JPH0625464A - Filler and semiconductor sealing resin composition containing the same - Google Patents

Abstract

PURPOSE:To obtain a filler having high thermal conductivity and low thermal stress properties and suited for a semiconductor sealing resin composition. CONSTITUTION:This filler mainly consists of nitrogenous silica glass particles having a chemical composition of SiO2(1-x)N(4/3)x (wherein 0.003<=x<=0.75). An epoxy resin is mixed with a curing agent therefor and the filler to obtain the objective composition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a filler and a resin composition for semiconductor encapsulation using the same.

[0002]

2. Description of the Related Art Conventionally, a semiconductor device is typified by an integrated circuit (IC) device in which a large number of transistors and wiring patterns are formed on a silicon substrate, and mechanical, thermal and electrical shocks and changes in atmosphere are caused. Is very sensitive to
It has the drawback of being easily damaged. In order to solve this, a semiconductor element is encapsulated with an encapsulant composed of a resin composition containing a resin such as an epoxy resin and a filler such as fused silica.

[0003]

In recent years, the degree of integration of semiconductor devices has improved, and due to the miniaturization of wiring patterns and the increase in the area of each device, the device has become more powerful than external devices. It is susceptible to physical, thermal, electrical or chemical stimuli and is prone to damage. Therefore, research on improving the resins and fillers used has been actively carried out. For example, regarding fillers, high thermal conductivity of silicon nitride, aluminum nitride, aluminum oxide, etc. in place of or together with fused silica The use of ceramics has been studied (Japanese Patent Laid-Open No. 61-91243).

However, since the thermal expansion coefficient of high thermal conductive ceramics is larger than that of fused silica by an order of magnitude, the thermal expansion coefficient of the encapsulant using the same is larger than that of the semiconductor element and thermal stress is generated. However, there is a problem that the sealing material is cracked or, in an extreme case, the element is broken, and the desired improvement cannot be achieved.

[0005]

Means for Solving the Problems The present invention is intended to solve the above problems, and the gist thereof is that the chemical composition is represented by the composition formula SiO _{2 (1-x)} N _{(4/3) x} (however, 0.003 ≦ x ≦ 0.7
5) A filler containing nitrogen-containing silica glass particles as a main component, and an epoxy resin, a curing agent for the epoxy resin, and a semiconductor encapsulation containing the above filler. It is a resin composition for use.

The present invention will be described in more detail below.

The nitrogen-containing silica according to the present invention needs to be glassy, and if it is crystalline, the coefficient of thermal expansion becomes large and a large thermal stress is generated in the sealing material. Here, "glassy" means that no diffraction line is observed by X-ray diffraction analysis.

The chemical composition of the nitrogen-containing silica glass according to the present invention is represented by the composition formula SiO _{2 (1-x)} N _{(4/3) x} (however, _0.000).
3 ≦ x ≦ 0.75). Where x <0.00
3 has no effect of improving the thermal conductivity, and x> 0.75
If so, crystalline silicon oxynitride (Si ₂ ON ₂ ) and silicon nitride are contained, and the effect of suppressing thermal stress is lost.

The maximum particle size of the filler containing nitrogen-containing silica glass particles of the present invention as a main component is 1 mm or less, preferably 0.1 mm or less. In particular, in the case of a filler for a resin composition for semiconductor encapsulation, the smaller the particle size, the less the damage or damage to the wiring on the element surface, the passivation film, the bonding wire, etc. during molding. However, in consideration of gate clogging during transfer molding, the maximum particle size is preferably 500 μm or less, preferably 149 μm or less, and particularly 74 μm or less.

The filling material of the present invention comprises an active silicon oxide such as porous silicon oxide, etc.
It can be obtained by producing a nitrogen-containing silica glass by heat-treating it at a temperature of ˜1500 ° C., crushing it and then adjusting the particle size.

The content of the filler of the present invention in the resin composition varies depending on the type and application of the resin, but in the case of the resin composition for semiconductor encapsulation, 20 to 97% by volume, preferably 4
It is 0 to 90% by volume. When the content of the filler is less than 20% by volume, the moldability of the resin composition is excellent, but the thermal stress becomes large and the heat shock resistance and moisture resistance reliability deteriorate. on the other hand,
When it exceeds 97% by volume, the moldability of the resin composition is impaired,
Unfilled parts and voids are generated, and electrical insulation and reliability are impaired.

