JPS61101521A - 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 nonionic surfactant and an inorganic filler as essential components. CONSTITUTION:The purpose sealing resin composition is formed by using an epoxy resin, a novolak phenolic resin, 0.02-5wt% nonionic surfactant (e.g., polyoxyethylene alkyl ether or polyoxyethylene sorbitan alkyl ester) 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 free from unfilled part and deformation of bonding wire can be obtained by molding with the above rein composition by, for example, low-pressure transfer molding.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a sealing resin composition that is less likely to cause flashing and has excellent fluidity.

[Technical background of the invention and its problems 1 Currently, resin encapsulation using low-pressure transfer molding using epoxy resin or silicone resin is a common method for encapsulating semiconductor elements such as diodes, transistors, and integrated circuits. is being carried out.

The reasons for this are (1) improved reliability due to improvements in sealing resin and advances in passivation technology; (2)
) The material costs are relatively low and mass production is good. However, ff due to low pressure transfer molding i
In order to achieve the benefits of i-products, it is necessary to increase the number of products produced per molding shot, and in recent years, molding machines and molds have become larger and larger, with the aim of producing a large number of products. It's coming. Along with this, the requirements for the sealing resin have become even more stringent, such as (a) good fluidity and no unfilling, and (0) low melt viscosity and no deformation of the positive wire. (3) It has become necessary to have no problems with regard to moldability, such as a small amount of resin particles generated in the wood frame.

However, there is a tendency for the fluidity and melt viscosity of the sealing resin to conflict with the amount of resin debris generated on the joint surfaces of lead frames and molds. For example, increasing the amount of resin or using a resin with low viscosity improves fluidity. However, resin debris is more likely to occur as the fluidity improves (this makes it more difficult to remove resin debris from lead frames, etc., and debris adhering to molds can impair the precision of the mold). On the other hand, resin spalling can be suppressed to a certain extent by using a method opposite to the above-mentioned 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 increased melt viscosity resulting in deformation of the bonding wire.

[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 intensive research to achieve the above object, the present inventor adds a nonionic surfactant.

It has been found that the resin composition has less occurrence of resin flakes and has good fluidity, thus achieving the above objectives and being suitable for a resin composition for sealing. That is, the present invention provides a sealing resin composition characterized by having (A) an epoxy resin <8> a novolac type phenol resin, (C) a nonionic surfactant, and (D) an inorganic filler as essential components. It is a thing.

The epoxy resin used in the present invention (A> Epoxy resin is not particularly limited in molecular structure, molecular weight, etc., as long as it is a compound having at least two epoxy groups in its molecule, and includes a wide range of commonly used resins. Examples include aromatic resins such as bisphenol type, 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.

(B) novolac type phenol resin used in the present invention and q
Examples include novolak phenolic resins obtained by reacting phenols such as phenol and alkylphenols with formaldehyde or paraformaldehyde, and modified resins thereof, such as epoxidized or butylated novolak phenolic resins, which may be used alone or in combination. It is used by mixing more than one species.

As the nonionic surfactant (C) used in the present invention,
There are no particular restrictions and all nonionic surfactants can be used, but especially +0CH2+,..., 10CH2CH2+, +0CH2 in the molecule.
CH, CH2+. A polyoxyalkylene compound having a polyoxyalkylene bond such as the following is desirable. Specific compounds include R-0→C2H, O←H n polyoxyethylene alkyl ethers polyoxyethylene alkylphenol ethers R-Coo-+C,
H, O←H Polyoxyethylene alkyl esters, polyoxyethylene sorbitan alkyl esters, polyoxypropylene alkylamine.

