JPH08311310A - Epoxy resin composition for sealing and semiconductor device using the same - Google Patents

Abstract

PURPOSE: To obtain an epoxy resin composition for sealing capable of protecting water penetration and excellent in moisture resistance by blending powdery silica obtained by treating with a specific surface treating agent and forming a thick coupling layer on the surface of the powdery silica. CONSTITUTION: This epoxy resin composition for sealing is constituted of powdery silica the surface of which is treated with (A) an epoxy resin (preferably a novolak-based epoxy resin, etc.), (B) a curing agent (preferable a phenolic resin such as a phenolic novolak resin, etc.) and (C) a produced material expressed by formula I [n is 1-3, R is CH3 or CH2 CH3 ; X is an organic functional group having vinyl, methacryl on the terminal] and obtained by heating plural silane coupling agents having different terminals of the organic functional groups. The component C, e.g. can be obtained by using 0.21 pt.wt. silicon compound of formula II having an epoxy on the terminal of the organic functional group as the silane coupling agent and 0.19 pt.wt. silicon compound of formula III having an amino on the terminal of the organic functional group, reacting the both silicon compounds by heating and dipping 84 pts.wt. powdery silica in the reaction product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encapsulating epoxy resin composition used for encapsulating semiconductor elements and the like, and a semiconductor device using the composition.

[0002]

2. Description of the Related Art A semiconductor element is physically and chemically protected,
As an encapsulating material for fixing, an epoxy resin composition containing an epoxy resin, a curing agent, and silica powder as constituent materials is known, and a semiconductor device encapsulated with these epoxy resin compositions is widely used. . 2. Description of the Related Art In recent years, there has been a demand for improved moisture resistance in accordance with various usage methods and demand for improved productivity. For example, during mounting, if the epoxy resin composition is rapidly exposed to high temperatures, such as being directly immersed in solder after being stored in a high humidity condition for a long time, cracks may occur in the cured product of the epoxy resin composition. It's an easy situation.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above facts, and an object thereof is to provide a sealing epoxy resin composition having excellent moisture resistance, and this sealing epoxy. It is to provide a semiconductor device using a resin composition.

[0004]

The epoxy resin composition for encapsulation according to claim 1 of the present invention is an epoxy resin, a curing agent,
And a sealing epoxy resin composition comprising a surface-treated silica powder as a constituent material, wherein the silica powder has a plurality of organic functional groups having different terminal groups represented by the following general formula [1]. It is characterized in that the silane coupling agent is surface-treated with a product obtained by reacting with heat.

[0005]

Embedded image

[Wherein n = 1, 2, 3 is shown, and R is -C
H _3, shows a -CH ₂ CH _3, X end group is a vinyl group,
An organic functional group having any one of a methacrylic group, an epoxy group, an amino group and a mercapto group is shown. A semiconductor device according to claim 2 of the present invention is characterized by being encapsulated with the epoxy resin composition for encapsulation according to claim 1.

Hereinafter, the present invention will be described in detail. The epoxy resin composition for sealing of the present invention is an epoxy resin, a curing agent,
Also, the surface-treated silica powder is used as a constituent material.

Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, novolac type epoxy resin, biphenyl type epoxy resin and alicyclic epoxy resin. These may be used alone or in combination of two or more. Of these, novolac-based epoxy resins and biphenyl-type epoxy resins are suitable because the cured product has a good glass transition temperature (Tg).

Examples of the curing agent include phenol novolac resin, acid anhydrides, amines and the like.
These may be used alone or in combination of two or more. Of these, phenol resins such as phenol novolac resins are suitable. The mixing ratio of the curing agent is not particularly limited and may be appropriately selected.

The surface-treated silica powder characteristically used in the present invention is represented by the above general formula [1],
It is a product obtained by surface-treating a plurality of silane coupling agents having different organic functional group end groups with a product obtained by heating and reacting with each other.

