JP2001019832A - Epoxy resin composition for semiconductor sealing and semiconductor device sealed therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition which can give a sealing material having low stress properties and toughness by mixing an epoxy resin with a phenolic resin in which a crosslinked diallyl phthalate resin powder is dispersed, a cure accelerator, and an inorganic filler. SOLUTION: This composition comprises an epoxy resin (A), a phenolic resin (B) in which a crosslinked diallyl phthalate resin powder is dispersed, components A and B being used in amounts to give an equivalent ratio of the epoxy groups of component A to the hydroxy groups of component B of 1/(0.5-2.0), 0.01-1.0 wt.% cure accelerator such as triphenylphosphine, and 70-90 wt.% inorganic filler, such as a fused silica powder, having a mean particle diameter of 10-50 μm. Component A is exemplified by a phenol novolak, bisphenol A, or biphenyl epoxy resin having an epoxy equivalent of 150-250 and a softening point of 50-130 deg.C. Component B is exemplified by a phenol novolac resin or phenolaralkyl resin containing 0.3-2.0 wt.% crosslinked diallyl phthalate resin powder and having a hydroxy equivalent of 100-170 and a softening point of 70-90 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition for semiconductor encapsulation as an encapsulating material having excellent low stress and toughness, and a highly reliable semiconductor device obtained by using the same. .

[0002]

2. Description of the Related Art Semiconductor devices such as transistors and ICs are
From the viewpoint of enabling protection from an external environment and handling of elements, the semiconductor device is sealed with a plastic package or the like to form a semiconductor device. An epoxy resin composition has been widely used as the plastic package forming material. Various properties are required for the epoxy resin composition as the sealing material, and one of them is an excellent low stress property. Numerous proposals have been made to provide this excellent low stress property.

[0003]

In recent years, there has been a demand for an epoxy resin composition serving as the above-mentioned encapsulating material having high toughness as well as excellent low stress properties. However, the conventional epoxy resin composition has a disadvantage that the shrinkage stress at the time of molding is high, and as a result, damage to the semiconductor element to be sealed is large, and the toughness at the time of solder mounting is poor. have. As described above, an epoxy resin composition having high toughness in addition to excellent low stress properties has not yet been obtained.

The present invention has been made in view of such circumstances, and an epoxy resin composition for semiconductor encapsulation which can be used as an encapsulating material having both low stress and toughness, and a semiconductor device obtained using the same. The purpose is to provide.

[0005]

In order to achieve the above-mentioned object, the present invention provides, as a first gist, an epoxy resin composition for semiconductor encapsulation containing the following components (A) to (D). (A) Epoxy resin. (B) A phenol resin in which a crosslinked diallyl phthalate resin powder is uniformly dispersed. (C) a curing accelerator. (D) an inorganic filler.

Further, a semiconductor device in which a semiconductor element is encapsulated by using the above-mentioned epoxy resin composition for encapsulating a semiconductor is a second semiconductor device.
The summary of the

[0007] The inventor of the present invention has conducted researches mainly on the components thereof in order to obtain a sealing material having both excellent low stress and excellent toughness. In the course of that research, we focused on crosslinked diallyl phthalate resin powder (hereinafter referred to as "crosslinked diallyl phthalate resin powder") as a compounding component capable of imparting both low stress and toughness. . As a result, simply blending the cross-linked diallyl phthalate resin powder together with other components causes the cross-linked diallyl phthalate resin powder to aggregate and become uniformly dispersed in the composition, making it difficult to exert the above-described effects. Ascertained. As a result of further study, the crosslinked diallyl phthalate resin powder and the phenol resin were mixed in advance, and the remaining components were blended. The present inventors have found that a sealing material excellent in both strength and toughness can be obtained, and have reached the present invention. That is, the present invention, in which the above-mentioned crosslinked diallyl phthalate resin powder is premixed and uniformly dispersed to target not a epoxy resin but a phenol resin, is a reaction between an allyl group of the crosslinked diallyl phthalate resin powder and a phenolic hydroxyl group of the phenol resin. It is considered that the toughness of the obtained cured product is improved because the crosslinking property of the phenol resin is increased.

