JPH10114815A - Epoxy resin composition and sealed semiconductor device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin compsn. excellent in moisture resistance by mixing an anthracene-type epoxy resin represented by a specific formula, a phenol resin, an epoxidized silane coupling agent, a crystal silica powder, and a cure accelerator. SOLUTION: Crystal silica powder (20-90wt.%) having a max. particle size of 150μm or lower is charged into a mixer, and a silane coupling agent represented by formula I (wherein R<5> is an epoxidized group; R<6> is methyl or ethyl; and (n) is 0, 1, or higher) and a base (e.g. diethylamine) in an amt. of 0.05-5wt.% of the coupling agent are added to the silica powder under stirring to treat the surface of the powder. The surface-treated silica powder is mixed with an anthracene-type epoxy resin represented by formula II (wherein R<1> to R<4> are each Cn H2n+1 ; and (m) is 0, 1, or higher), a biphenyl-type epoxy resin, a phenol resin having at least two epoxy-reactive hydroxyl groups, 0.01-5wt.% cure accelerator (e.g. triphenylphosphine), and additives such as a mold release agent, a flame retardant, and a colorant at normal temp., kneaded at 70-100 deg.C, cooled, and ground to give an epoxy resin compsn.

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 excellent in moisture resistance, solder heat resistance, and 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 a flat package type semiconductor device is mounted on a circuit board, soldering has conventionally been performed for each lead pin, but recently, a solder immersion 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. The semiconductor device has a drawback that long-term reliability cannot be guaranteed.

[0004] Further, a commonly used epoxy resin having a naphthalene skeleton shown below is:

[0005]

Embedded image Compared to conventional novolak-type epoxy resins and biphenyl-type epoxy resins, they have the advantage of high toughness, but have a low epoxy equivalent, and it has been difficult to reduce the moisture absorption of resin compositions using these.

The present invention has been made in order to solve the above-mentioned disadvantages, 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.

[0007]

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 moldability and the like can be obtained, and the present invention has been completed.

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

[0009]

Embedded image (Wherein, R ^{1 to} R ⁴ are the same or different
_{m represents an} H _{2m + 1} group, m represents an integer of 0 or 1 or more) (B) a phenolic resin, (C) a silane coupling agent having an epoxy group represented by the following general formula,

[0010]

Embedded image ^{_{R 5 -C n H 2n -Si (}} OR 6) 3 ( where, wherein R ⁵ is an atomic group having an epoxy group, R ⁶
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A crystalline silica powder having a maximum particle size of 150 μm or less and (E) a curing accelerator are essential components. (D)
An epoxy resin composition comprising the crystalline silica powder of 25 to 90% by weight. A semiconductor sealing device is 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, those represented by the aforementioned general formula (6) are used. Specific compounds include, for example,

[0013]

Embedded image Is mentioned. In addition, a novolak-based epoxy resin, an epibis-based epoxy resin, a biphenyl-type epoxy resin, and other commonly known epoxy resins can be used in combination with the epoxy resin.

The phenolic resin (B) 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 group of the epoxy resin (A). As a specific compound, for example,

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

[0018]

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

[0019]

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 general formula (7) are used. Specifically, for example,

[0021]

Embedded image

[0022]

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

A very small amount of an organic base can be added to the silane coupling agent. Hydrolysis can be enhanced by treating with an organic base.Examples of the organic base to be added and treated here include cyclic organic bases such as dimethylamine, diethylamine, pyridine, quinoline, and piperidine, which can be used alone or in combination. Can be used. 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 amount 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 is undesirably lowered.

