JPS61101519A - Epoxy molding material for sealing electronic part - Google Patents

Abstract

PURPOSE:The titled molding material having a low stress value against an insert and containing fine silicon polymer powder treated with a silane coupling agent. CONSTITUTION:Fine silicone polymer powder (e.g., polydimethylsiloxane) of a particle diameter <=500mum and a glass transition temperature <= room tempera ture is mixed with 1-40wt% silane coupling agent (e.g., gamma-glycidoxypropyltri methoxysilane) at 120-150 deg.C for 1-5hr to obtain a fine silicon polymer powder treated with the coupling agent. An epoxy resin is mixed with 0.1-10wt% said fine polymer powder, a curing agent, a cure accelerator, a filler, a colorant, a flame retardant, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to an epoxy molding material for encapsulating electronic components, which has a small stress value on inserts and has excellent moisture resistance and heat resistance.

[Conventional technology]

Traditionally, coils, capacitors, and transistors.

Epoxy molding materials are widely used as encapsulants for electronic components such as ICs. The reason for this is that the epoxy resin has a good balance in various properties such as electrical properties, heat resistance, mechanical strength, and adhesion to inserts.

[Problem that the invention seeks to solve]

However, there is a trend toward smaller and thinner packages, as typified by UIC packages for electronic components, which causes the problem of packages cracking during cooling and heating cycles. This is caused by thermal stress generated between the insert and the molding material for sealing due to the temperature difference. This thermal stress also has an adverse effect on insert products, causing malfunctions in large devices such as LSIs. Various problems arise with conventional epoxy molding materials when fire forming fcTIt child parts with smaller and thinner packages and larger inserts. It is strongly desired to have a small thermal stress value (
・Ru.

The present invention modifies the hard and brittle properties of epoxy resin with a specific silicone polymer to obtain a molding material for inserts with low stress and excellent heat resistance and 5M humidity.

[Means for solving problems]

The epoxy resin molding material for encapsulating electronic components of the present invention is characterized in that the epoxy resin contains 0.1 to 10% by weight of silicone polymer fine powder treated with a silane coupling agent. The elastic modulus of the part at room temperature can be reduced,
The thermal stress value for insert products can be greatly reduced. Due to this, actual FP (flat package) type I
The package crack resistance due to C can also be significantly improved.

The epoxy resins used in the present invention include general epoxy resins such as 2-enol novolac type, bisphenol A type, and bisphenol F type, and alicyclic epoxy resins such as vinylcyclohexene dieboxide.
It's not something you can do. Hardening agents include organic polyamines such as aliphatic amines and aromatic amines, urea resins, and melamine.
Amino acids such as shea, aniline and aniline, complex amine compounds such as dicyandiamide and xylylene diamine, phthalic acid, hexahydrophthalic acid, tetrahydrophthalic acid, and trimellitic acid.

polycarboxylic acids and acid anhydrides such as pyromellitic acid,
Phenolic resins such as phenol novolac resin, cresol novolac resin, resorcinol novolac resin,
Bisphenol A, polyparavinylphenol resin, etc. are included.

Imidazole, 5th class amine, BFI as curing accelerator
A small amount of -7mine complex organic phosphine or the like can be used in combination. In addition, the filler 'C' is silica, quartz glass powder, calcium carbonate, calcium silicate, alumina, aluminum hydroxide, magnesium hydroxide, clay, mica, glass fiber, and various single crystal fibers.
40 to 7Q volume % is used for L resin.Other additives include higher fat In% higher fatty acid metal salt, quasi-forming agent such as ester wax, coloring agent such as carbon black, flame retardant, A surface treatment agent or the like can be used.

The ef feature of the present invention is that 0.1 to 10% by weight of silicone polymer fine powder treated with a silane coupling agent is added to the epoxy resin composition. Electronic components such as ICs and transistors? :Pj, the gate size of the mold to be formed is generally about 15 to 1ffIft+, and the large diameter of the silicone polymer added to the molding material is also preferably 500 μm or less. Considering the deformation of the bonding wire connecting the leads, the
m or less is preferable. As a silicone polymer.

High performance polyorganosiloxanes such as polydimethylsiloxane, polymethylphenylsiloxane, and dimethylsiloxane-diphenylsiloxane copolymers are listed.
Ru. Furthermore, crosslinked products of these polyorganosiloxane polymers may also be used. The physical properties of silicone polymers are not particularly limited, but the normal molding temperature is 150°C.
Preferably, it maintains its particle shape without causing flow at temperatures between 180°C and 180°C. In addition, for stress reduction and crack resistance, the glass transition temperature of the silicone polymer is preferably room temperature or lower.

The treatment of the silicone polymer is carried out by premixing the silicone 1 combined fine powder with the silane coupling agent 1, treating the surface of the silicone fine powder, and treating the preliminary mixture with P.