In particular, when the spherical aggregate of the crosslinked diallyl phthalate resin powder composed of a spherical aggregate of microgel having an average particle size of 0.05 to 0.5 μm has an average particle size of 1 to 50 μm, the sealing material The crosslinked diallyl phthalate resin powder is efficiently dispersed in the phenol resin therein, and a sealing material having low stress and excellent toughness can be obtained. That is, if the average particle diameter is larger than the above range, so-called "lumps" are easily formed in the phenol resin, and it is difficult to obtain a sufficient dispersion, so that the molding quality and the stress tend to be reduced. On the other hand, if the average particle size is smaller than the above range, it is difficult to be efficiently dispersed in the phenol resin, and the powder tends to be scattered and the workability tends to be reduced.

When the content of the crosslinked diallyl phthalate resin powder is 0.3 to 2.0% by weight in the whole epoxy resin composition for semiconductor encapsulation, the toughness of the epoxy resin composition is improved, and Excellent low stress property is obtained. That is, if the content of the cross-linked diallyl phthalate resin powder is less than the above range, it is difficult to obtain the effect of improving the toughness and low stress, and if it is more than the above range, the fluidity of the epoxy resin composition is reduced. This is because the molding quality tends to decrease.

The average particle size of the inorganic filler is as follows:
When it is in the range of 10 to 50 μm, the molding quality is excellent. That is, when the average particle size of the inorganic filler is smaller than the above range, the fluidity is reduced, and there is a tendency that the molding quality is deteriorated. Because it becomes easy.

[0011]

Next, embodiments of the present invention will be described in detail.

The epoxy resin composition for semiconductor encapsulation of the present invention comprises an epoxy resin (A component) and a phenol resin (B component) in which a crosslinked diallyl phthalate resin powder is uniformly dispersed.
, A curing accelerator (C component), and an inorganic filler (D component)
And is usually in the form of a powder or a tablet obtained by compressing the powder.

The epoxy resin (A component) is not particularly limited, and various epoxy resins can be used. For example, cresol novolak type epoxy resin, phenol novolak type epoxy resin, novolak bis A
Type epoxy resin, bisphenol A type epoxy resin, biphenyl type epoxy resin and the like. As such an epoxy resin, those having an epoxy equivalent of 150 to 250 and a softening point of 50 to 130 ° C are preferable.

The phenol resin (component B) used together with the epoxy resin (component A) has a crosslinked diallyl phthalate resin powder uniformly dispersed in the phenol resin. The phenol resin serves as a curing agent for the epoxy resin (component A), and is not particularly limited, and various conventionally known phenol resins, for example, phenol novolak resin, cresol novolak resin, and phenol aralkyl resin And the like. It is preferable to use a phenol resin having a hydroxyl equivalent of 100 to 170 and a softening point of 70 to 90 ° C.

The mixing ratio of the epoxy resin (component A) and the phenol resin (component B) is such that the hydroxyl equivalent in the phenol resin is 0.5 to 2.0 equivalent per 1 equivalent of the epoxy group in the epoxy resin. It is preferable to mix them. It is more preferably 0.8 to 1.2 equivalents.

The cross-linked diallyl phthalate resin powder uniformly dispersed in the phenol resin is completely cross-linked, and does not melt even when heated, for example, during melting and mixing with other components, and retains the powder shape. Things that can be done. The crosslinked diallyl phthalate resin powder is composed of, for example, a powder of a crosslinked copolymer of di (meth) allyl phthalate and a vinyl compound other than di (meth) allyl phthalate.

The above-mentioned diallyl (meth) allyl phthalate means both diallyl phthalate and dimethallyl phthalate, and the above-mentioned diallyl (meth) allyl phthalate includes diallyl orthophthalate, diallyl metaphthalate, diallyl terephthalate and orthophthalate. Dimethallyl acid, dimethallyl metaphthalate, dimethallyl terephthalate and the like. These may be used alone or in combination of two or more. Of these, diallyl orthophthalate, diallyl metaphthalate, and diallyl terephthalate are preferred.

The vinyl compounds other than the above di (meth) allyl phthalate include vinyl compounds having a functional group reactive with an epoxy group and vinyl compounds having no functional group reactive with an epoxy group. Separated.

