JPS6185432A - Epoxy resin molding material for encapsulation of semiconductor device - Google Patents

Abstract

PURPOSE:To obtain the titled material having excellent thermal shock resistance, high reliability of the glass transition temperature and moisture-resistance, etc., and excellent moldability, by compounding an epoxy resin with a rubber- shaped filler having specific diameter and a spherical filler at specific ratios. CONSTITUTION:The objective molding material can be produced by compounding (A) an epoxy resin (preferably an o-cresol novolac epoxy resin having an epoxy equivalent of 180-205) with (B) a rubber-shaped filler wherein the content of granules having diameter of 44-149mu is 1-6wt%, and (C) a spherical filler and adding other components to the mixture. The amount of the granules having diameter of 44-149mu in the component B+C is adjusted to 8-40%, preferably 10-30%. The filler is preferably silica.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an epoxy resin molding material for encapsulating semiconductor devices (hereinafter referred to as encapsulating material) having excellent thermal shock resistance.

[Conventional technology]

Resin encapsulation of semiconductor devices by transfer molding using a encapsulating material is the mainstream of initial pressure methods due to its high productivity. Furthermore, as the reliability of sealing materials improves, the range of application has expanded to include VLSI devices such as memories and microcomputers, and further improvements in reliability are required.

Particularly in recent years, as device sizes have become larger to improve the degree of integration and packages have become thinner and smaller, crack resistance of sealing materials in thermal cycle tests has become required.

Conventionally, in response to these demands, methods of reducing the coefficient of thermal expansion of the sealing material and methods of lowering the modulus of elasticity to provide flexibility have been studied. However, increasing the amount of filler to lower the coefficient of thermal expansion results in loss of flexibility and fluidity, resulting in f
In order to improve usability, lowering the degree of crosslinking resulted in a decrease in the glass transition source by 1 degree, which impairs high-temperature properties, and also reduces moisture resistance, so none of the methods were satisfactory.

[Problems to be solved by Ev 1] The invention is to develop a useful sealing material that has excellent thermal shock resistance, reliability in terms of glass transition temperature and moisture resistance, and excellent molding workability. This is what we are trying to provide.

[Means for solving problems]

The present invention provides an epoxy resin with (a) a particle size of 44 to 149 μm;
consisting of a crushed stone filler whose content of particles is 1 to 6 M-W% and (b) a spherical filler, and whose content of particles with a particle size of 44 μ to 149 μ in (ml + (bl) is 8 to 40 wt. The invention relates to an epoxy resin molding material for semiconductor encapsulation, which is characterized by the fact that it contains a filling layer of %.

That is, it was discovered that a crushed stone-like filler or a spherical filler with a small particle size greatly improves the thermal shock resistance of a sealing material by -1, which led to the present invention. Here, as the crushed stone-like filler with a small particle size, it is necessary to use one with a particle content of 44μ to 149μ in the range of 1 to 6% by weight. If the content of particles is less than 1% by weight, the fluidity will be significantly reduced. Also, of the total amount of crushed stone filler and spherical filler, 4
8 to 40% by weight of particles of 4 to 149μ
0-50X: It is necessary to adjust to J1%. 8% by weight
If it is less than 40% by weight, the amount of burrs in a thick gap of about 50 μm in the mold increases, and if it exceeds 40% by weight, the amount of burr in a thin gap of about 10 μm increases, seriously impairing molding workability. Note that the spherical filler in the present invention does not necessarily have to be a perfect sphere, but refers to a filler that does not have an angular shape. Further, in the present invention, the particle size is measured using a standard sieve according to JIS standards. Furthermore, as a filler used in the present invention.

Fused silica, crystalline silica, glass, alumina.

Although zircon and the like are rejected, silica is preferred because it has excellent properties such as moisture resistance as well as heat crack resistance.

Epoxy resins that can be used in the present invention include, for example, glycidyl ethers of phenols such as bisphenol A, bisphenol F, resorcinol, phenol novolac, and cresol novolak; glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol nat .

Glycidyl esters of carboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, and tetrahydrophthalic acid, glycidyl-type epoxy resins such as those in which the active hydrogen bonded to the nitrogen atom of aniline and isotheateric acid is replaced with a glycidyl group, and intramolecular Examples include so-called alicyclic epoxides obtained by epoxidizing the olefin bonds of Among them, θ- with an epoxy equivalent of 180 to 205
It is a cresol novolak type eboki.

There are no particular restrictions on the curing agent, but phenolic resins such as novolak-type phenolic resins and novolak-type cresol resins, acid anhydrides such as tetrahydrophthalic anhydride and pyromellitic anhydride, diaminodiphenylmethane,
Amines such as diaminodiphenylsulfur, adipic acid dihydrazide, isophthalic acid dihydrazide, etc.
Basic acid dihydrazides and the like can be used.

Furthermore, as a curing accelerator, for example, imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole, ternary amines such as benzyldimethylamine, and organic phosphorus compounds such as tributylphosphine and triphenylphosphine can be used. Preferably, other colorants, mold release agents, flame retardants, coupling agents, etc. may be used as necessary.

As a method for producing the epoxy resin molding material for encapsulating semiconductor devices of the present invention, a melt mixing method using a mixing roll or an extruder is suitable, and a composition with desired fluidity can be produced by these methods. .

〔Example〕 This will be specifically explained below using examples.

Examples 1 to 5 and Comparative Examples 1 to 3 Fillers shown in Table 1, softening point 82°C, epoxy half amount 198
a θ-cresol novolac type epoxy resin (1), and a brominated bisphenol type epoxy resin (2) having a softening point of 76°C and an epoxy equivalent fi4QO.

The additives shown in Table 2 were mixed with the ingredients shown in Table 2, and 80
Melt mixing was performed for 5 minutes on a mixing roll at °C. The melt-mixed material was taken out in the form of a sheet, cooled, and then crushed and used for molding.

Table 1 Particle size of filler (%) Table 2 Examples The measurement methods and test methods for the properties shown in Table 2 are as follows:
I will clarify. Thermal shock resistance was tested by using a flat package and checking by cranking the resin part along the chip. Thermal shock conditions were 7 cycles of 150°C heating bath for 1 minute and 21 minutes of liquid N, and the number of times that half of the packages were cranked was defined as 'l'+shock resistance.

The Paris length was measured using a Venus with a slit of the indicated thickness at a mold temperature of 180°C and a molding pressure cuff of 0 kg/-. The glass transition temperature was determined from the transition point of the thermal expansion curve. The volume resistivity was measured according to JIS K6911, and the pressure pressure treatment (PCT) was carried out in 2 atmospheres of water vapor for DDQ.

Spiral flow follows EMMI-Summer-661C Ml+
However, A of 50 to 40 inches is appropriate.

Comparative Example 1 is a standard material made conventionally and has rX resistance.
S is a material with no particular drawbacks in terms of its poor impact resistance. In addition, in Comparative Example 2, where the filler was made finer, the amount of burr increased with a thickness of 50 mm.
0 μ thick Paris 5″ is increased. On the other hand, in Example 1
In the examples according to the present invention shown in 5 to 5, the IH thermal shock resistance is significantly improved, and furthermore, the glass transition temperature, moisture resistance, etc. are excellent (in addition, there is little occurrence of paris), and the moldability is also good. (・I understand.

〔Effect of the invention〕

According to the present invention, a sealant which has excellent thermal shock resistance and is improved by 8i in terms of reliability such as glass transition temperature and moisture resistance, and molding workability has been obtained.

Claims (1)

[Claims] 1. In the epoxy resin, (a) a crushed stone-like filler containing 1 to 6% by weight of particles with a particle size of 44 to 149 μ; and (b)
An epoxy for encapsulating semiconductor devices, which is made of a spherical filler and contains 8 to 40% by weight of particles with a particle diameter of 44 to 149 μ out of (a) + (b). Resin molding material. 2. The epoxy resin molding material for encapsulating a semiconductor device according to claim 1, wherein the epoxy resin is a low cresol novolac type epoxy resin having an epoxy equivalent of 180 to 205. 3. The epoxy resin molding material for encapsulating a semiconductor device according to claim 2, wherein the filler is silica.