JPS61101520A - Sealing resin composition - Google Patents

Abstract

PURPOSE:A semiconductor-sealing resin composition which scarcely forms fins and is excellent in flow, containing an epoxy resin, a novolak phenolic resin, a silicon oil of a specified composition and an inorganic filler as essential components. CONSTITUTION:The purpose sealing resin composition is formed by using an epoxy resin, a novolak phenolic resin, 0.01-5wt% silicon oil comprising a silicon/polyalkylene oxide copolymer [e.g., a compound of formula I (wherein Y is a group of formula II, R is a group of formula III and l, m and n are each at least 1] and 30-90wt% inorganic filler (e.g., silica powder or alumina) as essential components. If desired, a mold release, a colorant, etc., may be added to the composition. A molding freed from unfilled part and deformation of bonding wires can be obtained by molding with the above resin composition by, for example, low-pressure transfer molding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention provides a resin composition for sealing with less generation of paris and excellent ft mobility.

[Technical background of the invention and its problems] Currently, resin encapsulation by low-pressure transfer molding using epoxy resin or silicone resin is generally used as a method for encapsulating semiconductor elements such as diodes, transistors, and integrated circuits. It is being said.

The reasons for this are (1) improved IJ reliability due to improvements in sealing resin and advances in passivation technology;
2) The material cost is relatively low, and the R productivity is good. Low voltage transformer 7? - In order to achieve the benefits of mass production through molding, the number of products that can be removed per molding shot has been increased, and in recent years, molding machines and molds have become increasingly larger, and the trend has been to create multiple products. It has become to.

Along with this, the requirements for sealing resins have also become stricter.
For example, (a) good fluidity and no unfilling; (b)
Low melt viscosity and no deformation of the bonding wire,
(c) Lead frames have been required to have no problems with moldability, such as less resin particles.

However, there is a tendency for the fluidity and melt viscosity of the sealing resin to conflict with the appearance of resin flakes on the joint surfaces of lead frames and molds. For example, fluidity can be improved by increasing the amount of resin or using a resin with low viscosity. However, the occurrence of resin particles increases as fluidity improves.
For this reason, there is a drawback that it takes time and effort to deal with the dust buildup on the lead frame, etc., and the dust attached to the mold impairs the accuracy of the mold. On the other hand, resin spalling can be suppressed to a certain extent by using a method opposite to the above-described method or by considering the particle size distribution of the inorganic filler. However, attempts to suppress the occurrence of resin flakes have had many drawbacks, such as poor fluidity resulting in unfilling, and deformation of the bonding wire as the melt viscosity increases.

[Object of the invention] The object of the present invention has been made in view of the above drawbacks, and
It is an object of the present invention to provide a sealing resin composition that is less likely to generate resin flakes and has excellent fluidity.

[Summary of the Invention] As a result of repeated research in order to achieve the above object, the present inventor found that adding a specific silicone oil reduces the occurrence of resin flakes and improves fluidity, thereby achieving the above object. The inventors have found that the present invention is suitable for use in sealing resin compositions. That is, the present invention is characterized in that (A) an epoxy resin <8) a novolak type phenolic resin, (C) a silicone oil made of a copolymer of silicone and polyalkylene oxide, and (D) an inorganic filler as essential components. This is a sealing resin composition.

The epoxy resin used in the present invention (A>Epoxy resin is a compound having at least two epoxy groups in its molecule, and is not particularly limited in molecular structure, molecular weight, etc.), and includes a wide range of commonly used resins. Examples include aromatic hisphenol type resins, alicyclic resins such as cyclohexane derivatives, and epoxy novolak resins represented by the following general formula.

(However, in the formula, R1 represents a hydrogen atom, a halogen atom, or an alkyl group, R2 represents a hydrogen atom or an alkyl group, and n represents an integer of 1 or more.) These epoxy resins may be used alone or in combination of two or more. can be used.

The novolak phenolic resin (B) used in the present invention includes novolak phenol resins produced by reacting phenols such as phenol and alkylphenols with formaldehyde or paraformaldehyde, and modified resins thereof, such as epoxidized or butylated resins. Examples include novolac type phenolic resins, which may be used alone or in combination of two or more.

The silicone oil (C) made of a copolymer of silicone and polyalkylene oxide used in the present invention includes:
There are no particular limitations on the structure of the original silicone, the type of functional group, the number of carbon atoms in the polyalkylene oxide, etc. Specific examples include compounds having the following structural formulas.

-R-COOI7 -R-NH2, -R-OH, -R-
C.N.

R: →CH2←.

R′　Co　H,C)-13 or an alkyl group.

(1 is an integer greater than or equal to 0, l and n are integers greater than or equal to 1, respectively)) There is no particular restriction on the amount of silicone oil made of a copolymer of silicone and polyalkylene oxide, but the amount is 0. It is necessary to contain 01 to 5.0% by weight. If o, o is less than 1% by weight, it will have no effect on reducing resin spall or fluidity;
If it exceeds 1%, the cost will increase, which is not preferable. Therefore, it is necessary that it be within the above range.