Among the vinyl compounds having a functional group reactive with the epoxy group, the vinyl compounds having an acid group include acrylic acid, methacrylic acid, itaconic acid,
Unsaturated carboxylic acids such as maleic acid, mono (meth) allyl phthalate, mono (meth) allyl maleate, mono (meth) allyl fumarate or acid anhydrides or salts thereof, styrenesulfonic acid,
Unsaturated sulfonic acids such as acrylamide-2-methylpropanesulfonic acid or salts thereof, vinylphosphonic acid,
Examples thereof include vinyl compounds having a carboxyl group, a sulfonic acid group or a phosphoric acid group, such as unsaturated phosphoric acid such as acid phosphoxylethyl (meth) acrylate, and acid anhydrides or salts of these vinyl compounds.

Among the vinyl compounds having a functional group reactive with the epoxy group, the vinyl compounds having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and (meth) acrylate. 3-hydroxypropyl acrylate, 2-hydroxybutyl (meth) acrylate, 4- (meth) acrylate
Vinyl compounds having a hydroxyl group such as hydroxybutyl, (meth) allyl alcohol, (meth) allyl lactate, (meth) acrylic acid monoester of glycerin, (meth) acrylic acid monoester of pentaerythritol, allyl alcohol and methacrylic alcohol. Can be Particularly, 2-hydroxyethyl (meth) acrylate is preferred.

Among the vinyl compounds having a functional group reactive with the epoxy group, the vinyl compounds having an epoxy group include divinylbenzene monoepoxide,
Vinyl compounds, such as diisopropenylbenzene monoepoxide, in which at least one vinyl group of a plurality of aromatic conjugated vinyl compounds is left in the molecule and others are epoxidized, butadiene, isoprene monoepoxide, 1,5-hexadiene monoepoxide , Vinyl cyclohexene monoepoxides and other aliphatic vinyl compounds having a plurality of unsaturated bonds, one of which is epoxidized while leaving another vinyl group, (meth) allyl glycidyl ether, 2-methylglycidyl (meth) allyl Ether, ethylene glycol di (meth) allyl ether monoepoxide, propylene glycol di (meth) allyl ether monoepoxide, hexanediol (meth) allyl ether monoepoxide, trimethylolpropane di (meth) allyl ether monoepoxide De, pentaerythritol tri (meth) allyl ether monoepoxide, dimethylolcyclohexane di (meth) allyl ether monoepoxide,
Tri (meth) allyl isocyanurate monoepoxide,
Vinyl compounds having a plurality of the same or different allyl ether groups or methallyl ether groups in the molecule, such as tri (meth) allyl isocyanurate diepoxide, and at least one of which is epoxidized while leaving at least one vinyl group of the vinyl compound Di (meth) allyl carbonate monoepoxide, di (meth) allyl monoepoxide oxalate, di (meth) allyl monoepoxide succinate, di (meth) allyl monoepoxide fumarate, di (meth) allyl monoepoxide maleate, adipine Vinyl having a plurality of same or different allyl ester groups or methallyl ester groups in the molecule such as di (meth) allyl monoepoxide acid, di (meth) allyl monoepoxide cyclohexanedicarboxylate, and di (meth) allyl monoepoxide phthalate At least one of the compounds Other vinyl compounds which are epoxidized, glycidyl (meth) acrylate, an epoxy group, such as Metagurishijiru (meth) acrylate (meth) acrylic acid esters and the like and.

In the vinyl compound having a functional group reactive with the epoxy group, the vinyl compound having an amino group includes aminoethyl (meth) acrylate,
N, N-dimethylaminoethyl (meth) acrylate,
N, N-diethylaminoethyl (meth) acrylate,
(Meth) acrylates having an amino group such as N, N-dimethylaminopropyl (meth) acrylate;
Compounds having amino groups such as (meth) allylamine, di (meth) allylamine, methyldi (meth) allylamine, tri (meth) allylamine, dimethyldi (meth) allylammonium chloride and having the same or different (meth) allyl groups Kind.

Further, (meth) acrylamide, N-
(Meth) acrylamides which may have an N-alkyl substituent such as methyl (meth) acrylamide, N-methylol (meth) acrylamide, N- (o-methylmethylol) (meth) acryl Acid amide, N- (o-butylmethylol) (meth) acrylamide, N, N-
N-methylol substitution such as di (o-methylmethylol) (meth) acrylamide, N, N-di (o-butylmethylol) (meth) acrylamide or N- (o-
Alkylmethylol) Substituted vinyl compounds having a carbonyl group such as (meth) acrylamide, methyl vinyl ketone, ethyl vinyl ketone, etc .; vinyl compounds having an aldehyde group such as (meth) acrolein and crotonaldehyde; acetoacetoxyethyl Vinyl compounds having a group in which two carbonyl groups are condensed with the same methylene group or methine group such as (meth) acrylate, and having an alioxysilyl group such as vinyltrimethoxysilane and (meth) acryloxypropyltrimethoxysilane Vinyl compounds and the like.

