JP2906599B2 - Resin composition for semiconductor encapsulation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a resin composition for semiconductor encapsulation excellent in high-temperature reliability and humidity resistance reliability.

<Prior Art> A semiconductor element is sealed with various sealing materials to protect it from the external environment and mechanical shock and to electrically insulate it.

As a sealing material and a sealing method for this purpose, a hermetic seal made of metal or ceramic and a resin seal made of phenol resin, silicone resin and epoxy resin have been conventionally proposed. From the viewpoint, resin sealing with epoxy resin is mainly used.

The properties required of the epoxy resin composition for semiconductor encapsulation include reliability, and among others, moisture resistance reliability and high temperature reliability are important.

The moisture resistance reliability referred to here means that when a resin-encapsulated semiconductor is left in a high-temperature, high-humidity environment, moisture enters through an interface between the encapsulation resin or the encapsulation resin and the lead frame, and Is to prevent failure.

The high-temperature reliability is to prevent the semiconductor from being damaged by the effect of the brominated epoxy compound added as a flame retardant when the resin-encapsulated semiconductor is left at a high temperature of 150 ° C. or higher.

In recent years, as the degree of integration of semiconductors has improved, higher levels of high-humidity reliability and high-temperature reliability have been required.

For this reason, means for improving the reliability of the sealing resin are being studied.For example, by reducing impurities contained in components such as an epoxy resin and a curing agent, and by purifying the sealing resin, moisture resistance is improved. Method for improvement (JP-A-57-2122)
No. 24) has been proposed.

<Problems to be Solved by the Invention> However, although purifying the sealing resin by reducing impurities such as an epoxy resin and a curing agent is effective in improving moisture resistance, the high purity of the sealing resin is achieved. There was a problem that there was a limit to conversion.

Therefore, an object of the present invention is to solve the above-mentioned problems of the epoxy resin composition and provide a resin composition for semiconductor encapsulation having excellent reliability such as moisture resistance and high-temperature reliability. An object of the present invention is to enable production of a sealing semiconductor.

<Means for Solving the Problems> The present inventors have achieved the above object by adding sodium antimonate and found that a resin composition meeting the purpose can be obtained, and arrived at the present invention. .

That is, the present invention comprises an epoxy resin (A), a curing agent (B) and a filler (C) as essential components, and further has the following general formula (I) (Na ₂ O) xSb ₂ O ₅ .nH ₂ O (I (Where x represents 0.1 to 5.0 and n ≧ 0). A resin composition for semiconductor encapsulation, comprising 0.02 to 30% by weight of sodium antimonate (D) represented by the following formula: Is a semiconductor device in which a semiconductor element is sealed.

 Hereinafter, the configuration of the present invention will be described in detail.

The epoxy resin (A) in the present invention is not particularly limited as long as it has two or more epoxy groups in one molecule, and specific examples thereof include, for example, cresol novolak type epoxy resin, biphenyl type epoxy resin, bisphenol Examples include A-type epoxy resin, linear aliphatic epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, and spiro ring-containing epoxy resin.

In the present invention, the compounding amount of the epoxy resin (A) is usually preferably in the range of 5 to 25% by weight. If it is less than 5% by weight, the moldability and adhesiveness are insufficient. It is not preferable because the expansion coefficient becomes large and it becomes difficult to reduce the stress.

The curing agent (B) in the present invention is an epoxy resin (A)
There is no particular limitation as long as it reacts with and cures. Specific examples thereof include novolak resins such as phenol novolak and cresol novolak, bisphenol compounds such as bisphenol A, maleic anhydride, phthalic anhydride, and pyroanhydride. Acid anhydrides such as melitic acid and aromatic amines such as metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone and the like can be mentioned. For sealing semiconductor devices, novolak resins such as phenol novolak and cresol novolak are preferably used from the viewpoint of heat resistance, moisture resistance and storage stability, and two or more curing agents may be used in combination depending on the application.

In the present invention, the compounding amount of the curing agent (B) is usually from 2 to
15% by weight. Furthermore, the mixing ratio of the epoxy resin (A) and the curing agent (B) is such that the chemical equivalent ratio of (B) to (A) is 0.6 to 1.5, particularly 0.1, from the viewpoint of mechanical properties and moisture resistance.
It is preferably in the range of 8 to 1.3.

In the present invention, a curing catalyst may be used to accelerate the curing reaction between the epoxy resin (A) and the curing agent (B). The curing catalyst is not particularly limited as long as it promotes the curing reaction. For example, 2-methylimidazole, 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methyl Imidazole compounds such as imidazole and 2-heptadecyl imidazole, triethylamine, benzyldimethylamine, α-methylbenzyldimethylamine,
Tertiary amine compounds such as-(dimethylaminomethyl) phenol, 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5,4,0) undecene-7, zirconium tetramethoxide, zirconium Tetrapropoxide, tetrakis (acetylacetonato)
Organometallic compounds such as zirconium and tri (acetylacetonato) aluminum; and organic phosphine compounds such as triphenylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, tri (p-methylphenyl) phosphine, and tri (nonylphenyl) phosphine. Can be Among them, an organic phosphine compound is preferable from the viewpoint of reliability and moldability, and triphenylphosphine is particularly preferably used.