Examples of the inorganic filler (D) used in the present invention include silica powder, alumina, antimony trioxide, talc, calcium carbonate, titanium oxide 1~, clay, asbestos, mica, red iron, glass fiber, carbon fiber, etc. Or a mixture of 211 or more is used. Among these, silica powder or alumina is particularly preferred. The amount of the inorganic filler to be blended must be 30 to 90% based on the acid. Less than 30% by weight or 9
If the temperature exceeds 0, the moldability is poor and it is not suitable for practical use.

The sealing resin composition of the present invention comprises (A) an epoxy resin, (
B) novolak type phenolic resin, (C) silicone oil, and (D) inorganic filler are essential components, but if necessary, for example, natural waxes, synthetic waxes, straight chain fatty acid gold, 9142, acid amide, or Mold release agents such as esters or paraffins, flame retardants such as chlorinated paraffin, bromotoluene, hexabromobenzene, and antimony trioxide, colorants such as carbon black and red iron oxide, silane coupling agents, various curing accelerators, etc. can be added and blended as appropriate.

As a general method for preparing the sealing resin composition of the present invention as a molding material, the above-mentioned epoxy resin A resin,
Novolac-type phenolic resin, silico, oil, inorganic filler, etc. are blended, and the fusuma is thoroughly and uniformly mixed with a mixer, etc., and then melted and mixed with hot rolls, or mixed with a kneader, etc., and then cooled and solidified as appropriate. It can be crushed to a large size and used as a molding material.

This molding material can be applied to sealing, covering, insulating, etc. electronic or electrical components to impart excellent properties and reliability.

[Effects of the Invention] The encapsulating resin composition of the present invention has less occurrence of resin flakes and has excellent fluidity, so when molded by low pressure, transfer molding, etc., it can be used to form bonding wires without unfilled parts. A highly reliable molded product without deformation can be obtained.

[Embodiments of the invention]

EXAMPLES The present invention will be specifically explained with reference to Examples, but the present invention is not limited to the following Examples.

In the following Examples and Comparative Examples, "%J" means "M
m%".

Example 1 Cresol novolak epoxy resin (121
5) Mix 18%, novolak type phenolic resin, 1% silicone oil (viscosity 1200 centistokes) shown by the following formula, 10% silica powder, and 1% higher fatty acid ester at room temperature, and give a roughness of 90 to 95%. After kneading and cooling at °C, the mixture was pulverized to obtain a molding material.

(However, during the ceremony R: →CH2←.

Jl, ta, and n each represent an integer on the 1st scale)
The viscosity, fluidity, transfer, etc. of the obtained molding material
When a molded article was made by molding, the occurrence of resin flakes, K mechanical properties, glass transition point, J5, and moisture resistance were tested. The results are shown in Table 1.

Example 2 A molding material was obtained in the same manner as in Example 1 except that 1% of an epoxy-modified silicone oil (viscosity: 3000 centistokes) represented by the following formula was added in place of the silicone oil in Example 1.

(However, during the ceremony 1pe, →CH2←.

R': H or alkyl group.

7, m and n each represent an integer greater than or equal to 0) (viscosity, strength, fluidity of the molding material, light weight of the resin when molded products are made by transfer molding, low range characteristics) , glass transition point, and moisture resistance were tested.The results are shown in Table 1.

Example 3 Silicone oil (viscosity 2000 centistokes) 1 represented by the following formula was used instead of the silicone oil of Example 1.
A molding material was obtained in the same manner as in Example 1 except that % was added.

(However, in the formula, z, m, and n do not represent integers greater than or equal to 0.) The viscosity, fluidity, and transferability of the obtained molding material. - Occurrence of resin flakes when made by molding, mechanical properties, glass transition point,
and moisture resistance were tested.

The results are shown in Table 1.

Comparative Example Cresol Novolac (1 fat epoxy fi 215
) 18%, novolac type epoxy resin 10%, silica powder 71%, d3 and higher fatty acid ester 1% in Example 1
A molding material was obtained in the same manner as above. The resulting molding material was tested for viscosity, fluidity, occurrence of resin flakes when made by transfer molding, mechanical properties, glass transition point, and moisture resistance. The results are shown in Table 1.

Table 1: l:l: Based on EMMl-1-66:):2;
Measure the length of Paris flowing through the 10 μm slit groove *3
: Using the molding material, an electrical component having two aluminum wirings was transfer molded at 170°C for 3 minutes, and then cured at F2180°C for 8 hours. A moisture resistance test was conducted in high-pressure steam at °C, and the time required for 50% wire breakage (defect occurrence) due to aluminum corrosion was evaluated.

Claims (1)

[Scope of Claims] 1. It is characterized by having (A) an epoxy resin, (B) a novolak type phenolic resin, (C) a silicone oil made of a copolymer of silicone and polyalkylene oxide, and (D) an inorganic filler as essential components. A sealing resin composition. 2 Silicone oil consisting of a copolymer of silicone and polyalkylene oxide is 0.01 to 5% of the resin composition.
．． The sealing resin composition according to claim 1, characterized in that it contains 0% by weight. 3. The sealing resin composition according to claim 1 or 2, wherein the inorganic filler is contained in an amount of 30 to 90% by weight based on the resin composition.