Next, the vinyl compounds having no functional group reactive with the epoxy group include (meth) acrylates, styrenes, α-methylstyrenes,
(Meth) allyl ethers, (meth) allyl esters, vinyl compounds having a cyano group, aliphatic hydrocarbons having an unsaturated bond, vinyl ethers, vinyl esters, maleic esters, fumaric esters, vinyl silanes, Examples thereof include (meth) allyl alcohol, tri (meth) allyl cyanurate, and tri (meth) allyl isocyanurate.

Examples of the (meth) acrylate include (meth) acrylates having 1 to 8 carbon atoms in the alcohol. Examples of the acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, and n-acrylate.
-Butyl, isobutyl acrylate, t-butyl acrylate, pentyl acrylate, cyclopentyl acrylate,
Acrylic esters comprising a saturated aliphatic alcohol having 1 to 8 carbon atoms, such as hexyl acrylate, cyclohexyl acrylate, heptyl acrylate, methylcyclohexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, and the like, may be mentioned.

Examples of the methacrylate include methyl methacrylate, ethyl methacrylate, and n-methacrylic acid.
-Propyl, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-methacrylate
A saturated aliphatic alcohol having 1 to 8 carbon atoms, such as butyl, pentyl methacrylate, cyclopentyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, heptyl methacrylate, methylcyclohexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate; And methacrylic esters consisting of

Further, (meth) acrylates comprising an alcohol of an aliphatic hydrocarbon such as 2-ethylhexyl (meth) acrylate, and (meth) acrylates containing an aromatic group such as benzyl (meth) acrylate , 2-chloroethyl (meth) acrylate, trifluoroethyl (meth) acrylate, perfluoroalkyl (meth) acrylate, halogenated alcohol components such as (meth) acrylate of perfluoroalcohol substituted only at 1-position with hydrogen Or methacrylic acid esters consisting of ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth)
Acrylate, butanediol di (meth) acrylate, hexanediol di (meth) acrylate, glycerin tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate , Triazine tri (meth) acrylate, phosphazene tri (meth) acrylate and the like having plural same or different acrylic or methacrylic groups in the molecule, allyl (meth) acrylate, methallyl (meth) acrylate And (meth) acrylic esters having an allyl group.

The styrenes include styrene, ortho- or para-chlorostyrene, ortho- or para-methylstyrene, ortho- or para-methylstyrene, ortho- or para-chloromethylstyrene, divinylbenzene, trivinylbenzene and the like. And styrenes substituted with an alkyl group or a halogenated alkyl group or a vinyl group.

The α-methylstyrenes include α-methylstyrenes.
Methylstyrene or parachloro α-methylstyrene,
Α-Methylstyrenes in which the aromatic ring such as ortho- or para-chloromethyl α-methylstyrene and diisopropenylbenzene are substituted with a halogen or an alkyl group, a halogenated alkyl group or a vinyl group.

The (meth) allyl ethers include
Methyl (meth) allyl ether, ethyl (meth) allyl ether, propyl (meth) allyl ether, butyl (meth) allyl ether, hexyl (meth) allyl ether, cyclohexyl (meth) allyl ether, 2-ethylhexyl (meth) allyl ether Allyl ethers or methallyl ethers such as phenyl (meth) allyl ether, cresyl (meth) allyl ether, di (meth) allyl ether, allyl (meth) allyl ether, ethylene glycol di (meth) allyl ether,
Propylene glycol di (meth) allyl ether, hexanediol di (meth) allyl ether, trimethylolpropanedi (meth) allyl ether, pentaerythritol tri (meth) allyl ether, dimethylolcyclohexanedi (meth) allyl ether, di (meth) yl Iv) Vinyl compounds having a plurality of allyl ether groups or methallyl ether groups in the molecule of the same kind or different types such as allyl ether.

