JPH1112344A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition capable of increasing a transmitting rate of a signal, useful for a semiconductor device, etc., and having a high dielectric constant by using each specific epoxy resin and inorganic filter as essential components. SOLUTION: This epoxy resin composition consists essentially of (A) a biphenyl type epoxy resin of formula I, (B) a xylylene type phenol resin of formula II [(n) is 2-31, and (C) an inorganic filler. The component C is alumina and filling amount of the alumina is >=55 vol.%. Preferably, the alumina is used in combination with silica as the component C, the filling amount of the inorganic filler is 60 vol.%, and the proportion of the alumina in the whole inorganic filler is 30 vol.%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an epoxy resin composition having a high dielectric constant and a semiconductor device encapsulated with the epoxy resin composition.

[0002]

2. Description of the Related Art At present, a semiconductor device is driven at a high frequency, so that a signal transmission speed is increased and a loss is large.
Conventionally, an epoxy resin composition used as a sealing material for a semiconductor device has a low linear expansion coefficient of 20 ppm / ° C. or less and good moldability, but has a relative dielectric constant of 3.5 to 4.5. Was. Therefore, the signal transmission speed and the loss are not significantly improved with the increase in the frequency of the semiconductor device.

[0003]

As a result of intensive studies, the inventors have found that an epoxy resin composition as a sealing material for a semiconductor device driven at a high frequency has a high dielectric constant and a relative dielectric constant of 5.0. I found out that it is necessary. The conventional epoxy resin composition as a sealing material has a low relative dielectric constant of 3.5 to 4.5, and does not improve the signal transmission speed or the like even when used for a high-frequency semiconductor device. An object of the present invention is to increase the signal transmission speed by using a high dielectric constant epoxy resin composition.

[0004]

The high dielectric constant epoxy resin composition of the present invention comprises an epoxy resin and an inorganic filler as essential components.

In the present invention, a biphenyl type epoxy resin represented by Chemical Formula 1 is used as the epoxy resin.

In the present invention, the phenolic resin is
Is used.

The inorganic filler used in the present invention is alumina, silicon carbide, or silica. At least one of alumina and silicon carbide is used, and silica is used in combination as needed. A method using alumina as a filler is disclosed in
No. 61-91243, a method using silicon carbide is disclosed in
It is disclosed in Japanese Patent Publication No. 5-67706. This method is for increasing the thermal conductivity of the epoxy resin composition.

The present invention differs from the above-mentioned method in that alumina and silicon carbide are used alone or in combination with silica to limit the filling amount in order to increase the dielectric constant. Silica as the inorganic filler includes fused silica and crystalline silica, and fused silica having a small coefficient of linear expansion is preferable for improving moldability. Alumina and silicon carbide can be used for the purpose of increasing the dielectric constant. Fused silica can be used in combination with these for low thermal expansion. The particle shape may be a sphere or a corner, but a sphere is preferable for improving fluidity.

The epoxy resin composition of the present invention can be obtained by blending the above epoxy resin with an inorganic filler.

Normally, the epoxy resin composition used as a sealing material for a semiconductor device desirably has a linear expansion coefficient of 20 ppm / ° C. or less. The filling amount of the inorganic filler that achieves a relative dielectric constant of 5.0 or more and a linear expansion coefficient of 20 ppm / ° C. or less needs to be 55% by volume or more if alumina is used as the inorganic filler. If alumina and fused silica are used in combination as the inorganic filler, the filling amount of the inorganic filler is 60% by volume or more,
In addition, the proportion of alumina in the entire inorganic filler must be 30% by volume. If silicon carbide is used as the inorganic filler, the amount of the inorganic filler needs to be 50% by volume or more. If silicon carbide and fused silica are used in combination as the inorganic filler, the filling amount of the inorganic filler is 55% by volume.
In addition, the proportion of silicon carbide in the entire inorganic filler needs to be 10% by volume or more.

In the present invention, it is preferable to use a curing accelerator for accelerating the curing reaction between the biphenyl-type epoxy resin and the xylylene-type phenol resin, and the type is not limited as long as it accelerates the curing reaction. For example, phosphorus compounds such as triphenylphosphine, triphenylphosphine / triphenylboron, tetraphenylphosphonium / tetraphenylborate, butyltriphenylphosphonium / tetraphenylborate, and 2-phenyl-4
-Benzyl-5-hydroxymethylimidazole, 2-
Examples of imidazole compounds such as phenyl-4-methyl-5-hydroxymethylimidazole and 2-ethyl-4-methylimidazole, and amine compounds such as 1,8diazabicyclo (5,4,0) undecene-7, diaminodiphenylmethane, and triethylenediamine There is something.

According to the present invention, the surface of the inorganic filler is treated with a coupling agent in advance or a coupling agent is added to the essential components in order to improve the adhesion between the epoxy resin and the curing agent and the inorganic filler. be able to. The surface treatment method and the amount added are not particularly limited. Examples of the type of coupling agent include epoxy silanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N- β- (aminoethyl) -γ-aminopropyltrimethoxysilane,
There are aminosilanes such as γ-aminopropyltriethoxysilane and N-phenyl-γ-aminopropyltrimethoxysilane, and mercaptosilanes such as γ-mercaptotrimethoxysilane. It is preferable to use a silane coupling agent.

