JP2000191749A - Epoxy resin composition and device for sealing semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition capable of being highly charged without deteriorating flowability, giving improved interfacial strengths between organic components and inorganic components, and excellent in moisture resistance, or the like, by compounding an epoxy compound, a phenolic compound, a specific titanate- based coupling agent, alumina powder and a curing accelerator. SOLUTION: This epoxy resin composition comprises (A) a solid epoxy compound having two or more epoxy groups in the molecule, (B) a solid phenolic compound having two or more phenolic hydroxyl groups in the molecule, (C) a titanate-based coupling agent of the formula [R1, R2 are each an alkyl; (x), (y) are each an integer of >=1, provided that (x)+(y) = 4] (D) alumina powder having the maximum particle diameter of <100 μm and an average particle diameter of <=60 μm, and (E) a curing accelerator as essential components. Therein, the component D is contained in an amount of 25-90 wt.% based on the total amount of the resin composition. In the epoxy resin composition, the components C and E are preferably contained in amounts of 0.01-5 wt.% and 0.01-5 wt.%, respectively, based on the total amount of the resin composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to moisture resistance, heat resistance,
Moldability, especially excellent filling property of thin part, excellent abrasion resistance of mold, good thermal conductivity, good heat dissipation, excellent mechanical properties, highly reliable epoxy resin composition with balanced properties and The present invention relates to a semiconductor sealing device.

[0002]

2. Description of the Related Art Conventionally, a method of sealing electronic components such as diodes, transistors, and integrated circuits with a thermosetting resin has been used. This resin sealing is economically advantageous as compared with the hermetic sealing method using glass, metal, and ceramic, and is therefore widely used. As a sealing resin, epoxy resin is most commonly used among thermosetting resins in terms of reliability and price. For the epoxy resin, a curing agent such as an acid anhydride, an aromatic amine, and a novolak phenol resin is used. Among these, the epoxy resin using the novolac phenol resin as a curing agent uses other curing agents. Moldability,
Because of its excellent reliability, low toxicity and low cost, it is widely used as a resin for semiconductor encapsulation. As the filler, generally, fused silica powder or crystalline silica powder is used together with the above-mentioned curing agent. In recent years, with the surface mounting of semiconductor parts and further increase in power,
There has been a demand for the development of a semiconductor sealing resin having good heat dissipation and solder heat resistance.

However, a resin composition comprising an epoxy resin using a novolak type phenolic resin as a curing agent and a fused silica powder has a small coefficient of thermal expansion, good moisture resistance, and an open bond wire by a warm-cold cycle test. Although it has the advantage of being excellent in resin cracks, pellet cracks, and the like, it has a drawback that power semiconductors have poor heat dissipation due to low thermal conductivity and thus cannot perform their functions in power semiconductors with large power consumption.

On the other hand, a resin composition comprising an epoxy resin using a novolak type phenol resin as a curing agent and crystalline silica powder has an increased thermal conductivity and increased heat dissipation when the proportion of the crystalline silica powder is increased. Although good, the thermal expansion coefficient is large, and there is a drawback that the reliability with respect to moisture resistance is deteriorated. Furthermore, the sealed product obtained from this resin composition has the disadvantages that the mechanical properties are deteriorated and that the mold is greatly worn during molding. Therefore, there is naturally a limit in increasing the thermal conductivity of the sealing resin composition using the crystalline silica powder.

A resin composition comprising an epoxy resin using a novolak-type phenol resin as a curing agent and silicon nitride powder has a characteristic of high thermal conductivity and good heat dissipation, but uses silica powder. As compared with the material, there is a major demerit in that the mechanical properties are deteriorated and the mold is extremely worn during molding.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks, and does not impair the fluidity.
High filling, improved interfacial strength of organic and inorganic components, excellent moisture resistance, solder heat resistance, moldability, especially excellent filling of thin-walled parts, abrasion resistance of molds, thermal conductivity and heat dissipation An object of the present invention is to provide a highly reliable epoxy resin composition and a semiconductor encapsulation device that are well-balanced in characteristics and excellent in mechanical characteristics.