As the above (meth) allyl esters,
Allyl esters or methallyl esters such as (meth) allyl acetate, (meth) allyl propionate, (meth) allyl butyrate, (meth) allyl benzoate, (meth) allyl lactate, di (meth) allyl carbonate, dioxalate (Meth) allyl, di (meth) allyl succinate, di (meth) allyl fumarate, di (meth) allyl maleate, di (meth) allyl adipate, di (meth) allyl cyclohexanedicarboxylate Vinyl compounds having a plurality of allyl ester groups or methallyl ester groups in the same or different form are mentioned.

Examples of the vinyl compounds having a cyano group include (meth) acrylonitrile. Furthermore, the aliphatic hydrocarbons having an unsaturated bond include aliphatic hydrocarbons having one unsaturated bond in a molecule such as propylene, butene, pentene, hexene, and cyclohexene; butadiene, isoprene, Examples include vinyl compounds such as aliphatic hydrocarbons having a plurality of unsaturated bonds, such as 5-hexadiene and vinylcyclohexene.

Examples of the vinyl ether include methyl vinyl ether, ethyl vinyl ether, isopropyl vinyl ether, N-amyl vinyl ether, isoamino vinyl ether, (meth) allyl vinyl ether and divinyl ether. Examples of the vinyl ester include vinyl esters such as vinyl acetate, vinyl propionate, and long-chain vinyl carboxylate.

Examples of the maleic ester include maleic esters of saturated or unsaturated aliphatic hydrocarbon alcohols such as dimethylmaleic acid, diethylmaleic acid, dibutylmaleic acid and di (meth) allylmaleic acid. Examples of the fumaric acid esters include fumaric acid esters of saturated aliphatic hydrocarbon alcohols such as dimethyl fumaric acid, diethyl fumaric acid, and dibutyl fumaric acid.

The above-mentioned vinylsilanes are substituted with saturated or unsaturated aliphatic hydrocarbons such as trimethylvinylsilane, dimethyldivinylsilane, diethyldivinylsilane, trimethyl (meth) allylsilane, dimethyldi (meth) allylsilane and tetra (meth) allylsilane. Silanes.

The vinyl compound is preferably a (meth) acrylic acid ester having 1 to 8 carbon atoms in the alcohol. Among the above acrylates, methyl acrylate, methyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, pentyl acrylate, cyclopentyl acrylate, acrylic Hexyl acrylate, cyclohexyl acrylate, heptyl acrylate,
Esters composed of a saturated aliphatic alcohol having 1 to 3 carbon atoms, such as methylcyclohexyl acrylate, octyl acrylate, and 2-ethylhexyl acrylate, are preferred.
Among the above methacrylates, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, pentyl methacrylate, pentyl methacrylate, cyclopentyl methacrylate, Hexyl methacrylate, cyclohexyl methacrylate, heptyl methacrylate, methylcyclohexyl methacrylate, octyl methacrylate, and 2-ethylhexyl methacrylate are preferred.

More preferably, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, (meth) acrylic Isobutyl acid, tert-butyl (meth) acrylate, (meth)
2-ethylhexyl acrylate is exemplified.

The crosslinked diallyl phthalate resin powder used in the present invention can be produced by a conventionally known method, for example, emulsion polymerization, using the above monomer components in an appropriate mixing ratio. It can also be produced by dispersion polymerization or suspension polymerization.

The cross-linked diallyl phthalate resin powder is a microgel spherical aggregate having an average particle diameter of 0.05 to 0.5 μm, and the spherical aggregate has an average particle diameter of 1 to 5 μm.
0 μm, particularly preferably 2 μm.
The range is from 0 to 30 μm. That is, if the average particle size is too large outside the above range, so-called "lumps" are easily formed in the phenol resin, and it is difficult to obtain a sufficient dispersion. . Further, if the average particle size is too small than the above range, the dispersion in the phenol resin due to scattering of the powder, etc. is not sufficiently performed,
This is because the workability tends to decrease. The average particle size of the crosslinked diallyl phthalate resin powder is, for example, a laser type particle sizer (manufactured by Horiba, Ltd., LA-91).
0).

The amount of the crosslinked diallyl phthalate resin powder to be used is preferably set in the range of 0.3 to 2.0% by weight in the whole epoxy resin composition for semiconductor encapsulation finally obtained. . Particularly preferably 0.5 to
1.5% by weight. That is, if the crosslinked diallyl phthalate resin powder is too small, such as less than 0.3% by weight,
If the effect of improving the toughness and low stress is difficult to obtain, and if it exceeds 2.0% by weight, the flowability of the epoxy resin composition is reduced, and the molding quality tends to be reduced. It is.