In the present invention, an epoxy resin composition and an inorganic filler are essential components, but a releasing agent, a coloring agent, a flexibilizing agent, a flame retardant auxiliary and the like may be added as necessary. The release agent facilitates release from the molding die, and is used alone or in combination with carnauba wax, montanic acid wax, and polyolefin wax. The addition amount is preferably 0.01 to 5% by weight of the total amount. That is, if it is less than 0.01%, there is no effect on the releasability, and if it exceeds 5%, the adhesiveness to a lead frame or a silicon chip is reduced. It is preferable to use carbon black as the coloring agent. The flexibilizing agent compounded for the toughness and low elastic modulus of the cured product is a butadiene / acrylonitrile copolymer having an amino or epoxy group and a carboxyl group terminal which are incompatible with the epoxy resin. A side chain amino group, a hydroxyl group, an epoxy group, a carboxyl group-modified silicone resin demulsifier and the like are used.

The above materials are blended, mixed, kneaded, pulverized and, if necessary, granulated to obtain an epoxy resin composition. The kneading is generally performed by a hot roll, an extruder, or the like.

The semiconductor device of the present invention is one in which a semiconductor element is sealed using the epoxy resin composition obtained as described above. Examples of the sealing method include transfer molding, injection molding, and compression molding. In order to improve the reliability of this semiconductor device, it is preferable to perform after-curing at a temperature of 150 ° C. or higher for a predetermined time after molding with the epoxy resin composition.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

[0017]

[Table 1]

[0018]

[Table 2]

Examples and comparative examples were prepared by blending the respective materials shown in Table 1. Table 1 shows the manufacturing methods of the examples and the comparative examples.
The raw materials were obtained by blending the respective materials in the following manner, mixing, kneading, and pulverizing. Kneading is a biaxial heat roll (65 ° C-85 ° C)
For 10 minutes.

Table 2 shows the characteristics of the epoxy resin compositions and the semiconductor devices of the examples and comparative examples. The production conditions of each test piece were as follows: low temperature transfer press, mold temperature 180 ° C,
It was prepared under the conditions of a molding pressure of 70 kg / cm ² and a molding time of 90 seconds, and was cured by heating at 180 ° C. for 6 hours. The relative dielectric constant was measured according to JIS-C6481. The spiral flow was measured using a mold conforming to the EMMI standard under the conditions of a mold temperature of 180 ° C., a molding pressure of 70 kg / cm ² , and a molding time of 90 seconds. The coefficient of linear expansion was measured using a thermophysical testing machine at a rate of temperature increase of 5 ° C./min. The semiconductor device is molded using the epoxy resin composition by a low pressure transfer press at a mold temperature of 180 ° C., a molding pressure of 70 kg / cm ² , and a molding time of 90 seconds.
For 6 hours.

Example 1 In Example 1, only alumina was used as the inorganic filler, and the filling amount was 60% by volume.
It is.

Example 2 In Example 2, alumina and fused silica were used in combination as an inorganic filler, and the filling amount was 30% by volume of alumina and 30% by volume of fused silica.

Example 3 In Example 3, only silicon carbide was used as the inorganic filler, and the filling amount was 60% by volume.

Example 4 In Example 4, silicon carbide and fused silica were used in combination as inorganic fillers, and the filling amounts were 30% by volume of silicon carbide and 30% by volume of fused silica.

[0025]

The epoxy resin composition of the present invention satisfies the target values of good moldability, a linear expansion coefficient of 20 ppm / ° C. or less, and a relative permittivity of the cured product of 5.0 or more. The element characteristics of the semiconductor device using are good. Therefore, by using as a sealing material of a semiconductor device driven at a high frequency, a reduction in signal transmission speed of the semiconductor device can be prevented.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 23/31

Claims (5)

[Claims] [Claim 1] Embedded image (A) a biphenyl-type epoxy resin represented by Chemical Formula 1,
(B) An epoxy resin composition comprising, as essential components, a xylylene-type phenol resin represented by Chemical Formula 2 and an inorganic filler, wherein alumina is used as the inorganic filler and the amount of alumina is 55% by volume or more. . 2. An epoxy resin composition comprising (a) a biphenyl type epoxy resin represented by the formula (1), (b) a xylylene type phenol resin represented by the formula (2), and an inorganic filler as an essential component, wherein alumina is used as the inorganic filler. An epoxy resin composition comprising a combination of silica and silica, wherein the filling amount of the inorganic filler is 60% by volume, and the proportion of alumina in all the inorganic fillers is 30% by volume. 3. An epoxy resin composition comprising (a) a biphenyl-type epoxy resin represented by the formula (1), (b) a xylylene-type phenol resin represented by the formula (2), and an inorganic filler as an essential component. An epoxy resin composition comprising silicon and having a silicon carbide loading of 50% by volume or more. 4. An epoxy resin composition comprising (a) a biphenyl-type epoxy resin represented by the formula (1), (b) a xylylene-type phenol resin represented by the formula (2), and an inorganic filler as an essential component. An epoxy resin composition containing silicon and silica in combination, wherein the amount of the inorganic filler is 55% by volume, and the ratio of silicon carbide in all the inorganic fillers is 10% by volume. 5. A semiconductor device encapsulated with the epoxy resin composition according to claim 1.