The plurality of silane coupling agents differ in the terminal groups of the organic functional groups. When two kinds of silane coupling agents are used, one silane coupling agent has an epoxy group as the terminal group of the organic functional group, and the other silane coupling agent has an epoxy group at the terminal group of the organic functional group. It has a vinyl group, a methacryl group, an amino group, or a mercapto group other than the group. When a silane coupling agent having a different end group of this organic functional group is heated and reacted,
Polymerize to make high molecular weight products. When the silica powder is surface-treated with the above product, a thick coupling layer is formed on the surface of the silica powder, so that infiltration of water can be suppressed. As a result, the moisture resistance of the epoxy resin composition containing the silica powder as a constituent material is improved.

The compounding ratio of the silane coupling agents having different end groups of the organic functional groups is preferably such that the end groups of the organic functional groups are equimolar. The conditions for the heating reaction of the above silane coupling agent are a temperature of 100 ° C to 1
Suitable is 50 ° C. and time of 0.5 to 2 hours. Temperature is 10
When the temperature is lower than 0 ° C and lower than 0.5 hours, a sufficient product cannot be obtained, and when the temperature is higher than 150 ° C for 2 hours, the reaction with the silane coupling agent proceeds too much and the product is silica. May not fully react with powder. Specific examples of the silane coupling agent include silicon compounds represented by the following structural formulas [2] and [3] as those having an epoxy group at the terminal group of the organic functional group. Examples of those having an amino group as a group include silicon compounds represented by the following structural formulas [4] and [5].

[0013]

Embedded image

[0014]

[Chemical 4]

[0015]

Embedded image

[0016]

[Chemical 6]

The encapsulating epoxy resin composition of the present invention contains, as necessary, a curing accelerator, a bleeding inhibitor, and a flame retardant together with the above-mentioned epoxy resin, curing agent and surface-treated silica powder. , A release agent, a colorant and the like are appropriately contained. Examples of the curing accelerator include tertiary amines, imidazoles,
Organic phosphorus compounds and the like can be mentioned, and the above-mentioned exudation preventive agent prevents exudation of resin at the time of molding, and silicone oil and the like can be mentioned. Examples of the flame retardant include antimony trioxide, hydrated alumina and the like, examples of the release agent include natural carnauba, stearic acid, stearate and the like, and examples of the colorant include carbon black and
Examples include pigments such as metal oxides.

After the above-mentioned components are uniformly mixed by using a mixer, a blender or the like, they are kneaded by using a kneader, a roll or the like to obtain an epoxy resin composition. After kneading, it is cooled and solidified if necessary, and pulverized into powder or granules for use.

A semiconductor device is obtained by encapsulating a semiconductor element or the like by compression molding, transfer molding, injection molding or the like using the encapsulating epoxy resin composition. Since the semiconductor device is encapsulated with the encapsulating epoxy resin composition, it is less susceptible to water intrusion. Therefore, the moisture resistance is excellent.

[0020]

The epoxy resin composition for encapsulation according to claim 1 of the present invention is obtained by heating and reacting a plurality of silane coupling agents represented by the general formula [1] with different organic functional end groups. The silica powder surface-treated with the obtained product having a large molecular weight is used as a constituent material. For this reason, since the silica powder forms a thick coupling layer, infiltration of water can be suppressed.

Since the semiconductor device according to the second aspect of the present invention is encapsulated with the encapsulating epoxy resin composition according to the first aspect, moisture infiltration is small.

[0022]

【Example】

Example 1 The silica powder was surface-treated as follows. As the silane coupling agent, a silicon compound represented by the structural formula [2] having an epoxy group at the terminal group of the organic functional group 0.2
Using 1 part by weight (hereinafter referred to as “part”) and 0.19 part of the silicon compound represented by the above structural formula [4] having an amino group at the terminal group of the organic functional group, a heating reaction is performed at 100 ° C. for 2 hours. It was 84 parts of silica powder was dipped in the obtained product for surface treatment.

