JPS6189221A - Epoxy resin composition for encapsulation of semiconductor - Google Patents

Abstract

PURPOSE:To provide the titled composition having low stress and excellent moldability, moisture-resistance, and crack-resistance in thermal shock, by reacting and fixing a polyalkylene glycol diglycidyl ether with a resin component. CONSTITUTION:The objective composition contains a mixture prepared by heating and melting (A) an epoxy resin hardener or an epoxy resin and (B) a polyalkylene glycol diglycidyl diether in the presence of (C) one or more components selected from tertiary amine or its derivative, an organic phosphine compound, an organic Al compound, a titanium compound, and an acid. The component B is preferably the compound of formula I [m and n are integer of >=2; R1 and R2 are group of formula II (l is 2-12), cyclohexylene, etc.] and especially having a molecular weight of 300-1,000.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a low stress epoxy resin composition that has excellent crack resistance when subjected to thermal shock and moisture resistance, and its characteristics are as follows. After the polyalkylene glycol diglycidyl ether is uniformly dispersed in the resin, it is reacted and fixed with the resin component.

[Prior art]

In recent years, advances in semiconductor-related technology have been remarkable, and the degree of integration of LSIs has been improving year by year, with interconnections becoming finer and chip sizes becoming larger. This trend is reflected in resin-sealed LS
Failures such as I/M wiring deformation, pad page cracks, and resin cracks became more serious. In order to solve these problems, what is currently required of resins for semiconductor encapsulation are:
It reduces stress.

Epoxy resin compositions are widely used for semiconductor encapsulation because they have better moisture resistance than phenol resin compositions and polyester resin compositions. Conventionally, in order to obtain a low stress epoxy resin composition, synthetic rubber was used (Japanese Patent Application Laid-Open No. 58-1769).
58, JP-A-57-180626, JP-A-58-17
4416) and the use of silicones (Unexamined Japanese Patent Publication No. 58-21
0920. JP-A-57-3821) has been studied, but all of them have problems such as poor moldability (especially curability, moldability, and mold release properties) and impairing the moisture resistance of the epoxy resin.

[Purpose of the invention]

The present invention was developed as a result of research aimed at obtaining a low-stress epoxy resin composition with excellent moldability and moisture resistance, which could not be obtained conventionally by using synthetic rubber or silicones. We have discovered that by reacting and fixing ether with a resin component, a low stress epoxy resin composition can be obtained that has excellent moldability, moisture resistance, and crack resistance when subjected to thermal shock. be.

[Structure of the invention]

The present invention provides (1) an epoxy resin, a curing agent, a curing accelerator, a filler, and a mold release agent, characterized in that it contains a curing agent for epoxy resin or a heat-melted mixture of epoxy resins and polyalkylene glycol diglycidyl ether; (2) A curing agent for epoxy resin or epoxy resin and polyalkylene glycol diglycidyl ether, a tertiary amine or its derivative, an organic phosphine compound, An epoxy resin, a curing agent, a curing accelerator, a filler, a release material, characterized by containing a mixture heated and melted in the presence of one or more selected from organoaluminum compounds, titanium compounds, and acids. This is an epoxy resin composition for semiconductor encapsulation that includes a molding agent, a surface treatment agent, etc.

The term "polyalkylene glycol diglycidyl ether" as used herein refers to all compounds represented by the following general formula.

(m%n is an integer of 2 or more, in the formula, Ro, R2Fi, -C
tH2t-(t = 2-12), cyclohexylene,
The molecular weight of alkylene glycol (representing naphthylene, biphenylene, phenylene substituted with an alkyl group, alkoxy group, halogen, etc.) is 200 to 1.
0Q000, preferably 200 to IQ000, particularly preferably 30o to Looo. Examples of such substances include polyethylene glycol diglycidyl, polypropylene glycol diglycidyl ether, and the like.

Such polyalkylene glycol diglycidyl ether has excellent compatibility with hardening agents for epoxy resins and epoxy resins, and not only can be uniformly dispersed, but also can be heated and melted and mixed in the absence or presence of a catalyst. It reacts and immobilizes easily. By using this, it is possible to obtain a low-stress epoxy resin composition in which polyalkylene glycol diglycidyl ether does not dissolve out of the resin, has excellent moldability, and has excellent crack resistance when subjected to thermal shock. did it.