[0007]

Means for Solving the Problems The present inventor has conducted intensive studies in an attempt to solve the above-mentioned problems, and as a result, by using a specific titanate coupling agent, an organic component such as a resin and alumina powder have been obtained. Maximum particle size of 100 treated with a specific coupling agent that enhances reactivity with both inorganic components
It has been found that the use of alumina powder having an average particle size of 60 μm or less solves the above-mentioned problems and achieves the object, thereby completing the present invention.

That is, the present invention provides (A) a solid epoxy compound having two or more epoxy groups in one molecule, (B) a solid phenolic compound having two or more phenolic hydroxyl groups in one molecule, C) a titanate-based coupling agent represented by the following general formula:

[0009]

Embedded image (Wherein, R ¹ and R ² represent an alkyl group, and x and y
Is an integer of 1 or more and satisfies x + y = 4. (D) Alumina powder having a maximum particle size of 100 μm or less and an average particle size of 60 μm or less and (E) a curing accelerator are essential components, and the alumina powder of (D) is 25 to 90 wt. % Of the epoxy resin composition. Further, there is provided a semiconductor sealing device wherein a semiconductor chip is sealed with a cured product of the epoxy resin composition.

Hereinafter, the present invention will be described in detail.

The epoxy compound (A) used in the present invention comprises:
What is necessary is just a solid thing which has two or more epoxy groups in one molecule. As this solid epoxy compound, bisphenol type epoxy resin, novolak type epoxy resin,
Examples include a triphenylmethane-based epoxy resin, a dicyclopentadiene-type epoxy resin, and a phenol-based multifunctional epoxy resin. Of these, a novolak-type epoxy resin obtained by epoxidizing the hydroxyl group of a phenol novolak resin and a phenol-based multifunctional epoxy resin are preferable. It is.

The phenolic compound (B) used in the present invention may be a solid compound having two or more phenolic hydroxyl groups in one molecule. As the solid organic compound, a phenol novolak resin is preferable.

As the titanate-based coupling agent (C) used in the present invention, those represented by the aforementioned general formula (3) are used. Specifically, for example,

[0014]

Embedded image And titanate surface treatment agent Titacoat series C-1
51 (manufactured by Nippon Soda Co., Ltd.), and these can be used alone or in combination of two or more. Further, it can be used in combination with a known silane coupling agent. The mixing ratio of the titanate-based coupling agent is 0.01 to 5% by weight based on the entire resin composition.
It is desirable to mix them so as to contain them. The ratio is
If it is less than 0.01% by weight, the interface strength between the organic and inorganic components cannot be improved, and if it exceeds 5% by weight, the curability and moldability are extremely poor, which is not preferable.

(D) Maximum particle size 100 μm used in the present invention
Below, as an alumina powder having an average particle size of 60 μm or less,
A material having a low impurity concentration is used. Average particle size 60μm
If it exceeds 300, the moisture resistance and the moldability will be poor, which is not preferable. The mixing ratio of the alumina powder is 2 to the entire resin composition.
It is preferable to mix them in an amount of 5 to 90% by weight. When the proportion is less than 25% by weight, the resin composition has high hygroscopicity, is inferior in moisture resistance after solder immersion, and has a proportion of 90% by weight.
If it exceeds, the fluidity becomes extremely poor and the moldability is poor, which is not preferable.

As the (E) curing accelerator used in the present invention, a curing reaction between the epoxy group of the epoxy compound (A) (novolak type epoxy resin) and the hydroxyl group of the phenolic compound (phenol novolak resin) (B) is used. Any type can be used as long as it promotes the use of phosphorus-based curing accelerators, imidazole-based curing accelerators, DBU-based curing accelerators, and other curing accelerators. These can be used alone or in combination of two or more. Can be used. Especially softening point 100
An amine compound, an imidazole compound, or a phosphorus compound having a temperature of not less than ° C is suitable.