As the crystalline silica powder (D) used in the present invention, a crystalline silica powder having a low impurity concentration, a maximum particle diameter of 150 μm or less, 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 poor, which is not preferable. The compounding ratio of the crystalline silica powder is preferably such that it is contained at 25 to 90% by weight based on the whole resin composition. If the proportion is less than 25% by weight, the resin composition has a high hygroscopicity, is inferior in moisture resistance after solder immersion, and
If it exceeds 90% by weight, the fluidity becomes extremely poor and the moldability is poor, which is not preferred. When an organic base is added to these crystalline silica powders as a silane coupling agent and immediately treated with a Henschel mixer, a super mixer or the like, a uniform surface treatment can be performed, 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
BU-based curing accelerators and other curing accelerators can be widely used. These can be used alone or in combination of two or more. It is desirable that the curing accelerator is 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 will be long and the curing properties will be poor. If it exceeds 5% by weight, the fluidity will be extremely poor and the moldability will be poor.
Further, the electrical properties are also 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, phenol resin, specific silane coupling agent, crystalline silica powder and a curing accelerator as essential components, but does not violate the object of the present invention. At the limit,
If necessary, for example, natural waxes, synthetic waxes, metal salts of linear fatty acids, acid amides, esters,
A release agent such as paraffin, a flame retardant such as antimony trioxide, a coloring agent such as carbon black, a rubber-based or silicone-based low-stress imparting agent, 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 as follows: the specific epoxy resin, phenol resin, crystalline silica powder treated with a silane coupling agent, a curing accelerator and other components Is mixed sufficiently by a mixer or the like, and further subjected to a melt-mixing treatment by a hot roll or a mixing treatment by a kneader or the like, and then solidified by cooling and pulverized to an appropriate size to obtain 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.

The semiconductor sealing 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, 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.

The epoxy resin composition and the semiconductor encapsulation device of the present invention use a specific epoxy resin, a phenol resin, a specific silane coupling agent, a crystalline silica powder, and a curing accelerator to obtain a water absorbing property of the resin composition. This improves moldability, fluidity, thermomechanical properties and low stress, eliminates resin cracks after solder immersion and solder reflow, and reduces moisture resistance deterioration.

[0030]

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 84% of crystalline silica powder (maximum particle size of 150 μm or less) was put into a Henschel mixer, and 0.4% of the above-mentioned silane coupling agent of formula (15) and 4 × 10 ^{-4 of} diethylamine were stirred with stirring.
%, And the surface treatment of the crystalline silica powder was performed.

Next, 1.6% of the above-mentioned anthracene-type epoxy resin of the formula (9), 4.5% of the biphenyl-type epoxy resin of the following formula (16),

[0033]

Embedded image 1.5% of tetrabromobisphenol A type epoxy resin,
1.0% of the phenolic resin of the aforementioned chemical formula 9,
Phenolic resin 4.2%, triphenylphosphine 0.2
%, Carnauba waxes 0.4%, carbon black 0.3
%, And 2.0% of antimony trioxide were mixed at room temperature, kneaded and cooled at 70 to 100 ° C., and then pulverized to produce a molding material (A).

Example 2 84% of crystalline silica powder (maximum particle size of 150 μm or less) was put into a Henschel mixer, and 0.4% of the above-mentioned silane coupling agent of formula (15) and 4 × 10 ^{-4 of} diethylamine were stirred with stirring.
%, And the surface treatment of the crystalline silica powder was performed.

Next, 1.6% of the above-mentioned anthracene-type epoxy resin of Chemical Formula 8, 4.5% of the biphenyl-type epoxy resin of Chemical Formula 16 used in Example 1, and tetrabromobisphenol A
1.5% epoxy resin, phenol resin of Chemical formula 9
1.0%, 4.2% of the above-mentioned phenolic resin of formula 11, 0.2% of triphenylphosphine, 0.4 of carnauba wax
%, Carbon black 0.3%, and 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).

Comparative Example 1 84% of crystalline silica powder (maximum particle size of 150 μm or less) was put into a Henschel mixer, and 0.4% of the above-mentioned silane coupling agent of Chemical Formula 14 and 4 × 10 ^{-4 of} diethylamine were stirred with stirring.
%, And the surface treatment of the crystalline silica powder was performed.