The curing accelerator (component (C)) used together with the phenol resin (component (B)) in which the epoxy resin (component (A)) and the crosslinked diallyl phthalate resin powder are uniformly dispersed is not particularly limited, and is conventionally known. Is used. For example, amine type, imidazole type,
Examples include phosphorus-based, boron-based, phosphorus-boron-based curing accelerators, and specific examples thereof include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, and 1,8.
-Diazabicyclo (5,4,0) undecene-7 and the like. These may be used alone or in combination of two or more.

The content of the curing accelerator (component C) is 0.01 to 1.0 in the whole epoxy resin composition for semiconductor encapsulation.
It is preferable to set the weight% in the range. Particularly preferably, it is in the range of 0.05 to 0.5% by weight. That is, if the content of the curing accelerator (component C) is too small, such as less than 0.01% by weight, it is difficult to obtain a desired curing promoting effect. If too long, the fluidity of the epoxy resin composition tends to decrease.

The inorganic filler (component D) used together with the above components A to C is not particularly limited, but includes not only crystalline and fused silica powder but also alumina oxide, beryllium oxide, silicon carbide, silicon nitride and the like. Is raised. In particular, it is preferable to use a fused silica powder, and it is particularly preferable to use one having an average particle size of 10 to 50 μm, and particularly preferably 20 to 40 μm.
That is, when the average particle size of the inorganic filler is smaller than the above range, the fluidity is reduced, and there is a tendency that the molding quality is deteriorated. Because it becomes easy. The average particle size of the inorganic filler can be measured by, for example, a laser type particle size analyzer (LA-910, manufactured by Horiba, Ltd.) as in the case of the crosslinked diallyl phthalate resin powder.

The content of the inorganic filler (component D) is as follows:
It is preferably set in the range of 70 to 90% by weight in the whole epoxy resin composition for semiconductor encapsulation, particularly preferably 7% by weight.
5 to 85% by weight. That is, when the content of the inorganic filler (component D) is less than 70% by weight, the toughness of the epoxy resin composition decreases, and cracks and molding quality of a molded package are reduced due to an increase in stress during shrinkage. This is because when the content exceeds 90% by weight, the fluidity of the epoxy resin composition tends to decrease.

Further, the epoxy resin composition for semiconductor encapsulation of the present invention may further comprise, if necessary, a flame retardant, a flame retardant auxiliary, a mold release agent, γ-glycidoxy, in addition to the above-mentioned components A to D. Other additives such as a silane coupling agent such as propyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminoethylaminopropyltrimethoxysilane can be appropriately used.

Examples of the flame retardant include novolak type brominated epoxy resin and the like.
Antimony trioxide, antimony pentoxide, or the like is used.
These may be used alone or in combination of two or more.

Examples of the release agent include compounds such as higher fatty acids, higher fatty acid esters, and higher fatty acid calcium. For example, polyethylene wax is used, and these may be used alone or in combination of two or more.

Further, in addition to the above-mentioned various additives, silicone oil, silicone rubber, synthetic rubber or the like may be added to the epoxy resin composition for semiconductor encapsulation of the present invention in order to further reduce the stress. An ion trapping agent such as a hydrotalcite compound or bismuth hydroxide may be blended for the purpose of improving the reliability in the performance test.

The epoxy resin composition for semiconductor encapsulation of the present invention is obtained, for example, as follows. First, a phenol resin is heated and melted in advance, and a crosslinked diallyl phthalate resin powder is blended and mixed with the phenol resin to uniformly disperse the crosslinked diallyl phthalate resin powder in the phenol resin. Then, using the phenol resin (component B) blended with the crosslinked diallyl phthalate resin powder, the other remaining components, an epoxy resin (component A), a curing accelerator (component C),
The inorganic filler (D component) and other additives are blended and melt-mixed. Next, it is obtained by cooling it to room temperature, pulverizing it by a known means, and compressing it if necessary.

The encapsulation of a semiconductor element using such an epoxy resin composition is not particularly limited, and can be performed by a known molding method such as ordinary transfer molding.

Since the semiconductor device thus obtained uses a phenol resin (component B) in which the crosslinked diallyl phthalate resin powder is uniformly dispersed, the above crosslinked The diallyl phthalate resin powder is uniformly dispersed without aggregation. Therefore, a sealing resin layer having high toughness as well as excellent low stress properties is formed.