Specifically, for example, 2- (dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, benzyldimethylamine,
Amines such as alphamethylbenzyldimethylamine and 1,8-diazabicycloundecene; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-heptadecylimidazole and 2-ethyl-4-methylimidazole; Phenylphosphine, tricyclohexylphosphine, tributylphosphine, methyldiphenylphosphine, dibutylphenylphosphine,
Diphenylbutylphosphine, tris (paramethoxyphenyl) phosphine, tri (methatyl) phosphine,
And phosphorus compounds such as trinaphthylphosphine and tris (2,6-dimethoxyphenyl) phosphine.
Further, it is preferable that these hardening accelerators are previously heated and kneaded with a lubricant having a softening point of 100 ° C. or higher, and then pulverized to be used as a surface coating type solid hardening accelerator.

It is desirable that the curing accelerator be blended so as to contain 0.01 to 5% by weight based on the whole resin composition. If the proportion is less than 0.01% by weight,
The gel time of the resin composition is long and the curing properties are poor,
On the other hand, if it exceeds 5% by weight, the fluidity becomes extremely poor and the moldability is inferior, the electrical properties also deteriorate, and the moisture resistance is inferior.

The epoxy resin composition of the present invention comprises the above-mentioned epoxy resin, phenolic resin, a specific titanate-based silane coupling agent, alumina powder having a maximum particle size of 100 μm or less and an average particle size of 60 μm or less, and a curing accelerator as essential components. However, to the extent not contrary to the object of the present invention,
If necessary, for example, natural waxes, synthetic waxes, metal salts of straight-chain fatty acids, acid amides, esters,
Release agents such as paraffin, flame retardants such as antimony trioxide,
A coloring agent such as carbon black and a low-stress imparting agent such as rubber and silicone can be appropriately added and blended.

A general method for preparing the epoxy resin composition of the present invention as a molding material is as follows: the epoxy resin, the phenol resin, the specific titanate-based silane coupling agent, the maximum particle diameter of 100 μm or less, and the average particle diameter of 60 μm.
The following alumina powder, a hardening accelerator and other components are blended, mixed sufficiently uniformly by a mixer or the like, and further subjected to a melt-mixing process using a hot roll or a mixing process using a kneader or the like, and then cooled and solidified to obtain an appropriate size. It can be pulverized into a molding material. If the molding material thus obtained is applied to sealing, coating, insulating, etc. of electronic parts or electric parts such as semiconductor devices, excellent properties and reliability can be imparted.

Further, the semiconductor device of the present invention can be easily manufactured by sealing a semiconductor chip using the above-mentioned 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 sealing method 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, the mixture is heated and cured, and finally a semiconductor device sealed with the cured product is obtained. Curing by heating is desirably performed by heating to 150 ° C. or higher.

[0022]

The epoxy resin composition and the semiconductor encapsulation device of the present invention strengthen the resin interface by using a specific titanate-based silane coupling agent with respect to the above-described epoxy resin, phenol resin, and specific alumina powder. As a result, the mechanical properties are improved, and the moisture resistance, heat resistance, moldability, especially the filling properties of thin-walled parts, the abrasion resistance of the mold are excellent, the thermal conductivity and heat dissipation are good, and their properties are balanced. It is reliable and reliable.

[0023]

Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples. Hereinafter, “%” means “% by weight” in Examples and Comparative Examples.

Example 1 85.0% of alumina powder having a maximum particle size of 100 μm or less was placed in a Henschel mixer, and stirred with stirring. 151 (manufactured by Nippon Soda Co., Ltd., trade name) was added to perform surface treatment of the above alumina powder. Next, 7.6% of novolak type epoxy resin (epoxy equivalent: 200), 3.8% of phenol novolak resin (hydroxyl equivalent: 104), 0.5% of triphenylphosphine, 0.4% of carnauba wax, and 0.4% of carbon black. 3% and antimony trioxide 2.0%
Was mixed at room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a molding material.