If the silicone polymer content is less than 0.1% by weight, the effect will be small, and if it exceeds 101% by weight, the strength will decrease.

Also, if silicone fine powder is simply blended into the epoxy resin composition and kneaded with a roll extruder to create a molding material, there will be a lot of flakes during molding.

Regarding the silane coupling agent used in the present invention (・
Although not particularly limited, there are reactive groups such as methoxy groups, ethoxy groups, and silanol groups that chemically bond with inorganic substances, and epoxy groups, amino groups, mercapto groups, and vinyl groups that chemically bond with resin systems on the other hand. An organosilicon monomer having a reactive group such as a methacrylic group is used. Its distribution
is used in an amount of 1 to 40% based on the C-cone heavy body powder.

Further, as a pre-mixing method, there is a method in which a silane coupling agent is diluted with a solvent such as water or alcohol, and a silicone polymer is mixed therein. There is a method of mixing using a Henschel mixer or the like without a solvent, but the latter method is also sufficiently effective as it is easier to work with. Further, the temperature of the Nakasho treatment is not particularly limited, but it is preferably heated at 120° C. to 150° C. for 1 hour to 5 hours.

〔Example〕

The present invention will be explained below with reference to Examples, but the scope of the present invention is not limited to these Examples.

Epoxy Ji220. Cresol novolak type epoxy resin with a softening point of 78°C, epoxy equivalent weight 375, softening point 80
°C, brominated II 48 w% brominated bisphenol A
Type epoxy resin, hydroxyl equivalent weight 106. A phenol novolac resin with a softening point of 83°C, 2-heptadecyl imidazole, carnauba wax, antimony trioxide, carbon black, γ-glycidoxyprobyltrimethoxysilane, quartz glass powder, and the treatments shown in Table 1 were used. Polydimethylsiloxane fine powder with a diameter of 250 μm or less was distributed in the composition shown in Table 2, and a comparison was made using a 10 inch diameter heating roll at a crosstalk temperature of 80 to 90°C and a crosstalk time of 7 to 10 minutes. Examples (1) to (3), Examples (1) to (2)
An epoxy molding material was created. Table 3 shows the properties of the molding materials of Comparative Examples and Examples. Further, details of the characteristic evaluation method shown in Table 3 are shown in Table 4. From Table 3, for Comparative Example (1) in which no silicone polymer fine powder was added.

In Examples (1) to (2), the bending elastic modulus at room temperature is reduced and the stress value is accordingly reduced.

Further, it can be seen that the degree of reduction in stress value 8 depends on the addition 'P#. Here, if we look at Rebelta in Paris, we see comparative examples (2), (3 n,
(5) is worse than Comparative Example (1), but Example (1) created by Processing Method A has no drop in Paris level, and Example (2) created by Processing Method B is worse than Comparative Example (1). ) got better results.

In order to further clarify the effects of the present invention, the results of a thermal shock test of an FP (flat package) type IC will be shown. The size of the FP used for this evaluation is 19 x f 4 x t
It is equipped with a 5t (am) 6'), 6 x 6 (mm) element, 7t54 pin, and 4.2 alloy lead. The test conditions were immersion in silicone oil at 150°C and liquid nitrogen at -196°C for 2 minutes each, making one cycle.

Evaluation was made by observing the external appearance under a microscope and determining the presence or absence of package cracks. In addition, FP molding was carried out under the conditions of 1sa"c, 9a seconds, 70kg/arp, and 180℃ after molding.
It was post-cured for 5 hours.

Table 5 shows the thermal shock test results. Table 5 shows that the package cracking property can be greatly improved by adding silicone polymer fine powder.

〔effect〕

The epoxy molding material for encapsulating electronic components obtained by the present invention has a small thermal stress value, a large element size, and the VLSI products and packages that are easily damaged by the stress of the encapsulating molding material are thin and small. , FP (flat package), which requires package crack resistance, 5O
It can be widely applied to products such as P (Small Outline Package), and there are few Paris (・.

1-7-11 Procedural amendment (method) % formula % 1. Indication of the case 1982 Patent Application No. 225574 2. Name of Q Ming Epoxy molding material for sealing electronic parts 3. Person making the amendment Case and Relationship with Patent Applicant Name (4451 Hitachi Chemical Industry Co., Ltd. 4, Agent)

Claims (1)

[Scope of Claims] 1. An epoxy molding material for encapsulating electronic parts, which contains 0.1 to 10% by weight of silicone polymer fine powder treated with a silane coupling agent. 2. The epoxy molding material according to claim 1, wherein the silicone polymer fine powder is premixed with a silane coupling agent. 3. The epoxy molding material according to claim 1, wherein the silicone polymer fine powder is premixed with a silane coupling agent and then heat-treated.