JPH02142821A - Epoxy resin composition - Google Patents

Abstract

PURPOSE:To obtain an epoxy resin composition which can give a cured product of low stress without detriment to moldability and without lowering the Tg and bending strength of a cured product by mixing an epoxy resin with a polyether-modified silicone polymer and a hydrolytic polycondensate of an alkoxysilane. CONSTITUTION:This epoxy resin composition contains the following components A and B as modifiers for lowering the stress of a cured product: a polyether- modified silicone polymer (A) of formula I (wherein R<1> is a 1-4C bivalent hydrocarbon group, and Z is formula II) and a product (B) prepared by hydrolyzing an alkoxysilane and polycondensing the hydrolyzate. The amounts of components A and B added are 0.05-3.00wt.% and 0.5-5.0wt.%, respectively, based on the whole epoxy resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an epoxy resin composition used, for example, for resin encapsulation of semiconductor elements.

[Conventional technology]

Epoxy resin compositions have conventionally been used as adhesives, laminates, semiconductor element sealing materials, and the like in order to construct electronic devices, electronic components, and the like. Especially recently,
For IC in the field of electronics, and even for LS
Demand for I sealing abrasive material is increasing.

In today's semiconductor devices, the size of the chip is increasing as the wiring density increases, but when this large chip is encapsulated with an epoxy resin composition, internal stress of the cured product causes Problems such as shifting (sliding) of aluminum wiring and cracking in the pansivation layer are occurring.

Therefore, attempts have been made to add flexibility to the cured product by adding a common silicone elastomer to the epoxy resin composition, thereby lowering the elastic modulus and relieving the internal stress.

[Problem to be solved by the invention]

However, epoxy resin compositions containing ordinary silicone elastomers have problems such as cracking during molding, a decrease in the glass transition point (Tg) of the cured product, and a decrease in bending strength. It had

Therefore, the inventor first developed a modifier for reducing stress.
A product obtained by hydrolyzing and polymerizing an epoxy resin composition with a polyether-modified silicone polymer (equivalent to A described in the above claims) or an alkoxysilane (as described in the above claims) (Sequentially, patent application No. 10187/1987)
(See specification No. 5, specification of Japanese Patent Application No. 1983-101876)
.

By doing the above, it was certainly possible to achieve the intended purpose of reducing the occurrence of flash during molding and obtaining a cured product with low stress without lowering Tg. However, there was still room for improvement, especially in terms of the bending strength of the cured product.

In view of the above circumstances, it is an object of the present invention to provide an epoxy resin composition that can reduce the stress of a cured product without impairing moldability or reducing the Tg and bending strength of the cured product. The task is to

[Means to solve the problem]

In order to solve the above problems, in the epoxy resin composition according to the present invention, as a modifier to reduce the stress of the cured product,
Make sure that the following (A) and fBl are included.

(A) Polyether-modified silicone polymer A represented by the following general formula (I).

[In the formula, R' represents a divalent hydrocarbon group having 1 to 4 carbon atoms, respectively. (B1 Product B0 obtained by hydrolyzing and condensing alkoxysilanes.) [Function] The epoxy resin composition of the present invention is produced by hydrolyzing polyether-modified silicone polymer A and alkoxysilanes as a modifier. By also containing the product B obtained by condensation polymerization, the internal stress of the cured product can be reduced, and furthermore, it does not cause flaking during molding and decreases the Tg and bending strength of the cured product. It is possible to prevent this from happening.

〔Example〕

The present invention will be explained in detail below.

The epoxy resin composition of the present invention contains at least an epoxy resin, a curing agent for the epoxy resin, and a modifier for reducing stress.

The polyether-modified silicone polymer A has the above general formula (
1), and the side chain is 2 with 1 to 4 carbon atoms.
polyoxyalkylene group Z via a valent hydrocarbon group R'
Contains. When this polymer A is used as a modifier,
The physical properties of the cured product are improved compared to when a polymer containing epoxy groups is used as a modifier.

Repeating number a + b + 1Il in the above formula (1)
l+mg is not particularly limited, but a=2 to 500. b=2~100m1≦20
．． It is preferable that m2≦20°. However, either ml or mg may be O. Here, the above a
, b below the above range, performance such as moldability and low stress physical properties of the cured product may not be improved. Furthermore, if at least one of a, bnl+, and mg exceeds the above range, there is a risk that performance such as moldability and low stress physical properties of the cured product may deteriorate.