Example 2 85.0% of alumina powder having a maximum particle size of 100 μm or less was placed in a Henschel mixer, and stirred with stirring. 151 (manufactured by Nippon Soda Co., Ltd., trade name) was added to perform surface treatment of the above alumina powder. Next, 7.6% of a phenolic polyfunctional epoxy resin (epoxy equivalent: 215), 3.8% of a phenol novolak resin (hydroxyl equivalent: 104), 0.5% of triphenylphosphine, 0.4% of carnauba wax,
1. 0.3% carbon black and antimony trioxide
0% was mixed at room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a molding material.

Example 3 85.0% of alumina powder having a maximum particle size of 100 μm or less was put into a Henschel mixer, and stirred while stirring. 151 (manufactured by Nippon Soda Co., Ltd., trade name) was added to perform surface treatment of the above alumina powder. Next, 7.6% of a phenolic polyfunctional epoxy resin (epoxy equivalent 170), 3.8% of a polyfunctional novolak resin (hydroxyl equivalent 97), 0.5% of triphenylphosphine, 0.4% of carnauba wax, carbon 0.3% of black and 2.0% of antimony trioxide were mixed at room temperature, kneaded and cooled at 90 to 110 ° C, and then pulverized to produce a molding material.

COMPARATIVE EXAMPLE 1 85.0% of alumina powder having a maximum particle size of 100 μm or less was placed in a Henschel mixer, and 0.4% of an epoxysilane coupling agent was added with stirring to perform the above surface treatment on the alumina powder. . Next, 7.6% of novolak type epoxy resin (epoxy equivalent: 200), 3.8% of phenol novolak resin (hydroxyl equivalent: 104), 0.5% of triphenylphosphine, 0.4% of carnauba wax, and 0.4% of carbon black. 3% and antimony trioxide 2.0%
Was mixed at room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a molding material.

Comparative Example 2 85.0% of a fused silica powder having a maximum particle size of 100 μm or less was put into a Henschel mixer, and the mixture was stirred as described above.
The above-mentioned fused silica powder was surface-treated by adding 0.4% of C-151 (trade name, manufactured by Nippon Soda Co., Ltd.) of a titanate-based surface treating agent, titacoat series, which is a titanate-based coupling agent. Next, 7.6% of novolak type epoxy resin (epoxy equivalent: 200), 3.8% of phenol novolak resin (hydroxyl equivalent: 104), 0.5% of triphenylphosphine, 0.4% of carnauba wax, and 0.4% of carbon black. 3% and antimony trioxide 2.0
% At room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a molding material.

Comparative Example 3 85.0% of alumina powder having a maximum particle size of 110 μm and an average particle size of 80 μm was placed in a Henschel mixer, and the above-mentioned titanate-based surface treatment agent Titacoat, which is a titanate-based coupling agent of Chemical Formula 3, was stirred. Series C-151
The surface treatment of the alumina powder was performed by adding 0.4% (trade name, manufactured by Nippon Soda Co., Ltd.). Next, 7.6% of novolak type epoxy resin (epoxy equivalent 200), 3.8% of phenol novolak resin (hydroxyl equivalent 104),
0.5% of triphenylphosphine, 0.4% of carnauba wax, 0.3% of carbon black and 2.0% of antimony trioxide are mixed at room temperature, and further mixed at 90 to 110 ° C.
After kneading and cooling, the mixture was pulverized to produce a molding material.

Comparative Example 4 85.0% of a silicon nitride powder having a maximum particle size of 100 μm or less was placed in a Henschel mixer, and the mixture was stirred while stirring.
The above-mentioned silicon nitride powder was surface-treated by adding 0.4% of C-151 (trade name, manufactured by Nippon Soda Co., Ltd.), a titanate-based surface treating agent titacoat series, which is a titanate-based coupling agent. Next, 7.6% of novolak type epoxy resin (epoxy equivalent: 200), 3.8% of phenol novolak resin (hydroxyl equivalent: 104), 0.5% of triphenylphosphine, 0.4% of carnauba wax, and 0.4% of carbon black. 3% and antimony trioxide 2.0
% At room temperature, kneaded and cooled at 90 to 110 ° C., and then pulverized to produce a molding material.