Examples of reaction catalysts include tertiary amine or its derivatives trimethylamine, triethylamine, 2.3.4.6
．． 7.8.9.10-octahydro-pyramide (1,
2-1) Azepine, etc. or quaternary ammonium salts thereof ■Organic phosphines/compounds (a) Primary, secondary, and tertiary phosphines: octylphosphine, diphenylphosphine, phthylphenylphosphine, tricyclohexylphosphine, triphenylphosphine etc. (b) Betaine-type adducts of organic tertiary phosphine and compounds having a π bond: maleic anhydride-triphenylphosphine adduct, thioisocyanate-triphenylphosphine adduct, diazodiphenylmethane-triphenylphosphine adduct, etc. (e ) Organic 7h *2') A
Salt: (f63 PCH2Si!')" CLe.

(1213PEt)'9 Iθ, Cg3PEt)Φ
Breetc■Organoaluminum compound (a) At(OR)3 (R: H, alkyl group, aryl group, aryl group-containing hydrocarbon group) Nialuminum isopropoxide, aluminum n-butoxide, aluminum tert-butoxide, aluminum see -
Butyrate, aluminum benzoate stopper) β-diketone complexes of aluminum (aluminum chelate) Nialuminum acetylacetonate, aluminium trifluoroacetylacetonate, aluminum pentafluoroacetylacetonate, etc. ■Titanium compounds butyl titanate, titanium white, etc. ■Acids Para Examples include toluenesulfonic acid.

The curing agent mentioned here is preferably phenol novolacs, but may also include acid anhydrides and amines. These may be used alone or in combination. Phenol novolacs refer to all compounds containing a phenolic hydroxyl group or a derivative thereof in the novolak skeleton. Phenols (phenol, alkylphenol, resorcinol, etc.)
It includes not only single-component novolaks, but also co-condensed novolacs with any combination of phenols, and co-condensed novolaks with phenols and other resins.

Moreover, the epoxy resin referred to herein refers to all resins having an epoxy group. For example, it refers to bisphenol type epoxy resin, novolak type epoxy resin, triazine nucleus-containing epoxy resin, etc.

In addition, polyalkylene glycol diglycidyl ether/
As the ratio of resin components (epoxy resins, curing agents) increases, the stress becomes lower, but the reactivity of the resin components (epoxy resins, curing agents) decreases. The characteristics can be maximized by selecting the mixing ratio, molecular weight, and usage ratio of polyalkylene glycol diglycidyl ether/resin components (epoxy resins, curing agents) and the usage ratio in the composition depending on the purpose. . In particular, for epoxy resin low-pressure encapsulation molding materials, it is desirable to use phenol novolaks as the resin component, and the ratio of polyalkylene glycol diglycidyl ether/phenol novolacs is 4 in terms of the molar ratio of 10H epoxy groups.
It is desirable that the proportion of polyalkylene glycol diglycidyl ether used in the °-481 molding material is 0.1 to 5% by weight, and that the molecular weight of the phenol novolak is 500 or less.

In a range other than the above, disadvantages such as poor moldability may occur.

〔Effect of the invention〕

By following the method of the present invention, it is possible to obtain a low-stress epoxy resin composition that has excellent moldability, moisture resistance, and crack resistance when subjected to thermal shock. especially,
In today's world, where it is expected that plastic packaging will increasingly be used in semiconductor encapsulation applications, and where plastics are required to have lower stress, the present invention will play an extremely important role in industry.

〔Example〕

The following is an explanation using a study example of a molding material for semiconductor encapsulation. All parts used in the examples are parts by weight. The examples according to the present invention are superior in moldability, moisture resistance, and crack resistance compared to comparative examples according to the prior art, and have high added value that can be used industrially.

The polyalkylene glycol diglycidyl ether used in this example is as follows.

A: Polypropylene glycol diglycidyl ether (
Epoxy Todoroki 1190, viscosity 45 cps) B: Polypropylene glycol diglycidyl ether (Epoxy equivalent 320, viscosity 75 cps) C: Polyethylene glycol diglycidyl ether (Epoxy equivalent 1501, viscosity 25 cps) D = Polyethylene glycol diglycidyl ether (Epoxy equivalent 285 , viscosity 180c
ps) Also, the reaction catalyst used in this example is as follows.