Next, examples will be described together with comparative examples.

First, the following components were prepared.

[Epoxy resin A] o-cresol novolak type epoxy resin (epoxy equivalent 195, softening point 70
℃)

[Epoxy resin B] Novolac type brominated epoxy resin (epoxy equivalent: 455, softening point: 80 ° C.)

[Phenol resin] Phenol novolak resin (hydroxyl equivalent 105, softening point 83 ° C)

[Crosslinked diallyl phthalate resin powder] DAP-WB Powder manufactured by Daiso Co. (Aggregates of microgels having a particle size of about 0.1 μm and having an average particle diameter of 30 μm)
m)

[Silane coupling agent] γ-glycidoxypropyltrimethoxysilane

[Fused silica powder] Average particle size 30 μm, shape = crushed

[Flame retardant aid] Antimony trioxide

[Curing accelerator] Triphenylphosphine

On the other hand, a modified epoxy resin and a modified phenol resin were prepared in advance using the above components.

[Preparation of Modified Epoxy Resin] 100 parts by weight of the above epoxy resin A (hereinafter abbreviated as “parts”) was charged into a universal mixer and heated to 150 ° C. After the epoxy resin A is completely melted, 20 parts of the crosslinked diallyl phthalate resin powder is added thereto, and the mixture is heated and mixed (165 ° C.) for 150 minutes to uniformly disperse the crosslinked diallyl phthalate resin powder. I got

[Preparation of Modified Phenol Resin a] 100 parts of the above phenol resin was charged into a universal mixing kettle and heated to 150 ° C. After the phenol resin is completely melted, the crosslinked diallyl phthalate resin powder 20 is added thereto.
The mixture was heated and mixed (165 ° C.) for 150 minutes to obtain a modified phenolic resin a in which the crosslinked diallyl phthalate resin powder was uniformly dispersed.

[Preparation of Modified Phenolic Resin b] The compounding amount of the crosslinked diallyl phthalate resin powder was changed to 4 parts. Otherwise, a modified phenolic resin b was obtained in the same manner as the modified phenolic resin a.

[Preparation of Modified Phenolic Resin c] The blending amount of the crosslinked diallyl phthalate resin powder was changed to 25 parts. Otherwise, a modified phenolic resin c was obtained in the same manner as the modified phenolic resin a.

[0067]

Examples 1 to 6 and Comparative Examples 1 to 3 The components shown in the following Tables 1 and 2 were blended in the proportions shown in the same table, and were melt-kneaded for 10 minutes in a mixing roll machine (100 ° C.).
Next, the melt was cooled and pulverized to obtain a powdery epoxy resin composition for encapsulating a semiconductor.

[0068]

[Table 1]

[0069]

[Table 2]

Using the thus obtained epoxy resin compositions of Examples and Comparative Examples, according to the following method,
The spiral flow value, flow tester viscosity, flexural strength and flexural modulus, Charpy impact strength, and thermal shock test were measured and evaluated. The results are shown in Tables 3 and 4 below.

[Spiral flow value] EMMI 1-6 at 175 ± 5 ° C using a spiral flow measurement mold.
6 was measured.

[Flow Tester Viscosity] Each of the above epoxy resin compositions was precisely weighed in an amount of 2 g and formed into a tablet. Then, put this in the pot of the Koka type flow tester,
The measurement was performed with a load of 0 kg. The melt viscosity of the sample was determined from the moving speed of the piston when the molten epoxy resin composition was extruded through a die hole (diameter 1.0 mm × 10 mm).

[Bending Strength and Flexural Modulus] The above epoxy resin composition was transferred by a transfer molding machine.
A sample (cured body) was produced by performing pressure molding at 175 ° C. for 2 minutes under a pressing condition of 100 kg / cm ² and then performing post-curing at 175 ° C. for 5 hours. The shape of the sample was 10 mm long × 4 mm wide × 80 mm long. Using this, it measured according to JISK7171.

[Charpy impact strength] The above epoxy resin composition was transferred to a transfer mold machine at 175
A sample (cured body) was produced by performing pressure molding at 100 ° C. for 2 minutes under a pressing condition of 100 kg / cm ² and then performing post-curing at 175 ° C. for 5 hours. The shape of the sample was 15 mm long × 15 mm wide × 120 mm long. Using this, it measured according to JISK7111.

