JP3125059B2 - Epoxy resin composition for sealing electronic parts - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic component such as a semiconductor device which is excellent in moldability such as rapid curability and fluidity and gives a cured product excellent in mechanical strength, heat resistance and crack resistance. The present invention relates to an epoxy resin composition for sealing.

[0002]

2. Description of the Related Art A resin composition containing an epoxy resin as a main component is widely used in electric and electronic fields such as casting, sealing, and laminates. In recent years, as electronic components have become smaller and thinner,
A lower viscosity epoxy resin composition is desired. Conventional epoxy resin compositions often have relatively high viscosity, which causes molding defects such as resin not completely flowing into minute gaps between parts or entrapment of air bubbles, resulting in poor insulation and moisture resistance. There are problems such as deterioration of properties.

[0003] In the field of semiconductors, as a method of mounting components on a printed circuit board, a shift from a conventional mounting method to a surface mounting method is progressing. In the surface mounting method, the entire package is heated to the solder temperature, and a package crack due to thermal shock has become a serious problem. Furthermore, in recent years, higher integration of semiconductor devices,
The increase in element size and the miniaturization of wiring width are rapidly progressing, and the problem of package cracking is becoming more serious. As methods for preventing package cracks, there are methods such as toughening of the resin structure, high strength by high loading of silica, and low water absorption. In order to overcome the above problems, an epoxy resin having excellent toughness and low viscosity has been desired.

[0004] As the low-viscosity epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin and the like are generally and widely used. Among these epoxy resins, those having low viscosity are liquid at room temperature, and depending on the application, Difficult to handle. Furthermore, these epoxy resins are not sufficient in heat resistance, mechanical strength, and toughness.

Further, Japanese Patent Publication No. 4-7365 proposes an epoxy resin composition for semiconductor encapsulation using a biphenyl-based epoxy resin as a main component as one having improved handling workability, heat resistance, toughness and the like. However, there is a disadvantage that the curing speed is slow.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide excellent moldability such as rapid curability and fluidity, and
It is an object of the present invention to provide an epoxy resin composition for encapsulating electronic components such as semiconductor elements, which gives a cured product having excellent mechanical strength, heat resistance, crack resistance and the like.

[0007]

That is, the present invention relates to an epoxy resin composition comprising an epoxy resin and a curing agent, wherein the epoxy resin component has the following general formula (1):

Embedded image An epoxy resin composition for encapsulating electronic parts, characterized by containing an epoxy resin represented by the formula:

The epoxy resin represented by the above general formula (1) is prepared by the following general formula (2)

Embedded image The compound is produced by reacting a 4,4'-dihydroxydiphenyl ether compound represented by the following formula with epichlorohydrin. This reaction can be performed in the same manner as a usual epoxidation reaction.

For example, after dissolving 4,4'-dihydroxydiphenyl ether in excess epichlorohydrin,
In the presence of an alkali metal hydroxide such as sodium hydroxide, potassium hydroxide or the like, 50 to 150 ° C, preferably 60 to 1 ° C.
A method of reacting at 20 ° C. for 1 to 10 hours is exemplified. The amount of epichlorohydrin used at this time was
0.8-2 mol, preferably 0.9-1.
It is in the range of 2 moles. After completion of the reaction, excess epichlorohydrin is distilled off, and the residue is dissolved in a solvent such as toluene or methyl isobutyl ketone, filtered, washed with water to remove an inorganic circle, and then the solvent is distilled off to obtain the desired epoxy compound. A resin can be obtained.

In the general formula (1), n is an integer of 0 or more. The value of n can be easily adjusted by changing the molar ratio of epichlorohydrin to the 4,4′-dihydroxydiphenyl ether compound used during the synthesis reaction of the epoxy resin.
Preferably, it is contained at 0% or more. If n is less than 50%, a low-viscosity epoxy resin cannot be obtained. Further, the substituents R _{1 to} R ₈ are a hydrogen atom, a halogen atom or
Show 6 hydrocarbon group, preferably R ₁ to R ₈ is a hydrogen atom 4,4'-dihydroxydiphenyl ether is used.

As the curing agent used in the resin composition of the present invention, those generally known as curing agents for epoxy resins can be used, but those having a phenolic hydroxyl group are preferably used. For example, divalent phenols such as bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4′-biphenol, 2,2′-biphenol, hydroquinone, resorcinol, and naphthalene diol, or tris- (4-hydroxyphenyl) Ethane, phenol novolak, o-
Trivalent or higher phenols represented by cresol novolak, naphthol novolak, polyvinyl phenol, etc., and further phenols, naphthols or bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4′-biphenol, 2,
There are polyhydric phenolic compounds synthesized by condensing agents such as formaldehyde, acetaldehyde, benzaldehyde, p-hydroxybenzaldehyde and p-xylylene glycol of dihydric phenols such as 2'-biphenol, hydroquinone, resorcinol and naphthalene diol. . In addition, especially for sealing applications requiring transparency, phthalic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylhymic anhydride, nadic anhydride And acid anhydrides such as trimellitic anhydride are preferably used. In some cases, amines may be used. In the resin composition of the present invention, one or more of these curing agents may be used in combination.

