JPH0925329A - Epoxy resin composition and semiconductor device sealed therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition excellent in humidity resistance, soldering-heat resistance and moldability by mixing a specified epoxy resin with a phenolic resin, a specified silane coupling agent, a spherical alumina powder and a cure accelerator as the essential components. SOLUTION: This epoxy resin composition consists essentially of an epoxy resin represented by the formula (wherein n is 0 or an integer of 1 or greater), a phenolic resin, an epoxy silane coupling agent represented by the formula: R<1> -Cn H2n -Si(OR<2> )3 (wherein R<1> is an epoxy atomic group; R<2> is methyl or ethyl; and (n) is 0 or an integer of 1 or greater), 25-90wt.%, based on the total resin composition, spherical alumina powder of a max. particle diameter of 100μm or below and a cure accelerator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to moisture resistance, solder heat resistance,
The present invention relates to an epoxy resin composition excellent in moldability and a semiconductor sealing device.

[0002]

2. Description of the Related Art In recent years, in the field of semiconductor integrated circuits,
At the same time as the development of high integration and high reliability technologies, automation of the mounting process of semiconductor devices has been 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 sealed with a resin composition comprising a conventional epoxy resin such as a novolak type epoxy resin, a novolak type phenol resin and an inorganic filler is subjected to solder bath immersion of the entire device. There is a disadvantage that the moisture resistance is reduced. In particular, when a semiconductor device that has absorbed moisture is immersed, peeling between the sealing resin and the semiconductor chip, or between the sealing resin and the lead frame, and cracking of the internal resin occur, causing significant deterioration in moisture resistance, causing disconnection and moisture due to electrode corrosion. The semiconductor device has a drawback that long-term reliability cannot be guaranteed.

[0004] Further, by filling the inorganic filler at a high level, the proportion of the resin component is reduced, and the resin composition can be made to have a low moisture absorption. There is a drawback that the internal resin crack propagates along the interface to the external resin crack because the interface between the inorganic filler and the inorganic filler increases.

The present invention has been made to solve the above-mentioned drawbacks, and has a small influence of moisture absorption. In particular, it has excellent moisture resistance after solder bath immersion, excellent solder heat resistance, moldability, fluidity, and a sealing resin. Epoxy resin composition that guarantees long-term reliability without peeling between semiconductor chip or encapsulation resin and lead frame, no internal resin cracks, no disconnection due to electrode corrosion, and no leak current due to moisture An object and a semiconductor sealing device are provided.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above-mentioned object, and as a result, by using a specific epoxy resin and a specific silane coupling agent, moisture resistance and solder heat resistance have been improved. It has been found that a resin composition having excellent properties and moldability can be obtained, and the present invention has been completed.

That is, the present invention provides (A) an epoxy resin represented by the following general formula:

[0008]

Embedded image (However, n represents 0 or an integer of 1 or more in the formula) (B) Phenolic resin, (C) Silane coupling agent having an epoxy group represented by the following general formula, to which an organic base is added in an extremely small amount,

[0009]

Embedded image ^{_{R 1 -C n H 2n -Si (}} OR 2) 3 ( wherein R ¹ is an atomic group having an epoxy group, R ²
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A spherical alumina powder having a maximum particle size of 100 μm or less and (E) a curing accelerator are essential components, and the entire resin composition For the above (D)
An epoxy resin composition characterized in that the spherical alumina powder is contained in a proportion of 25 to 90% by weight. Also,
A semiconductor sealing device characterized in that a semiconductor chip is sealed with a cured product of the epoxy resin composition.

Hereinafter, the present invention will be described in detail.

As the epoxy resin (A) used in the present invention, the one represented by the above general formula 5 is used. In addition, a novolak epoxy resin, an epibis epoxy resin, and other known epoxy resins can be used in combination with the epoxy resin.

The (B) phenol resin used in the present invention is not particularly limited as long as it has two or more phenolic hydroxyl groups capable of reacting with the epoxy groups of the epoxy resin (A). As a specific compound, for example,

[0013]

Embedded image (However, n represents 0 or an integer of 1 or more)

[0014]

Embedded image (However, n represents 0 or an integer of 1 or more)

[0015]

Embedded image (However, n represents 0 or an integer of 1 or more)

[0016]

Embedded image (However, n represents 0 or an integer of 1 or more)

[0017]

Embedded image (Where n represents 0 or an integer of 1 or more), and these can be used alone or in combination.