As the resin in which the filler of the present invention is used, bisphenol type epoxy resin, phenol novolac type epoxy resin, alicyclic type epoxy resin, heterocyclic type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin. Epoxy resin such as halogenated epoxy resin, polybenzimidazole, polybenzoxazole, polybenzthiazole, polyoxadiazole, polypyrazole, polyquinoxaline, polyquinazolinedione, polybenzoxazinone, polyindolone, polyquinazolone, polyindoxyl, Silicone resin, silicone-epoxy resin, phenol resin, melamine resin, urea resin, unsaturated polyester, polyamino bismaleimide, diallyl phthalate resin, fluororesin, TPX resin (methyl Pentene polymer (trade name of Mitsui Petrochemical Co., Ltd.)), polyimide, polyamideimide, polyetherimide, polyamide such as 66-nylon and MXD-nylon, amorphous nylon, polyester such as polybutylene terephthalate and polyethylene terephthalate, polyphenylene sulfide, modified Polyphenylene ether, polyarylate, wholly aromatic polyester,
Polysulfone, liquid crystal polymer, polyether ether ketone, polyether sulfone, polycarbonate, maleimide modified resin, ABS resin, AAS (acrylonitrile
Examples thereof include acrylic rubber / styrene) resin and AES (acrylonitrile-ethylene / propylene / diene rubber-styrene) resin.

Of these, an epoxy resin is preferable as the resin of the resin composition for semiconductor encapsulation, and in order to improve the adhesive strength with metal and bending strength at higher temperatures, Kelimide (Mitsui Polyamino bismaleimide-based resins such as Petrochemical's trade name) and BT resin (Mitsubishi Gas Chemical's trade name) are preferable.

Examples of the curing agent for epoxy resin include phenol type curing agents such as phenol novolac and cresol novolac, and acid anhydride type curing agents such as tetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride. I can give you. The amount used is preferably 30 to 90 parts by weight with respect to 100 parts by weight of the epoxy resin.

The resin composition using the filler of the present invention should further contain a rubber component such as butyl rubber, acrylic rubber, ethylene propylene rubber, silicone rubber, polyester elastomer and polybutadiene in order to enhance the thermal shock resistance. You can

Further, if necessary, the following curing accelerator, catalyst, vulcanizing agent, lubricant / release agent, stabilizer, light stabilizer,
A colorant, a flame retardant, a coupling agent and the like can also be added.

As the curing accelerator, benzoguanamine,
2,4-dihydrazino-6-methylamino-S-triazine, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-
Imidazole derivatives such as methylimidazole, various amine complexes of boron fluoride, tertiary amine compounds such as trisdimethylaminomethylphenol, 1,8-diaza-bicyclo (5,4,0) -undecene-7, benzyldimethylamine , Dicyandiamide, bisphenol type epoxy resin or cresol novolac type epoxy resin and amino alcohol compound obtained by reaction with ammonia, nitrogen-containing curing accelerator such as adipic acid hydrazide, triphenylphosphine, tricyclohexylphosphine, methyldiphenylphosphine, tritolyl Examples thereof include organic phosphine-based curing accelerators such as phosphine, 1,2-bis (diphenylphosphino) ethane, and bis (diphenylphosphino) methane.

Examples of the catalyst include bis- (tributyltin) oxide, tin dioctenoate, antimony octoate, tin butyrate, lead monoxide, lead sulfide, lead carbonate, and other curing catalysts, and platinum compound and other polymerization catalysts. You can

Examples of the vulcanizing agent include benzoyl peroxide and dicumyl peroxide.

Examples of the lubricant / release agent include carnauba wax, montana wax, polyester oligomer, silicone oil, low molecular weight polyethylene, paraffin, metal salt of straight chain fatty acid, acid amide, ester and the like.

Examples of stabilizers are 2,6-di-t-butyl-4-methylphenol, 1,3,5-tris (2-methyl-4-hydroxy-5-t-butylphenol) butane, and distearylthio. Examples thereof include dipropionate, trinonylphenyl phosphite, tridecyl phosphite and the like.

As the light stabilizer, 2,2'-dihydroxy-4-methoxybenzophenone, 2 (2'-hydroxy-5-methylphenyl) benzotriazole, 4-
Examples thereof include t-butylphenyl salicylate and ethyl-2-cyano-3,3-diphenylacrylate.

Examples of the colorant include red iron oxide, carbon black and the like.

