertiary amine at 120 to 125°C for 2 hours, 3.6 parts of butyl acrylate, 0.1 part of glycidyl methacrylate, and 2 parts of L-butyl peroxy
- 0.05 part of ethylhexanoate is reacted at 100°C for 1 hour. Furthermore, 30 parts of butyl acrylate, 0.4 parts of glycidyl methacrylate, 0.6 parts of neopentyl glycol diacrylate, and 0.15 parts of 1.1-bis(t-butylperoxy)3.3.5-tricyclohexane were continuously added dropwise. After reacting for 4 hours, and then for another 4 hours, the solvent was removed under reduced pressure to obtain a modified epoxy resin (F) (epoxy equivalent: 306).

Various tests were conducted in the same manner as in Example 1 using the above modified epoxy resin.

Comparative Example 4 90 parts of orthocresol novolak epoxy resin (epoxy equivalent: 217), 10 parts of bisphenol diglycidyl ether (epoxy equivalent: 190), 49 parts of novolak type phenol resin (phenol equivalent: 106), 0.85 part of triphenylphosphine, A resin composition for molding was obtained in the same manner as in Example 1 using 412 parts of fused silica treated with a force/knobling agent, 2 parts of carbon black, and 2.5 parts of carnauba wax, and further test pieces were prepared and various tests were conducted. .

Comparative Example 5 90 parts of orthocresol novolak epoxy resin (epoxy equivalent: 217), 10 parts of styrene-butadiene rubber, novolac type phenol resin (phenol equivalent: 106)
44 parts of triphenylphosphine, 0.85 parts of triphenylphosphine, 400 parts of fused silica previously treated with a coupling agent, 2 parts of carbon blank, and 2.5 parts of carnauba wax to obtain a molding resin composition in the same manner as in Example 1. Furthermore, test pieces were prepared and various tests were conducted.

The contents of the above examples and comparative examples are shown in Table 1, and the test results are shown in Table 2.

〔Effect of the invention〕

As explained in Examples and Comparative Examples 5, the resin composition for semiconductors according to the present invention has a low elastic modulus, a small coefficient of thermal expansion, and exhibits excellent impact resistance. When used for the encapsulation of highly integrated semiconductors or small and thin semiconductors such as flat packages, excellent reliability can be obtained, and there is no mold contamination (because it is suitable for long-term continuous production). It can be said that this invention is industrially useful.

Claims (2)

[Claims] (1)a) A soft vinyl polymer mainly composed of an alkyl acrylate having an alkyl group having 4 or more carbon atoms in a graft polymer of an epoxy resin and a vinyl polymer is 0.5μ
A resin composition for semiconductor encapsulation, characterized in that the main components thereof are a modified epoxy resin uniformly dispersed with the following particle diameters, b) a curing agent, and c) an inorganic filler. (2)a) A soft vinyl polymer mainly composed of an alkyl acrylate having an alkyl group having 4 or more carbon atoms is uniformly dispersed in a graft polymer of an epoxy resin and a vinyl polymer with a particle size of 0.5μ or less. A resin composition for semiconductor encapsulation, characterized in that the main components thereof are a modified epoxy resin, b) a curing agent, c) an inorganic filler, and d) an epoxy resin.