As the silane coupling agent having an epoxy group (C) used in the present invention, those represented by the above-mentioned general formula (6) are used. Specifically, for example,

[0019]

Embedded image

[0020]

Embedded image And the like, and these can be used alone or as a mixture.

It is important to add a very small amount of an organic base to the silane coupling agent. The hydrolyzability can be increased by treating with an organic base.
Examples of the organic base to be treated here include cyclic organic bases such as dimethylamine, diethylamine, pyridine, quinoline and piperidine, and these can be used alone or as a mixture of two or more. The compounding ratio of the organic base is desirably used within the range of 0.05 to 5% by weight based on the silane coupling agent. If the content is less than 0.05% by weight, the hydrolysis of the silane coupling agent cannot be sufficiently promoted, and if it exceeds 5% by weight, the moisture resistance reliability decreases, which is not preferable.

The spherical alumina powder (D) used in the present invention has a low impurity concentration and a maximum particle size of 100 μm or less,
In particular, spherical alumina powder having an average particle size of 30 μm or less is preferably used. If the average particle size exceeds 30 μm, the moisture resistance and moldability are poor, which is not preferable. It is preferable to mix the spherical alumina powder so that the spherical alumina powder is contained in an amount of 25 to 90% by weight based on the total resin composition. If the proportion is less than 25% by weight, the resin composition has a high hygroscopicity and is inferior in moisture resistance after immersion in solder, and if it exceeds 90% by weight, the fluidity becomes extremely poor and the moldability is inferior. When an organic base is added to these spherical alumina powders as a silane coupling agent and immediately treated with a Henschel mixer, a super mixer, or the like, the surface can be uniformly treated, and the effect can be sufficiently exhibited.

The (E) curing accelerator used in the present invention includes a phosphorus-based curing accelerator, an imidazole-based curing accelerator, and D
A wide range of BU-based curing accelerators and other curing accelerators can be used. These can be used alone or in combination of two or more. It is desirable that the curing accelerator is blended in an amount of 0.01 to 5% by weight based on the total resin composition. If the proportion is less than 0.01% by weight, the gel time of the resin composition will be long and the curing characteristics will be poor, and if it exceeds 5% by weight, the fluidity will be extremely poor and the moldability will be poor.
Furthermore, the electrical characteristics are poor and the moisture resistance is poor, which is not preferable.

The epoxy resin composition of the present invention contains the above-mentioned specific epoxy resin, phenolic resin, specific silane coupling agent, spherical alumina powder and curing accelerator as essential components, but does not violate the object of the present invention. In the limit and as required, for example, natural waxes, synthetic waxes, metal salts of straight chain fatty acids, acid amides, esters, paraffins and other releasing agents, antimony trioxide and other flame retardants, carbon black. A colorant such as the above, a rubber-based or silicone-based low stress imparting agent, and the like can be appropriately added and blended.

When the epoxy resin composition of the present invention is prepared as a molding material, the general method is to mix spherical alumina powder with a specific silane coupling agent and an organic base for surface treatment, and then to use the specific epoxy resin described above. , Phenol resin, spherical alumina powder treated with a silane coupling agent, a curing accelerator, and other components are mixed and sufficiently mixed with a mixer or the like, and then melt-mixed with a hot roll or mixed with a kneader. Then, it can be cooled and solidified and crushed to an appropriate size to obtain a molding material. When 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 molding material described above. 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, it is heated and cured, and finally a semiconductor sealing device sealed with this cured product is obtained. The curing by heating is desirably performed by heating to 150 ° C. or more.

[0027]

The epoxy resin composition and the semiconductor encapsulation device of the present invention can be used to absorb water of a resin composition by using a specific epoxy resin, a phenol resin, a specific silane coupling agent, spherical alumina powder and a curing accelerator. Is improved, moldability, fluidity, thermomechanical properties and low stress are improved, the occurrence of resin cracks after solder immersion and solder reflow is eliminated, and moisture resistance deterioration is reduced.