In addition to the 4,4'-diphenyl ether-based epoxy resin used as an essential component of the present invention, a usual epoxy resin having two or more epoxy groups in a molecule is used in combination with the resin composition of the present invention. May be. Examples include bisphenol A, bisphenol F, bisphenol S, fluorene bisphenol, 4,4'-biphenol, 2,2'-biphenol, hydroquinone,
Dihydric phenols such as resorcinol and naphthalene diol, or tris- (4-hydroxyphenyl) methane, 1,1,2,2-tetrakis- (4-hydroxyphenyl) ethane, phenol novolak, o-cresol novolak, etc. There are glycidyl ether compounds derived from trivalent or higher phenols or halogenated bisphenols such as tetrabromobisphenol A. These epoxy resins can be used singly or in combination of two or more. The compounding amount of the epoxy resin represented by the general formula (1) is 5 to 100% of the entire epoxy resin.
Range.

A conventionally known curing accelerator can be used in the resin composition of the present invention, if necessary. For example, there are amines, imidazoles, organic phosphines, Lewis acids and the like. The amount of addition is usually 100
It is in the range of 0.2 to 5 parts by weight with respect to parts by weight.

A filler can be used in the resin composition of the present invention, if necessary. As the filler, for example, spherical or crushed fused silica, silica powder such as crystalline silica, alumina powder, glass powder and the like are used.

If necessary, the resin composition of the present invention may contain a release agent such as carnauba wax or OP wax, γ
-Coupling agents such as glycoxypropyltrimethoxysilane, coloring agents such as carbon black, flame retardants such as antimony trioxide, low stress agents such as silicone oil, lubricants such as calcium stearate, and the like can be used.

[0016]

The present invention will be described in more detail with reference to the following examples.

REFERENCE EXAMPLE 1 101 g of 4,4'-dihydroxydiphenyl ether was dissolved in 462.5 g of epichlorohydrin, and 0.3 g of benzyltriethylammonium chloride was further added. 0.3 g was added dropwise over 3 hours. During this time, the generated water was removed from the system by azeotropic distillation with epichlorohydrin, and the distilled epichlorohydrin was returned to the system. After the completion of the dropwise addition, the reaction was further continued for one hour. Thereafter, the salt generated by filtration was removed, and after washing with water, epichlorohydrin was distilled off to obtain 146.2 g of a pale yellow crystalline epoxy resin. The epoxy equivalent is 169,
Melting point was 86 ° C. The melt viscosity at 150 ° C. was 0.2 poise. Table 1 shows the MNR measurement results of the obtained resin.

[Table 1]

Example 1 The epoxy resin (epoxy resin A) obtained in Reference Example 1 as an epoxy resin component, a phenol novolak hardener having a softening point of 100 ° C., a spherical fused silica powder having an average particle diameter of 21 μm, and an epoxy resin having an average particle diameter of 6 μm Table 2 shows the crushed fused silica powder, hardening accelerator (triphenylphosphine) and other additives.
After mixing at the ratio shown in the following, using a mixing roll,
The mixture was kneaded at 110 ° C. for 4 minutes, cooled and pulverized to prepare a sealing resin composition. A test piece was prepared using this sealing resin composition, and the bending strength and the bending elastic modulus were measured. Furthermore, 84 pin IC is molded, and after the post cure, 85 ° C.
After moisture absorption was performed for 24 hours, 48 hours, and 72 hours in an 85% constant temperature and humidity machine, the package was immersed in a 260 ° C. solder bath for 10 seconds, and cracks of the package were observed. Table 2 shows the results.

Example 2 Epoxy resin (epoxy resin A) obtained in Reference Example 1 and a cresol novolak type epoxy resin (YDCN-700, manufactured by Toto Kasei Co., Ltd.) as an epoxy resin component, a phenol novolak curing agent having a softening point of 100 ° C. , Average particle size 21
μm spherical fused silica powder, crushed fused silica powder having an average particle size of 6 μm, a curing accelerator (triphenylphosphine), and other additives were mixed at the ratios shown in Table 2, and then mixed in the same manner as in Example 1. Physical properties were measured. Table 2 shows the results.

Comparative Example 1 Cresol novolak type epoxy resin (YDCN-700, manufactured by Toto Kasei Co., Ltd., softening point 71) as an epoxy resin component
° C) to obtain a sealing resin composition in the same manner as in Example 1, and then measured the physical properties in the same manner as in Example 1. Table 2 shows the results.

[0020]

The epoxy resin composition obtained according to the present invention has an extremely low viscosity in a molten state, so that it is easy to handle, and the obtained molded product exhibits excellent cured physical properties. It is suitable for use in the field of sealing electronic components, and has an excellent effect of improving crack resistance.

[Table 2]

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Makoto Yamagata 3-2 5D3 Kiyomidai, Kisarazu-shi, Chiba (56) References JP-A-5-217702 (JP, A) JP-A-60-110747 (JP, A) (JP) B-72 (JP, B2) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01C 1/00-1/16 H01L 23/28-23/30

Claims (1)

(57) [Claims] An epoxy resin composition comprising an epoxy resin and a curing agent, wherein the epoxy resin component has the following general formula (1): An epoxy resin composition for sealing electronic components, comprising an epoxy resin represented by the formula: