JPH07138348A - Epoxy resin composition and sealed semiconductor device - Google Patents

Abstract

PURPOSE:To obtain a long-reliable epoxy resin compsn. excellent in moisture resistance and molbaility. CONSTITUTION:This epoxy resin compsn. contains as the essential ingredients an epoxy resin, a phenol resin of the formula (wherein R<1> is H or an alkyl; and (n) is an integer of 0 of higher), and an inorg. filler in an amt. of 25-92wt.% based on the compsn. The compsn. is used for sealing a semiconductor chip to give the objective sealed semiconductor device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition having excellent moisture resistance and molding workability, and a semiconductor encapsulation device.

[0002]

2. Description of the Related Art In recent years, in the field of semiconductor integrated circuits,
At the same time as technology development for high integration and high reliability, automation of the mounting process of semiconductor devices is being promoted. For example, when mounting a flat package type semiconductor device on a circuit board, conventionally, soldering is performed for each lead pin, but recently, a solder dipping method or a solder reflow method has been adopted.

[0003]

A semiconductor device encapsulated with a conventional epoxy resin such as a novolac type epoxy resin, a dicyclopentadiene type phenol resin, and a resin composition comprising silica powder has excellent moisture resistance,
There is a drawback that the strength is remarkably reduced under high temperature conditions such as heat molding. In particular, since the strength of the semiconductor encapsulation device immediately after molding is poor, there is a drawback that workability during molding is significantly reduced.

The present invention has been made in order to solve the above-mentioned drawbacks, and by improving the strength of a resin composition under high temperature conditions while maintaining excellent moisture resistance, molding workability is excellent and at the same time. The present invention aims to provide an epoxy resin composition and a semiconductor encapsulation device capable of guaranteeing long-term reliability.

[0005]

Means for Solving the Problems As a result of intensive studies aimed at achieving the above object, the present inventors have found that a resin composition excellent in moisture resistance and molding workability can be obtained by using a specific phenol resin. The present invention has been completed and the present invention has been completed.

That is, the present invention includes (A) an epoxy resin, (B) a phenol resin represented by the following general formula, and

[0007]

[Chemical 3] (In the formula, R ¹ is a hydrogen atom or an alkyl group, and n is 0
Or an integer of 1 or more) (C) An inorganic filler is an essential component, and the above (C) is used for the entire resin composition.
An epoxy resin composition comprising the inorganic filler of 25 to 90% by weight. A semiconductor encapsulation device is obtained by encapsulating a semiconductor chip with a cured product of this epoxy resin composition.

The present invention will be described in detail below.

The epoxy resin (A) used in the present invention can be used without particular limitation in its molecular weight and the like as long as it is used for sealing. As a specific compound, for example,

[0010]

[Chemical 4] (However, in the formula, n represents 0 or an integer of 1 or more),

[0011]

[Chemical 5] (Wherein n represents 0 or an integer of 1 or more) and the like, and these can be used alone or in combination.

As the (B) phenol resin used in the present invention, those obtained by the reaction of cyclohexanedione and phenols and represented by the above general formula are used. As a specific compound, for example,

[0013]

[Chemical 6] (However, in the formula, n represents 0 or an integer of 1 or more),

[0014]

[Chemical 7] (Wherein n represents 0 or an integer of 1 or more) and the like, and these can be used alone or in combination. In addition to this phenol resin, a novolac type phenol resin obtained by reacting phenols such as phenol and alkylphenol with formaldehyde or paraformaldehyde, and modified resins thereof can be used in combination.

As the inorganic filler (C) used in the present invention, generally used ones are widely used. Among them, silica powder having a low impurity concentration and an average particle diameter of 30 μm or less is preferably used. . If the average particle size exceeds 30 μm, the moisture resistance and the moldability are deteriorated, which is not preferable. The blending ratio of the inorganic filler is 25 to 90 with respect to the entire resin composition.
It is preferable to mix them so as to contain them by weight. When the proportion is less than 25% by weight, the hygroscopicity of the resin composition is high and the moisture resistance after solder immersion is poor, and when it exceeds 90% by weight, the fluidity is extremely deteriorated and the moldability is poor, which is not preferable.

The epoxy resin composition of the present invention contains an epoxy resin, a specific phenol resin and an inorganic filler as essential components, but within a range not deviating from the object of the present invention.
Further, if necessary, for example, natural waxes, synthetic waxes, metal salts of linear fatty acids, acid amides, esters, release agents such as paraffin, flame retardants such as antimony trioxide, colorants such as carbon black, A silane coupling agent, various curing accelerators, rubber-based or silicone-based low stress imparting agents, and the like can be appropriately added and blended.

A general method for preparing the epoxy resin composition of the present invention as a molding material is to mix the above-mentioned epoxy resin, a specific phenol resin, an inorganic filler and other components, and homogenize them sufficiently with a mixer or the like. It is possible to mix and perform melt mixing treatment with a hot roll or mixing treatment with a kneader or the like, then cool and solidify and pulverize to an appropriate size to obtain a molding material. If the molding material thus obtained is applied to sealing, coating, insulation, etc. of electronic parts or electric parts such as semiconductor devices, excellent properties and reliability can be imparted.