The epoxy resin composition was prepared by the following formulation. The surface-treated silica powder obtained under the above conditions was mixed with a biphenyl type epoxy resin (Yuka Kabushiki Kaisha: YX
4000H, epoxy equivalent 195) 3.0 parts, naphthalene type epoxy resin (manufactured by Dainippon Ink and Chemicals: EXA4
750, epoxy equivalent 182) 4.5 parts, phenol novolac resin (manufactured by Mitsui Toatsu Chemicals Inc., as a curing agent,
OH equivalent 180) 5.0 parts, 2-ethylimidazole 0.1 part as a curing accelerator, antimony trioxide 1.6 parts as a flame retardant, silicone oil 0.6 part as a bleeding inhibitor, release agent As a colorant, 0.3 part of natural carnauba and 0.5 part of carbon black as a colorant were mixed and uniformly mixed with a mixer. Then, the mixture was kneaded with a kneader to obtain an epoxy resin composition for sealing.

Example 2 As the silane coupling agent, the same one as in Example 1 was used, and a heating reaction was carried out at 120 ° C. for 1 hour. An epoxy resin composition for encapsulation was obtained in the same manner as in Example 1, except that silica powder was dipped in the obtained product to perform surface treatment.

Comparative Example 1 Silica powder was surface-treated as follows. As a silane coupling agent, a silicon compound represented by the above structural formula [2] having an epoxy group at the terminal group of an organic functional group 0.4
The surface treatment was performed by immersing 84 parts of silica powder. An epoxy resin composition for sealing was obtained in the same manner as in Example 1 except that the above silica powder was used.

Comparative Example 1 Silica powder was surface-treated as follows. As the silane coupling agent, 0.4 part of the silicon compound represented by the above structural formula [4] having an amino group at the terminal group of the organic functional group was used, and 84 parts of silica powder was dipped in the surface treatment.
An epoxy resin composition for sealing was obtained in the same manner as in Example 1 except that the above silica powder was used.

[0027]

[Table 1]

The obtained Examples 1-2 and Comparative Examples 1-2
The moisture resistance of the encapsulating epoxy resin composition was evaluated. The moisture resistance was evaluated by making a sample for evaluation, storing it for a long time in a high humidity state, immersing it in solder, and then determining the degree of cracking of the cured product. First, the obtained epoxy resin composition for encapsulation was molded using a transfer molding machine to prepare five evaluation samples in which semiconductor elements and the like were encapsulated. next,
The above evaluation sample was tested at a temperature of 120 ° C. and a humidity of 100% R.
After being stored in an H 2 atmosphere for 98 hours, it was immersed in a solder bath at a temperature of 240 ° C. for 30 seconds. The cured product was visually observed and the presence or absence of cracks was measured.

As shown in Table 2, the number of cracks was 0 in Example 1, 1 in Example 2, and all 5 in Comparative Examples 1 and 2.

[0030]

[Table 2]

[0031]

When the epoxy resin composition for encapsulation according to claim 1 of the present invention is used, since a thick coupling layer is formed, infiltration of water is small, and thus a sealing having excellent moisture resistance is obtained. A stop layer can be obtained.

Since the semiconductor device according to the second aspect of the present invention is encapsulated with the encapsulating epoxy resin composition, it has good moisture resistance.

Claims (2)

[Claims] 1. A sealing epoxy resin composition comprising an epoxy resin, a curing agent, and surface-treated silica powder as constituent materials, wherein the silica powder is represented by the following general formula [1]: An epoxy resin composition for encapsulation, which is obtained by surface-treating a plurality of silane coupling agents having different organic functional groups with each other by heating and reacting the products. Embedded image Wherein indicates n = 1, 2, 3, R is -CH _3, -CH
₂ CH ₃ and X represents an organic functional group whose terminal group has any one of a vinyl group, a methacrylic group, an epoxy group, an amino group and a mercapto group. ] 2. A semiconductor device which is encapsulated with the epoxy resin composition for encapsulation according to claim 1.