6.1% of the biphenyl type epoxy resin of Chemical formula 16 used in Example 1, 1.5% of the tetrabromobisphenol A type epoxy resin, 1.0% of the phenol resin of Chemical formula 9, 4.2% of the phenol resin of Chemical formula 10, and triphenylphosphine 0.2%, carnauba waxes 0.4%, carbon black 0.3% and antimony trioxide 2.0% were mixed at room temperature, kneaded and cooled at 70 to 100 ° C., and pulverized to produce a molding material (C).

COMPARATIVE EXAMPLE 2 84% of crystalline silica powder (maximum particle size of 150 μm or less) was placed in a Henschel mixer, 0.4% of the above-mentioned silane coupling agent of Chemical formula 14 and 4 × 10 ^{-4 of} diethylamine with stirring.
%, And the surface treatment of the crystalline silica powder was performed.

The biphenyl type epoxy resin of formula 16 used in Example 1 was 4.5%, the tetrabromobisphenol A type epoxy resin was 1.5%, the naphthalene type epoxy resin shown in formula 5 was 1.6%, and the phenol resin of formula 9 was 1.0%. ,
4.2% of the above-mentioned phenol resin of formula 11, 0.2% of triphenylphosphine, 0.4% of carnauba wax, 0.3% of carbon black and 2.0% of antimony trioxide were mixed at room temperature, and kneaded and cooled at 70 to 100 ° C. This was pulverized to produce a molding material (D).

The molding materials (A) to (D) thus produced
Was transferred into a mold heated to 170 ° C., and the semiconductor chip was sealed and cured to manufacture 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.

[0041]

[Table 1] * 1: Transfer molded at 175 ° C., 80 kg / cm ² , 2 minutes to form a molded product (test piece), post-cured at 175 ° C. for 8 hours, and tested according to JIS-K-6911. * 2: A molded article similar to * 1 was prepared, post-cured at 175 ° C for 8 hours, a test piece of appropriate size was measured using a thermomechanical analyzer. * 3, * 4: A TO-220 (9 × 14 × 4 mm) package which was transfer-molded at 175 ° C. for 2 minutes using a molding material was post-cured at 175 ° 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. After immersion in a solder bath (Max 260 ° C.), the presence or absence of peeling and opening was examined.

[0042]

As is clear 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, are less affected by moisture absorption, and This can significantly reduce disconnection due to corrosion and generation of leakage current due to moisture, and can guarantee reliability for a long period of time.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 23/29 H01L 23/30 R 23/31

Claims (2)

[Claims] (A) An anthracene epoxy resin represented by the following general formula: (Wherein, R ^{1 to} R ⁴ are the same or different
The _m H _{2m + 1} group, m represents 0 or an integer of 1 or more) (B) a phenolic resin, (C) a silane coupling agent having an epoxy group represented by the following general formula, ## STR2 ## R ^{5 _{-C n H 2n -Si (OR 6}} ) 3 ( where, wherein R ⁵ is an atomic group having an epoxy group, R ⁶
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A crystalline silica powder having a maximum particle size of 150 μm or less and (E) a curing accelerator are essential components. (D)
An epoxy resin composition comprising the crystalline silica powder of 25 to 90% by weight. (A) an anthracene epoxy resin represented by the following general formula: (Wherein, R ^{1 to} R ⁴ are the same or different
The _m H _{2m + 1} group, m represents 0 or an integer of 1 or more) (B) a phenolic resin, (C) a silane coupling agent having an epoxy group represented by the following general formula, ## STR4 ## R ^{5 _{-C n H 2n -Si (OR 6}} ) 3 ( where, wherein R ⁵ is an atomic group having an epoxy group, R ⁶
Represents a methyl group or an ethyl group, and n represents an integer of 0 or 1 or more.) (D) A crystalline silica powder having a maximum particle size of 150 μm or less and (E) a curing accelerator are essential components. (D)
A semiconductor chip is sealed with a cured product of an epoxy resin composition containing 25 to 90% by weight of the crystalline silica powder of (1).