- Polyoxyethylene alkylaroid (where R in the formula: Cn H2n++, n represents an integer of 1 or more), etc., and these may be used alone or in a mixture of two or more. The amount of nonionic surfactant to be blended is not particularly limited, but it must be contained in an amount of 0.02 to 5.0% by weight based on the resin composition. If it is less than 0.02 mm%, it will not be effective in reducing resin flakes or improve fluidity, and if it exceeds 5% by weight, it will increase the cost, 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 white, clay, asbestos, mica, red iron, glass fiber, carbon glue M, etc. They may be used alone or in a mixture of two or more. Among these, silica powder or alumina is particularly preferred. The blending amount of the inorganic filler is 30 to 901jl'% based on the resin composition.
It is necessary to contain If it is less than 30% by weight or more than 1% by weight, 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) nonionic surfactant, and (D) inorganic filler are essential components, but if necessary, for example, natural waxes, synthetic waxes, etc.
Metal salts, acid amides, or esters of straight chain fatty acids,
M-type agents such as paraffins, flame retardants such as chlorinated paraffin, pumtoluene, hexaprobenzene, antimony trioxide, colorants such as carbon black and red iron, silane coupling agents, various curing accelerators, etc., as appropriate. Can be added and blended.

A general method for preparing the sealing resin composition of the present invention as a molding material is to mix the above-mentioned epoxy resin, novola, resin-type phenolic resin, nonionic surfactant, inorganic filler, etc. 1, and this molding material I
! Applicable to the sealing, coating, insulation, etc. of hand parts or electrical parts, giving them excellent characteristics and reliability.
-6, , ゛ [Effects of the invention] ``The resin composition for clay of the present invention has less greenness and excellent fluidity, so it can be molded by low-pressure transfer molding etc. By doing so, it is possible to obtain a reliable molded product with no unfilled parts and no deformation of the bonding wire.

゛ [Examples of the Invention゛]' The present invention will be explained in detail with reference to Examples, but the present invention is not limited to the following Examples.

In the following Examples and Comparative Examples, "%" means 11
means %J.

Example 1 Cresol novolak epoxy resin (epoxy weight @ 2
15) 18%, novolac type phenolic resin 10%,
1% polyoxyethylene alkylphenol ether represented by the following formula, 10% silica powder, ' and 1% higher fatty acid ester were mixed at room temperature, further cross-cooled at 90 to 95°C, and then crushed to obtain a molding material. .

Viscosity, i-dynamics, generation of resin particles when molded products are made by transformer molding, mechanical properties,
The glass transition point and moisture resistance were tested. The results are shown in Table 1.

Example 2 A molding material was prepared in the same manner as in Example 1 except that 1% of polyoxypropylene alkylamine represented by the following formula was added in place of the polyoxyethylene furkylphenol ether of Example 1.

The viscosity and fluidity of the resulting molding material, the occurrence of resin particles when molded products are made by transfer molding, mechanical properties,
The glass transition point and moisture resistance were tested. The results are shown in Table 1.

Comparative Example Cresol novolak epoxy resin (epoxy
215) 18%, novolac type phenolic resin 10%
, 11% of silica powder, and 1% of higher fatty acid ester were added, and a molding material (q) was prepared in the same manner as in Example 1. The occurrence of resin flakes, mechanical properties, glass transition temperature and moisture resistance were tested.The results are shown in Table 1.

Table 1 *1: Exposure to εMMI-1-66 *2: Measurement of the quality of flow through a 10μ slit groove -4:3: Electrical component with two aluminum wirings made using molding material at 170mm Transfer molding was carried out at 180'C for 3 minutes, followed by curing at 180'C for 8 hours. The 100 sealed electrical components thus obtained were subjected to a moisture resistance test in high-pressure steam at 120° C., and the time required for 50% disconnection (defect occurrence) due to aluminum corrosion was evaluated.

Claims (1)

[Scope of Claims] 1. A sealing resin composition characterized by having (A) an epoxy resin, (B) a novolac type phenolic resin, (C) a nonionic surfactant, and (C) an inorganic filler as essential components. thing. 2. The sealing according to claim 1, wherein the nonionic surfactant is a polyoxyalkylene compound and is contained in an amount of 0.02 to 5.0% by weight based on the resin composition. Resin composition for use. 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.