The semiconductor encapsulation device of the present invention can be easily manufactured by encapsulating a semiconductor chip using the above molding material. The semiconductor chip to be sealed is not particularly limited to, for example, an integrated circuit, a large scale integrated circuit, a transistor, a thyristor, a diode and the like. The most common method of sealing is a low-pressure transfer molding method, but sealing by injection molding, compression molding, casting or the like is also possible. After sealing with a molding material, it is heated and cured, and finally a semiconductor sealing device sealed with this cured product is obtained. The curing by heating is preferably performed by heating to 150 ° C.

[0019]

The epoxy resin composition and the semiconductor encapsulation device of the present invention are prepared by using a specific phenol resin.
The water absorption of the resin composition was reduced, the thermomechanical properties and the low stress properties were improved, the deterioration in moisture resistance was reduced, and the molding workability was excellent.

[0020]

EXAMPLES Next, the present invention will be described with reference to examples, but the present invention is not limited to these examples. In the following examples and comparative examples, “%” means “% by weight”.

Example 1 10% of the above-mentioned epoxy resin of Chemical formula 4, 7.5% of the above-mentioned phenolic resin of Chemical formula 6, 81% of silica powder, 0.2% of curing accelerator
%, Ester waxes 0.3% and silane coupling agent 1.0% were mixed at room temperature, further kneaded at 90 to 95 ° C., cooled, and then pulverized to produce a molding material (A).

Example 2 10% of the epoxy resin of Chemical formula 4 used in Example 1, 3.5% of the phenolic resin of Chemical formula 6 used in Example 1, 4.0% of novolac type phenolic resin, 81% of silica powder, and 0.2% of curing accelerator.
%, Ester waxes 0.3% and silane coupling agent 1.0% were mixed at room temperature, further kneaded at 90 to 95 ° C., cooled, and then pulverized to produce a molding material (B).

Comparative Example 1 10% of the epoxy resin of Chemical formula 4 used in Example 1, 7.5% of a phenol resin represented by the following formula,

[0024]

[Chemical 8] 81% of silica powder, 0.2% of hardening accelerator, 0.3% of ester waxes and 1.0% of silane coupling agent are mixed at room temperature, further kneaded at 90 to 95 ° C, cooled, and then ground to obtain a molding material (C). Manufactured.

Comparative Example 2 10% of the epoxy resin of Chemical formula 4 used in Example 1, 5.5% of the phenolic resin of Chemical formula 8 used in Comparative Example 1, 2% of novolac type phenolic resin, 81% of silica powder, 0.2% curing accelerator %,
0.3% ester wax and silane coupling agent
1.0% was mixed at room temperature, further kneaded at 90 to 95 ° C., cooled, and then pulverized to produce a molding material (D).

Molding materials (A) to (D) thus produced
Was used to transfer transfer into a mold heated to 170 ° C., and the semiconductor chip was sealed and cured to manufacture a semiconductor sealing device. Various tests were conducted on these semiconductor encapsulation devices, and the results are shown in Table 1. The epoxy resin composition and the semiconductor encapsulation device of the present invention are excellent in moisture resistance and solder heat resistance. The remarkable effect of the invention could be confirmed.

[0027]

[Table 1] * 1: Diameter 50 mm, thickness 3 mm by transfer molding
The molded product of No. 1 was prepared, and it was left in saturated steam at 127 ° C. and 2.5 atm for 24 hours and measured by the increased weight. * 2: Make a molded product similar to the case of water absorption, 175 ℃, 8
After post-curing for a certain time, a test piece of an appropriate size was prepared and measured using a thermomechanical analyzer. * 3: Tested according to JIS-K-6911.

[0028]

As is clear from the above description and Table 1, the epoxy resin composition and the semiconductor encapsulating device of the present invention are excellent in moisture resistance and molding workability and can guarantee reliability for a long period of time. it can.

Claims (2)

[Claims] 1. An epoxy resin (A), a phenolic resin represented by the following general formula (B), and (In the formula, R ¹ is a hydrogen atom or an alkyl group, and n is 0
Or an integer of 1 or more) (C) An inorganic filler is an essential component, and the above (C) is used for the entire resin composition.
An epoxy resin composition, characterized by containing the inorganic filler according to the above in a proportion of 25 to 90% by weight. 2. An epoxy resin (A), a phenol resin represented by the following general formula (B), and (In the formula, R ¹ is a hydrogen atom or an alkyl group, and n is 0
Or an integer of 1 or more) (C) An inorganic filler is an essential component, and the above (C) is used for the entire resin composition.
A semiconductor encapsulation device, wherein a semiconductor chip is encapsulated with a cured product of an epoxy resin composition containing the inorganic filler in a proportion of 25 to 90% by weight.