[0028]

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 Spherical alumina powder (with a maximum particle size of 100 μm or less, an average particle size of 20
μm) 77%, fine fused spherical silica powder (average particle size 0.5
μm) 10% was put in a Henschel mixer, and 0.4% of the silane coupling agent of the above chemical formula 12 and 4 × 10 ⁻⁴ % of diethylamine were added to the spherical alumina powder while stirring. Next, 5.7% of an epoxy resin having a dicyclopentadiene skeleton represented by the following formula,

[0030]

Embedded image 1.0% of tetrabromobisphenol A type epoxy resin,
1.0% of the above-mentioned phenolic resin of the formula 7, 2.0% of the phenolic resin of the above-mentioned formula 8, and 0.2 of triphenylphosphine.
%, Carnauba waxes 0.4%, carbon black 0.3
% And antimony trioxide 2.0% at room temperature.
After kneading and cooling at 100100 ° C., the mixture was pulverized to produce a molding material (A).

Example 2 Spherical alumina powder (with a maximum particle size of 100 μm or less, an average particle size of 20
μm) 77%, fine fused spherical silica powder (average particle size 0.5
μm) 10% was put in a Henschel mixer, and 0.4% of the silane coupling agent of the above chemical formula 13 and 4 × 10 ⁻⁴ % of diethylamine were added to the spherical alumina powder for surface treatment while stirring. Next, 5.7% of the epoxy resin having the dicyclopentadiene skeleton used in Example 1, 1.0% of the tetrabromobisphenol A type epoxy resin, 1.0% of the above-mentioned chemical formula 7 phenol resin, and the above-mentioned chemical formula 8 phenol resin 2.0.
%, Triphenylphosphine 0.2%, carnauba wax 0.4%, carbon black 0.3%, antimony trioxide
2.0% was mixed at room temperature, further kneaded and cooled at 70 to 100 ° C., and then pulverized to produce a molding material (B).

Example 3 Spherical alumina powder (with a maximum particle size of 100 μm or less and an average particle size of 20
μm) 77% fine fused spherical silica powder (average particle size 0.5 μ
m) 10% was put in a Henschel mixer, and 0.4% of the silane coupling agent represented by Chemical formula 12 and 4 × 10 ⁻⁴ % of diethylamine were added to the surface of the spherical alumina powder while stirring. Next, 5.7% of the epoxy resin having a dicyclopentadiene skeleton used in Example 1, 1.0% of tetrabromobisphenol A type epoxy resin, 1.0% of the above-mentioned chemical formula 7 phenol resin, and the above-mentioned chemical formula 9 phenolic resin 2.0
%, Triphenylphosphine 0.2%, carnauba wax 0.4%, carbon black 0.3%, antimony trioxide
2.0% was mixed at room temperature, further kneaded and cooled at 70 to 100 ° C., and then pulverized to produce a molding material (C).

Comparative Example 1 Spherical alumina powder (with a maximum particle size of 100 μm or less, an average particle size of 20
μm) 73%, fine fused spherical silica powder (average particle size 0.5
(10 μm) was placed in a Henschel mixer, and 0.4% of the silane coupling agent of the above chemical formula 12 was added with stirring to surface-treat spherical alumina powder. Next, 1.5% of tetrabromobisphenol A type epoxy resin, 8.1% of o-cresol novolac type epoxy resin, 1.7% of the above-mentioned chemical resin of phenol 7 and 3.5 of the above-mentioned chemical resin of phenol 8
%, Triphenylphosphine 0.2%, carnauba wax 0.4%, carbon black 0.3%, antimony trioxide
2.0% was mixed at room temperature, further kneaded and cooled at 70 to 100 ° C., and then pulverized to produce a molding material (D).

Comparative Example 2 Spherical alumina powder (with a maximum particle size of 100 μm or less, an average particle size of 20
μm) 77%, fine fused spherical silica powder (average particle size 0.5
(10 μm) was placed in a Henschel mixer, and 0.4% of the silane coupling agent of the above chemical formula 12 was added with stirring to surface-treat spherical alumina powder. Next, 1.0% of tetrabromobisphenol A type epoxy resin, 5.0% of o-cresol novolak type epoxy resin, 1.2% of the above-mentioned chemical resin of phenol 7 and 2.5 of the above-mentioned chemical formula of phenolic resin 2.5.
%, Triphenylphosphine 0.2%, carnauba wax 0.4%, carbon black 0.3%, antimony trioxide
2.0% was mixed at room temperature, further kneaded and cooled at 70 to 100 ° C., and then pulverized to obtain a molding material (E).