As the flame retardant, antimony trioxide, antimony tetraoxide, triphenylstibine, hydrated alumina,
Examples thereof include ferrocene, phosphazene, hexabromobenzene, tetrabromophthalic anhydride, tricresyl phosphate, tetrabromobisphenol A, and brominated epoxy derivative.

Regarding coupling, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, N-
Silane-based coupling agents such as β- (aminoethyl) -γ-aminopropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane,
Titanium-based coupling agents such as isopropyltriinstearoyl titanate, dicumylphenyloxyacetate titanate, bis (dioctylpyrophosphate) oxyacetate titanate, isopropyltridecylbenzenesulfonyl titanate, and aluminum-based coupling agents such as acetoalkoxyaluminum diisopropylate. Etc. can be given.

The resin composition containing the filler of the present invention is
After thoroughly mixing the predetermined amounts of the above components with a Henschel mixer or the like, a roll, a Banbury mixer, a kneader,
It can be produced by heating and kneading with a known kneading means such as a ladle machine, an ajihomomixer, a twin screw extruder, a single screw extruder.

[0027]

EXAMPLES The present invention will be described more specifically with reference to Examples, Comparative Examples and Reference Examples.

Examples 1 to 4 Comparative Examples 1 to 2 A mixture of water and ethanol was added dropwise to a commercially available tetraethoxysilane solution, stirred, and then allowed to stand at a temperature of 35 ° C. for 10 hours, and then gradually heated to 80 ° C. over 2 days. The temperature was raised to 1, and a wet gel body of silicon oxide was manufactured. Then, it was gradually heated from room temperature to a temperature of 150 ° C. in a vacuum for 2 days, and further heated and held at that temperature for 2 days to obtain a porous silicon oxide composed of a silica gel body. It was heated to the temperature shown in Table 1 in a nitrogen atmosphere, and while keeping the temperature, ammonia gas was introduced and held for the time shown in Table 1. Then, it was cooled to room temperature under a nitrogen atmosphere.

The chemical analysis of the obtained material is carried out by ICP (high frequency plasma emission spectroscopic analysis) method for silicon and oxygen / nitrogen simultaneous analyzer (trade name "TC-136" manufactured by LECO) for oxygen and nitrogen. Then, the x value in the composition formula SiO _{2 (1-x)} N _{(4/3) x} shown in Table 1 was determined from the results.

In X-ray diffraction analysis, no diffraction lines were found in Examples 1 to 4 and Comparative Example 1, but in Comparative Example 2, diffraction lines of Si ₃ N ₄ and Si ₂ ON ₂ were found. It was
The maximum particle size is 74 μm, and the average particle size is 20 μm.
The particle size was adjusted to obtain a filler.

An ortho-cresol novolac type epoxy resin: a brominated cresol novolac type epoxy resin having a weight ratio of 100: 30 was added to 100 parts by weight of a main agent, and 50 parts by weight of a phenol novolac resin as a curing agent. A compound was prepared by mixing the materials so as to contain 70% by volume.

The above compound was subjected to low-pressure transfer molding using a small transfer molding machine, and the thermal conductivity of the molded body was measured by a steady-state thermal conductivity measuring device. The results are shown in Table 1.

Then, using the above compound, 10 molded products were manufactured by sealing the aluminum lead frame and the silicon element by low-pressure transfer molding.
Repeated rapid cooling and rapid heating at 200 ℃ -200 ℃, 1
The number of cycles in which cracks occurred in 5 or more out of 0 molded articles was measured to evaluate the thermal stress property. The results are shown in Table 1.
Shown in.

Reference Examples 1 to 4 Instead of the filler of the present invention, fused silica powder having an average particle size of about 10 μm (Reference Example 1), silicon nitride powder (Reference Example 2), silicon oxynitride (Si ₂ ON ₂ ) Powder (reference example 3)
And the same test was performed using aluminum nitride powder (Reference Example 4). The results are shown in Table 1.

[0035]

[0036]

The resin composition using the filler of the present invention is
Since it has high thermal conductivity and low thermal stress, it has a great effect of reducing damage to the semiconductor element, which greatly contributes to improvement of semiconductor productivity.

Claims (2)

[Claims] 1. A chemical composition is a composition formula SiO _{2 (1-x)} N _{(4/3) x.}
A filler containing nitrogen-containing silica glass particles represented by (where 0.003 ≦ x ≦ 0.75) as a main component. 2. A resin composition for semiconductor encapsulation, which comprises an epoxy resin, a curing agent for the epoxy resin, and the filler according to claim 1.