Catalyst α: ) IJ Phenylphosphine catalyst β Nialuminum acetylacetonato catalyst γ: 2.3.4.6.
7.8.9.10-octahydrobyramide (1,2-
a) Acepine Examples 1 to 6 Part X of polyalkylene glycol diglycidyl ether and part Y of 7-enol novolac (manufactured by Sumitomo Bakelite) were heated and mixed at 150°C for 1 hour in the presence and absence of a reaction catalyst, and then cooled and ground. A seed modified curing agent was obtained. To these modified hardening agents, 70 parts of fused silica (manufactured by Tatsumori), 0.4 parts of surface treatment agent (Nippon Unicar A-186), part of the above-mentioned phenol novolak (10-y), and epoxy resin (Asahi Chipa: EC) were added.
N-1273) 20 parts, curing accelerator (KAI Kasei P
P-360/Shikoku Kasei Rei = 9/1) 0.2 parts, pigment (Mitsubishi Kasei) 0.5 parts, mold release agent (Hoechst Japan Hoechst OP/Hex) S = 1/1) 0.4 parts After addition and mixing, the mixture was kneaded in a conee-gee to obtain six types of epoxy resin compositions.

As a result of measuring the moldability and crack resistance of these molding materials, it was found that they were superior to the comparative examples as shown in Table 1. Moreover, the more polyalkylene glycol diglycidyl ether is added, the better the crack resistance is, but when it is too much, the moldability is poor.

Examples 7 to 12 Part x of polyalkylene glycol diglycidyl ether and 1 part of epoxy resin (Asahi Chipa: ECN-1273) were heated and mixed at 150°C for 1 hour in the presence or absence of a reaction catalyst, then cooled and pulverized to form 6 types. A modified epoxy resin was obtained. To these modified epoxy resin, 70 parts of fused silica, 0.4 part of surface treatment agent, part of the above-mentioned epoxy resin (20-z), 10 parts of phenol novolac, 2 parts of curing accelerator α, and 0.0 parts of pigment were added.
Materials were prepared in the same manner as in Examples 1 to 6 using 5 parts of mold release agent and 0.4 parts of mold release agent (all the same raw materials as in Examples 1 to 6). As a result of measuring the moldability and crack resistance of these molding materials, it was found that they were superior to the comparative examples as shown in Table 2.

Comparative Example: 70 parts of fused silica, 20 parts of epoxy resin, 10 parts of phenol novolak, 0.4 parts of surface treatment agent, curing accelerator α2
1 part, 5 parts of pigment α, and 0.4 part of mold release agent (all the same raw materials as in Examples) were mixed and kneaded in a conee-gee to obtain an epoxy resin composition. As shown in the table, the moldability, crack resistance and moisture resistance of this molding material are significantly inferior to those of the Examples in terms of crack resistance.

*1.16 Pin DIP is judged based on the degree of occurrence of paris on the lead bin when molding )D*2TCT, 16 pin DIP sealed with a simulated element of 4 x 9vts at -65°C (30 minutes)
``Thermal shock at room temperature (5 minutes) and 150℃ (30 minutes) for 20 minutes.
Judging by the number of cracks generated/total number given by 0 cycles *3TST14#
Apply 200 cycles of thermal shock at 0°C (2 minutes) and judge by the number of cracks generated/total number *4 Moisture resistance, 16pinD sealed with aluminum simulated element
IP was stored for 1000 hours at 135℃ and 100cm, and judged based on defective rate/total number due to aluminum corrosion.

Claims (2)

[Claims] (1) An epoxy resin composition for semiconductor encapsulation, comprising a heat-melted mixture of a curing agent for epoxy resins or epoxy resins and polyalkylene glycol diglycidyl ether. (2) A curing agent for epoxy resins or epoxy resins and polyalkylene glycol diglycidyl ether are combined with one or two selected from tertiary amines or derivatives thereof, organic phosphine compounds, organic aluminum compounds, titanium compounds, and acids. An epoxy resin composition for semiconductor encapsulation, comprising a mixture heated and melted in the presence of more than one species.