These curing catalysts may be used in combination of two or more depending on the use, and the addition amount thereof is preferably in the range of 0.1 to 10 parts by weight based on 100 parts by weight of the epoxy resin (A).

As the filler (C) in the present invention, fused silica,
Examples include crystalline silica, calcium carbonate, magnesium carbonate, alumina, magnesia, clay, talc, calcium silicate, titanium oxide, asbestos, and glass fibers. Among them, fused silica is preferably used because it has a large effect of lowering the linear expansion coefficient and is effective in reducing stress.

The amount of the filler (C) added is 70 to 90% by weight of the whole.
Is preferred in terms of low stress.

Antimonate soda (D) in the present invention, the following general formula _{(I) (Na 2 O)} xSb 2 O 5 · nH 2 O (I) ( where x is 0.1 to 5.0, indicating the n ≧ 0.) Although it is not particularly limited as long as it is represented by the following, x is preferably 0.2 to 2.0, more preferably 0.4 to 1.0. Further, it may contain water of crystallization, but is preferably a high-temperature-treated one that does not contain water of crystallization.

In addition, about the addition, it can be added as a part of the flame retardant auxiliary and the filler, and the addition amount is 0.02 to 30% by weight,
Preferably 0.02 to 10% by weight, more preferably 0.02 to 5%
If it is less than 0.02% by weight, the effect of improving high-temperature reliability and moisture resistance reliability is insufficient, and if it is more than 30% by weight, the fluidity decreases.

The resin composition of the present invention includes a halogen compound such as a halogenated epoxy resin, a flame retardant such as a phosphorus compound, a flame retardant auxiliary such as antimony trioxide, a colorant such as carbon black and iron oxide, a silicone rubber, and a styrene-based block. Elastomers such as copolymers, olefin copolymers, modified nitrile rubber, modified polybutadiene rubber, thermoplastic resins such as polyethylene, coupling agents such as silane coupling agents, long chain fatty acids, metal salts of long chain fatty acids, Release agents such as esters of long chain fatty acids, amides of long chain fatty acids, paraffin wax and the like, and crosslinking agents such as organic peroxides can be optionally added.

The epoxy resin composition of the present invention is preferably melt-kneaded, and is produced by melt-kneading using a known kneading method such as a Banbury mixer, a kneader, a roll, a single-screw or twin-screw extruder and a co-kneader. .

<Example> Hereinafter, the present invention will be specifically described with reference to examples.

Examples 1 to 5 and Comparative Examples 1 and 2 Dry blending was performed by a mixer at the composition ratios shown in Table 1. This was heated and kneaded for 5 minutes using a mixing roll having a roll surface temperature of 90 ° C., then cooled and pulverized to produce an epoxy resin composition.

Using this composition, a 44-pin QFP encapsulating the simulated device was molded at 175 ° C. for 2 minutes by low-pressure transfer molding, and post-cured at 175 ° C. for 5 hours.

USPCBT was performed at 120 ° C, 85% RH, and bias voltage of 20V using 44-pin QFP after post-curing to measure humidity resistance reliability.
The time at which the cumulative failure rate reached 50% was determined.

For high temperature reliability measurement, 44pinQ after post cure
Using FP, we performed a standing test at a high temperature of 210 ° C.
Anything exceeding Ω is treated as a failure, and the cumulative failure rate is 50
% Time was determined.

As can be seen from Table 1, Examples 1 to 5 using the sodium antimonate (D) of the present invention are excellent in high-temperature reliability and humidity resistance reliability. Among them, Examples 3, 4, and 5 using a biphenyl-type epoxy resin are particularly excellent in high-temperature reliability.

In contrast, the sodium antimonate of the present invention (D)
In Comparative Examples 1 and 2 containing no, the high-temperature reliability and the humidity resistance reliability were both inferior.

<Effect of the Invention> The resin composition for encapsulating a semiconductor of the present invention is excellent in high-temperature reliability and humidity resistance reliability.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-50257 (JP, A) JP-A-51-44154 (JP, A) JP-A-63-215762 (JP, A) JP-A-62 43458 (JP, A) JP-A-62-127347 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C08L 63/00-63/10 C08K 3/22 H01L 23/29

Claims (2)

(57) [Claims] An epoxy resin (A), a curing agent (B) and a filler (C) are essential components, and the following general formula (I) (Na ₂ O) xSb ₂ O ₅ .nH ₂ O (I (Where x represents 0.1 to 5.0 and n ≧ 0). A resin composition for semiconductor encapsulation containing sodium antimonate (D) represented by the following formula: 0.02 to 30% by weight. 2. A semiconductor device in which a semiconductor element is sealed with the resin composition for semiconductor sealing according to claim 1.