The proportion of polyether-modified silicone polymer A to be added is not particularly limited, but the proportion of polyether-modified silicone polymer A in the entire epoxy resin composition is 0.
A range of 0.05 to 3.00% by weight is preferred. If it is less than 0.05% by weight, the effect of reducing stress in the cured product may not be achieved. On the other hand, if it exceeds 3% by weight, the Tg of the cured product
There is a risk that the strength may decrease or firmness may occur during molding.

Product B obtained by hydrolyzing and polycondensing alkoxysilanes can be produced, for example, as follows, but this is an example of a production method, and it goes without saying that it may be synthesized by any other method. stomach. First, zero alkoxysilanes.
．． 1 to 5.0 equivalents of purified water and an appropriate amount of a water-soluble solvent for dissolving the alkoxysilanes (i.e., enough to dissolve the alkoxysilanes) are added and dissolved.
Stir and react at 80°C for about 1 hour to about 2 days. In this case, the lower the reaction temperature, the longer the reaction time. Thereafter, the desired product B is obtained by removing the water-soluble solvent and water using an evaporator or the like.

A more detailed reaction example will be described below using γ-glycidoxypropyltrimethoxysilane as an example.

↓+1ho (hydrolysis) ↓-■20 (condensation polymerization) 0-3i ・ ・ ・ Product B produced by the reaction as described above was found to have peak broadness and S
Since it can be seen that functional groups other than the alkoxy bonded to i remain, it can be assumed that it is a hydrolyzed/condensed product of alkoxysilanes, and liquid chromatography analysis shows that it has been polymerized. can be inferred.

The reason why alkoxysilanes are used by hydrolyzing and polycondensing them is that polymerization lengthens the chain between the inorganic substance such as silica and the resin, lowering stress and relieving stress. This is because it is effective.

Examples of alkoxysilanes include ■γ(2-aminoethyl)aminopropyltrimethoxysilane, ■T
-(2-aminoethyl)aminopropylmethyldimethoxysilane, ■γ-methacryloxypropyltrimethoxysilane, ■γ-glycidoxypropyltrimethoxysilane, ■γmercaptopropyltrimethoxysilane, ■methyltrimethoxysilane, ■methyl Triethoxysilane, ■vinyltriacetoxysilane, ■γ-anilinopropyltrimethoxysilane, [phase] vinyltrimethoxysilane, 0γ-mercaptopropylmethyldimethoxysilane, etc. are used alone or in combination of two or more. . As the alkoxysilane, it is preferable to use one that does not contain chlorine, in view of improving the moisture resistance of the cured product. The structural formulas of the compounds (1) to (2) above are shown below.

■ NH, CIl, CII□NICII□GHzCHz
St (OCHs) *■ NLCLCH2NHC112
CH1C112Si (OCRl)2CH1■ CHz
=CCHsCOOCH−CHtCHtSi (OCR2
) −■ H3CH2CH2CII□5i (OCIIs
)s■ CI(*Si(,0CHs)* ■ CH-3t(OCR-COx)* ■ CHz=CI(-Si(OCOCR-)-[phase]
CHg=C)l-5i(OCL)x(Dl5CHz
C1 (zcHzsi (OCIIs) 1CII-As the water-soluble solvent, for example, metal chloride, ethanol, acetone, etc. are used.

The product B obtained by hydrolyzing and condensing alkoxysilanes is preferably 0.5 to 5.0% by weight of the entire epoxy resin composition. If it is less than 0.5% by weight, the effect of low stress physical properties may not be obtained. On the contrary, 5.0
If the amount exceeds % by weight, the Tg of the cured product may decrease or problems may arise in moldability.

Examples of the epoxy resin used in the present invention include bisphenol A epoxy resin, bisphenol F epoxy resin, novolak epoxy resin, alicyclic epoxy resin, and the like, but are not particularly limited. These may be used alone or in combination. However, when using the epoxy resin composition of the present invention as a molding material for sealing a semiconductor element or the like, it is preferable to use a novolac-based epoxy resin in view of physical properties such as Tg and moisture resistance of the cured product.

As the curing agent, for example, phenol novolak resin, acid anhydride, amines, etc. can be used alone or in combination. For the same reason as in the case of the epoxy resin described above, it is preferable to use a phenol resin such as a phenol novolac resin as the curing agent, but the curing agent is not limited thereto. Further, there is no particular restriction on the blending ratio of the curing agent, and the necessary amount may be set as appropriate.