[Heat Shock Test] Using the above epoxy resin composition, a die pad size: 8.0 × 8.0 mm, a copper frame QFP-80 package (four-way flat package size: 14 mm × 20 mm × thickness 2.0 m)
m) was molded. Using this package, a thermal shock test was performed under the following conditions to evaluate the cracking property of the package. (Test conditions) 150 ° C x 5 minutes (in silicone oil)
One cycle was performed at −50 ° C. × 5 minutes (in silicone oil), and 100 cycles were repeated. And, the case where no package crack occurred was indicated by ○, and the case where package crack occurred was indicated by ×.

[0076]

[Table 3]

[0077]

[Table 4]

From the above Tables 3 and 4, all of the products of Examples have high bending strength and impact strength, and no cracks of the package occurred in the thermal shock test.

On the other hand, the product of the comparative example was inferior to at least one of the bending characteristics, the Charpy impact strength and the thermal shock test. In particular, in the thermal shock test, package cracks occurred in all the comparative examples.

[0080]

As described above, the present invention is an epoxy resin composition for semiconductor encapsulation containing a phenol resin (component (B)) in which a crosslinked diallyl phthalate resin powder is uniformly dispersed. For this reason, the crosslinked diallyl phthalate resin powder is uniformly dispersed in the composition, and as a result, a sealing material excellent in both low stress property and toughness is obtained. Therefore,
In a semiconductor device sealed with a resin using the epoxy resin composition, a semiconductor device having high reliability can be obtained.

In particular, when the average particle diameter of the spherical aggregate of the crosslinked diallyl phthalate resin powder comprising the spherical aggregate of microgels having an average particle diameter of 0.05 to 0.5 μm is in the range of 1 to 50 μm, The crosslinked diallyl phthalate resin powder is efficiently dispersed in the phenol resin therein, and a sealing material having low stress and excellent toughness is obtained.

When the content of the crosslinked diallyl phthalate resin powder is 0.3 to 2.0% by weight in the whole epoxy resin composition for semiconductor encapsulation, the toughness of the epoxy resin composition is improved, and Excellent low stress property is obtained. That is, if the content of the cross-linked diallyl phthalate resin powder is less than the above range, it is difficult to obtain the effect of improving the toughness and low stress, and if it is more than the above range, the fluidity of the epoxy resin composition is reduced. This is because the molding quality tends to decrease.

When the average particle size of the inorganic filler (component D) is in the range of 10 to 50 μm, a sealing material having excellent molding quality can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 23/29 H01L 23/30 R 23/31 F-term (Reference) 4J002 BF053 CC032 CC042 CC052 CC272 CD041 CD051 CD061 DE097 DE147 DJ007 DJ017 EU136 EW016 EY016 FD017 FD130 FD142 FD156 FD170 GQ05 4J036 AD07 AD08 AF06 AF08 AF15 AF27 DC02 DC40 DC46 DD07 DD09 FA02 FA05 FB01 FB06 FB07 HA11 JA07 KA05 4M109 AA01 BA01 CA21 EA02 EB03 EB02 EB03 EB03 EB03 EB03 EB03 EB03 EB03 EB03 EB04

Claims (5)

[Claims] 1. An epoxy resin composition for encapsulating a semiconductor, comprising the following components (A) to (D): (A) Epoxy resin. (B) A phenol resin in which a crosslinked diallyl phthalate resin powder is uniformly dispersed. (C) a curing accelerator. (D) an inorganic filler. 2. The crosslinked diallyl phthalate resin powder is a micro-gel spherical aggregate having an average particle size of 0.05 to 0.5 μm, and the spherical aggregate has an average particle size of 1 to 50 μm.
The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein m is in the range of m. 3. The content of the crosslinked diallyl phthalate resin powder is set in the range of 0.3 to 2.0% by weight in the whole epoxy resin composition for semiconductor encapsulation.
Or the epoxy resin composition for semiconductor encapsulation according to 2. 4. The epoxy resin composition for semiconductor encapsulation according to claim 1, wherein the inorganic filler as the component (D) has an average particle size of 10 to 50 μm. 5. A semiconductor device in which a semiconductor element is encapsulated using the epoxy resin composition for encapsulating a semiconductor according to claim 1.