Using the molding materials produced in Examples 1 to 3 and Comparative Examples 1 to 4, transfer was injected into a mold heated to 170 ° C., and the semiconductor chip was sealed and cured to produce a semiconductor device. Various tests were conducted on these semiconductor devices, and the results are shown in Table 1. The epoxy resin composition and the semiconductor encapsulation device of the present invention have improved mechanical properties, excellent moldability, thermal conductivity, moisture resistance, excellent solder heat resistance, and good mold wear resistance. A remarkable effect could be confirmed.

[0032]

[Table 1] * 1: Using a 120-cavity 16-pin P mold,
The molding material was subjected to transfer molding at 170 ° C. for 3 minutes, and the filling property was evaluated. ○: good, △: slightly bad,
X: Bad. * 2: The spiral flow at 175 ° C was measured according to EMMI-I-66. * 3: Transfer molding at 175 ° C, 80 kg / cm ^{2 for} 2 minutes to form molded products (test pieces).
The composition was post-cured at 8 ° C. for 8 hours, and tested according to JIS-K-6911. * 4: A molded product similar to * 2 was made, a test specimen of appropriate size was measured using a thermal analyzer. * 5: The semiconductor encapsulation equipment is a rapid thermal conductivity meter QTM-MD.
(Trade name, manufactured by Showa Denko KK) at room temperature. * 6: A 5.3 × 5.3 mm chip is mounted on a VQFP (12 × 1
(2 × 1.4 mm) package and transfer molding at 175 ° C. for 2 minutes using molding material.
Post-curing was performed at 5 ° C. for 8 hours. The semiconductor encapsulation device thus obtained was subjected to a moisture absorption treatment at 85 ° C., 85% for 48 hours, and then calculated based on the increased weight. Further, this was passed through an air reflow machine (Max240 ° C.), and the presence or absence of external and internal cracks was examined. * 7: 175 ° C by preheating the molding material and using a mold provided with a hard chrome plating material flow hole with a diameter of 0.5 mm
Perform transfer molding. It was evaluated by the number of shots when the hole diameter was worn by 5%.

[0033]

As apparent from the above description and Table 1, the epoxy resin composition and the semiconductor encapsulation device of the present invention have improved mechanical properties, moldability, thermal conductivity, moisture resistance,
It has excellent solder heat resistance and good mold abrasion resistance, and has high reliability with its properties balanced.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 23/31 F term (Reference) 4J002 CC04X CD02W CD05W CD06W CD07W DE147 EC076 EN108 EU118 EU208 EW018 FD017 FD158 GJ02 GQ00 4J036 AA01 AF06 DB06 DC02 DC41 DC46 DD07 FA03 FB08 GA10 HA12 JA07 4M109 AA01 BA01 EA03 EB03 EB04 EB06 EB07 EB08 EB09 EB12 EB19 EC01 EC05 EC06 EC20

Claims (2)

[Claims] (A) a solid epoxy compound having two or more epoxy groups in one molecule; (B) a solid phenolic compound having two or more phenolic hydroxyl groups in one molecule; A titanate coupling agent represented by the general formula: (Wherein, R ¹ and R ² represent an alkyl group, and x and y
Is an integer of 1 or more and satisfies x + y = 4. (D) Alumina powder having a maximum particle size of 100 μm or less and an average particle size of 60 μm or less and (E) a curing accelerator are essential components, and the alumina powder of (D) is 25 to 90 wt. %. An epoxy resin composition, characterized in that it is contained in a proportion of 0.1%. 2. A solid epoxy compound having two or more epoxy groups in one molecule, (B) a solid phenolic compound having two or more phenolic hydroxyl groups in one molecule, and A titanate-based coupling agent represented by the general formula: (Wherein, R ¹ and R ² represent an alkyl group, and x and y
Is an integer of 1 or more and satisfies x + y = 4. (D) Alumina powder having a maximum particle size of 100 μm or less and an average particle size of 60 μm or less and (E) a curing accelerator are essential components, and the alumina powder of (D) is used in an amount of 25 to 9 based on the entire resin composition.
A semiconductor sealing device, wherein a semiconductor chip is sealed with a cured product of an epoxy resin composition containing 0% by weight.