Comparative Example 3 Spherical alumina powder (with a maximum particle size of 100 μm or less, an average particle size of 20
μm) 77%, fine fused spherical silica powder (average particle size 0.5
μm) 10 %% was put in a Henschel mixer, and 0.4% of the silane coupling agent represented by Chemical formula 12 was added to the surface of spherical alumina powder while stirring. Next, Example 1
Epoxy resin containing dicyclopentadiene skeleton used for 5.
7%, tetrabromobisphenol A type epoxy resin 1.
0%, 1.0% phenol of the above-mentioned chemical formula 7, 8% of the above-mentioned chemical formula
Phenolic resin 2.0%, triphenylphosphine 0.2
%, Carnauba waxes 0.4%, carbon black 0.3
% And antimony trioxide 2.0% at room temperature.
The mixture was kneaded and cooled at -100 ° C and then pulverized to produce a molding material (F).

Molding materials (A) to (F) produced in this way
Was transferred into a mold heated to 175 ° C., and the semiconductor chip was sealed and cured to produce a semiconductor sealing device. Various tests were performed on these semiconductor sealing devices, and the results are shown in Table 1. The epoxy resin composition and the semiconductor sealing device of the present invention are excellent in moisture resistance, solder heat resistance, and moldability. Thus, a remarkable effect of the present invention could be confirmed.

[0037]

[Table 1] * 1: Spiral flow measurement (175 ° C.) according to EMMI-I-66. * 2: Koka type flow viscosity (175 ° C). * 3: Prepare a molded product (test piece) obtained by transfer molding at 175 ° C, 80 kg / cm ² for 2 minutes, and
Post-curing was carried out at 8 ° C. for 8 hours, and the test was conducted according to JIS-K-6911. * 4: A molded article similar to * 3 was prepared, post-cured at 175 ° C for 8 hours, and a test piece of an appropriate size was measured using a thermomechanical analyzer. * 5: Make a molded product (test piece) with a diameter of 100 mm and a thickness of 2.5 mm.
It measured using the thermal conductivity meter. * 6, * 7: VQFP 80pin (12
× 12 × 1.4mm thickness) package and use molding material
After transfer molding at 175 ° C for 2 minutes,
Post-curing was performed for a period of time. The semiconductor encapsulation device thus obtained
After the moisture absorption treatment at 85 ° C. and 85% for 48 hours, it was calculated by the increased weight. Further, this was passed through an air reflow machine (Max 240 ° C.) to investigate the presence of external and internal cracks.

[0038]

As is apparent from the above description and Table 1, the epoxy resin composition and the semiconductor encapsulation device of the present invention are excellent in moisture resistance, solder heat resistance, moldability, and filling of thin packages and the like. It is also excellent in performance, is less affected by moisture absorption, can significantly reduce disconnection due to electrode corrosion, generation of leak current due to moisture, and the like, and can guarantee reliability for a long period of time.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location H01L 23/29 H01L 23/30 R 23/31

Claims (2)

[Claims] (A) an epoxy resin represented by the following general formula: (In the formula, n represents 0 or an integer of 1 or more) (B) Phenolic resin, (C) Silane coupling agent having an epoxy group represented by the following general formula, to which an organic base is added in a very small amount: Embedded image R ¹ —C _n H _2n —Si (OR ² ) ₃ (wherein R ¹ is an atomic group having an epoxy group, R ²
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A spherical alumina powder having a maximum particle size of 100 μm or less and (E) a curing accelerator are essential components, and the entire resin composition For the above (D)
An epoxy resin composition comprising 25 to 90% by weight of the spherical alumina powder of 1. (A) an epoxy resin represented by the following general formula: (In the formula, n represents 0 or an integer of 1 or more) (B) Phenolic resin, (C) Silane coupling agent having an epoxy group represented by the following general formula, to which an organic base is added in a very small amount: Embedded image R ¹ —C _n H _2n —Si (OR ² ) ₃ (wherein R ¹ is an atomic group having an epoxy group, R ²
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A spherical alumina powder having a maximum particle size of 100 μm or less and (E) a curing accelerator are essential components, and the entire resin composition For the above (D)
A semiconductor encapsulation device, wherein a semiconductor chip is encapsulated with a cured product of an epoxy resin composition containing the spherical alumina powder of 25 to 90% by weight.