The epoxy resin composition of the present invention containing the essential components described above may further contain one or more of the following other components, if necessary. Examples of the same components include hardening aids or hardening accelerators (tertiary amines, imidazoles, organic phosphorus compounds, etc.), fillers or reinforcing materials (silica powder, alumina powder, calcium carbonate powder, glass fibers, etc.).

carbon fiber, etc.), N fuming agent (antimony trioxide, brominated epoxy resin, hydrated alumina, etc.), mold release agent (wax, stearic acid, stearate, etc.), coloring agent (carbon blank, metal oxide, etc.) pigments), but the types and blending ratios thereof are not particularly limited. In addition, when using a filler, it is preferable to set it so that it may be 10-80 parts with respect to 100 parts by weight (hereinafter simply referred to as "parts") of the entire epoxy resin composition. By adding 10 parts or more of filler, it is possible to reduce the linear expansion coefficient and maintain good heat dissipation.
If the amount exceeds 0 parts, the cavity may not be completely filled and moldability may deteriorate.

By mixing the above components (essential components and other components if necessary) using a mixer, blender, etc., and kneading them using a kneader, rolls, etc., epoxy resin as a molding material is produced. A composition can be obtained. After kneading, if necessary, the mixture may be cooled to solidify and pulverized to form granules or the like. In addition, the above modifier A, 82 types,
It may be mixed in advance with a hot-molten epoxy resin or a hardening agent (phenol resin, etc.), and then mixed with other components. This is preferable because the modifier and the resin can be mixed uniformly.

More detailed examples of the present invention will be shown below together with comparative examples, but the invention is not limited to the following examples.

Examples 1-3, Comparative Example 1.2 The following two types of modifiers A and B.

A: Polyether modified silicone polymer; (a = 2
00. b=20. m+=mz=5)B:(
7) γ-mercaptopropylmethyldimethoxysilane,
Using each hydrolysis/condensation product of (a) γ-(2-aminoethyl)aminopropyltrimethoxysilane or (1) γ-glycidoxypropyltrimethoxysilane, an epoxy resin consisting of the following components is prepared. A resin composition was prepared. In addition, the above B includes 50 parts of each raw material alkoxysilane, 50 parts of purified water, and 50 parts of metalul.
After adding and melting 1 part, the reaction was carried out at a reaction temperature of 50° C. for 6 hours in cases (ke) and (ii), and for 15 hours in case (a).

★Epoxy resin composition (numbers represent compounding parts) Here,
The above components were blended according to the following procedure. First, modifiers A and/or B were added to the epoxy resin heat-melted at about 120° C. and mixed uniformly with a high-speed disperser for about 10 minutes. Thereafter, it was cooled and finely pulverized, and the resulting finely pulverized powder was combined with the other components mentioned above, mixed in a mixer, and kneaded using a kneader to obtain a molding material.

The same molding material was processed according to the usual method at a pressure of 50 kg/mj and a temperature of 1.
It was molded at 70°C for 3 minutes and after-cured at 170°C for 5 hours.

Comparative Example 3 None of the above modifiers were used, and the filler content was 70%.
．． A cured product was obtained by processing in the same manner as above except that the amount was changed to 6 parts.

For each of the epoxy resin compositions of the above Examples and Comparative Examples, the occurrence of flakes during molding, coefficient of linear expansion (α, ), flexural modulus (E), flexural strength (σf), and Tg were investigated.
Furthermore, a heat cycle test was conducted.

The occurrence of firmness during molding was determined by observing the presence (x) and absence (○) of 10 to 100 μl of seepage from between the mold slits, and ○,
Evaluation was made with × and △. The linear expansion coefficient and Tg were determined by the TMA method, and the flexural modulus and flexural strength were measured using a flexural strength tester. Heat cycle test is ΔT=
A heat cycle temperature test was performed at a temperature of 200° C., and the results were evaluated as excellent (◎), good (○), and bad (×).

The above results are also shown in Table 1.

As shown in Table 1, compared to the comparative example, the example has no occurrence of flash, Tg and bending strength σf have not decreased, and the linear expansion coefficient α1 and bending modulus E have further decreased. . In other words, the stress is reduced. Further, the heat cycle test results of the examples were also very good.

〔Effect of the invention〕

As described above, the epoxy resin according to the present invention is less likely to generate flakes during molding, and can provide a cured product with low stress without reducing the Tg and bending strength of the cured product.

Agent: Patent Attorney Takehiko Matsumoto

Claims (1)

[Claims] 1. The following (A) is used as a modifier for reducing stress in a cured product:
Epoxy resin composition (A) containing and (B)
A polyether-modified silicone polymer A represented by the following general formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) [In the formula, R^1 is a divalent hydrocarbon group having 1 to 4 carbon atoms, Z
▲There are mathematical formulas, chemical formulas, tables, etc.▼, respectively. ] (2) Product B obtained by hydrolyzing and polycondensing alkoxysilanes.