JP3143220B2 - Filler and resin composition for semiconductor encapsulation using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

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

[0002]

2. Description of the Related Art Conventionally, a semiconductor device has been subjected to mechanical, thermal, electric shock, or atmospheric change, as represented by an integrated circuit (IC) device having a large number of transistors and wiring patterns formed on a silicon substrate. Very sensitive to
There is a disadvantage that it is easily damaged. In order to solve this, a semiconductor element is sealed with a sealing material made 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 been further improved, and due to the miniaturization of wiring patterns and the increase in the area per device, etc., devices have become more external than conventional devices. Sensitive to thermal, electrical, electrical or chemical stimuli and easily damaged. Therefore, research on the improvement of resins and fillers to be used is being actively conducted. For example, regarding fillers, high thermal conductivity such as silicon nitride, aluminum nitride, aluminum oxide, etc., instead of or together with fused silica, is used. Use of ceramics has been studied (Japanese Patent Application Laid-Open No. 61-91243).

However, since the thermal expansion of high thermal conductive ceramics is about one order of magnitude higher than that of fused silica, the thermal expansion coefficient of the encapsulant using the same is higher than that of semiconductor elements, and thermal stress is generated. However, there has been a problem that cracks are generated in the sealing material or, in an extreme case, the element is broken, and the improvement is not as expected.

[0005]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above problems, and the gist of the invention is that the chemical composition is represented by a composition formula of SiO _{2 (1-x)} N _{(4/3) x} (where, 0.003 ≦ x ≦ 0.4
9 ) A filler comprising nitrogen-containing silica glass particles represented by the following as a main component, an epoxy resin, a curing agent for the epoxy resin, and a semiconductor encapsulation comprising the filler. It is a resin composition for use.

Hereinafter, the present invention will be described in more detail.

[0007] The nitrogen-containing silica according to the present invention must be glassy, and if it is crystalline, the coefficient of thermal expansion is large and a large thermal stress is generated in the sealing material. Here, "vitreous" 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 a composition formula SiO _{2 (1-x)} N _{(4/3) x} (where 0.00
3 ≦ x ≦ 0.49 ). Where x <0.00
In No. 3, there is no effect of improving the thermal conductivity, and x> 0.49
In this case, crystalline silicon oxynitride (Si ₂ ON ₂ ) and silicon nitride are contained, and the effect of suppressing large thermal stress is lost.

The maximum particle size of the filler containing the 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 of a resin composition for semiconductor encapsulation, the smaller the particle size, the less damage or damage to wiring, passivation film, bonding wires, etc. on the element surface during molding is reduced. However, in consideration of gate clogging during transfer molding, the maximum particle size is preferably 500 μm or less, more preferably 149 μm or less, and particularly preferably 74 μm or less.

[0010] The filler of the present invention is prepared by adding an active silicon oxide such as porous silicon oxide under an ammonia atmosphere to a concentration of 500.
It can be obtained by producing a nitrogen-containing silica glass by heat treatment at a temperature of １1500 ° C., and adjusting the particle size after grinding.

The content of the filler of the present invention in the resin composition varies depending on the type and use of the resin. In the case of a resin composition for encapsulating a semiconductor, the content is preferably 20 to 97% by volume, preferably 4%.
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 increases, and the heat shock resistance and the humidity resistance decrease. on the other hand,
If it exceeds 97% by volume, the moldability of the resin composition is impaired,
Unfilled portions and voids are generated, and electrical insulation and reliability are impaired.

The resin in which the filler of the present invention is used includes bisphenol type epoxy resin, phenol novolak type epoxy resin, alicyclic type epoxy resin, heterocyclic type epoxy resin, glycidyl ester type epoxy resin, glycidylamine type epoxy resin , Epoxy resins such as halogenated epoxy resins, polybenzimidazole, polybenzoxazole, polybenzthiazole, polyoxadiazole, polypyrazole, polyquinoxaline, polyquinazolinedione, polybenzoxazinone, polyindrone, polyquinazolone, polyindoxyl, Silicon resin, silicon-epoxy resin, phenol resin, melamine resin, urea resin, unsaturated polyester, polyaminobismaleimide, diallyl phthalate resin, fluororesin, TPX resin (methyl Penten polymer (trade name of Mitsui Petrochemical Co., Ltd.), polyimide, polyamide imide, polyether imide, 66-nylon, MXD-nylon, polyamide such as amorphous nylon, polyester such as polybutylene terephthalate and polyethylene terephthalate, polyphenylene sulfide, modified Polyphenylene ether, polyarylate, wholly aromatic polyester,
Polysulfone, liquid crystal polymer, polyetheretherketone, polyethersulfone, polycarbonate, maleimide-modified resin, ABS resin, AAS (acrylonitrile
Acrylic rubber / styrene resin and AES (acrylonitrile-ethylene-propylene-diene rubber-styrene) resin.

Of these, epoxy resin is preferable as the resin of the resin composition for encapsulating a semiconductor, and kerimide (Mitsui Mitsui) is used in order to improve the bonding strength with metals and the bending strength at higher temperatures. Polyaminobismaleimide-based resins such as Petrochemical Co., Ltd.) and BT resin (Mitsubishi Gas Chemical Co., Ltd.) are preferred.

Examples of the epoxy resin curing agent include phenolic curing agents such as phenol novolak and cresol novolak, and acid anhydride curing agents such as tetrahydrophthalic anhydride, hexahydrophthalic anhydride and methylhexahydrophthalic anhydride. I can give it. The amount used is preferably 30 to 90 parts by weight based on 100 parts by weight of the epoxy resin.

The resin composition using the filler of the present invention further contains rubber components such as butyl rubber, acrylic rubber, ethylene propylene rubber, silicone rubber, polyester elastomer, and polybutadiene in order to enhance thermal shock resistance. Can be.

Further, if necessary, the following curing accelerators, catalysts, vulcanizing agents, lubricants / release agents, stabilizers, light stabilizers,
A coloring agent, a flame retardant, a coupling agent, and the like can be added.

Benzoguanamine, as a curing accelerator,
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-diazabicyclo (5,4,0) -undecene-7, benzyldimethylamine , Dicyandiamide, amino alcohol compounds obtained by reaction of bisphenol type epoxy resin or cresol novolak type epoxy resin with ammonia, nitrogen-containing curing accelerators such as adipic hydrazide, triphenylphosphine, tricyclohexylphosphine, methyldiphenylphosphine, tolyl Organic phosphine-based hardening accelerators such as phosphine, 1,2-bis (diphenylphosphino) ethane, and bis (diphenylphosphino) methane can be given.

Examples of the catalyst include curing catalysts such as bis- (tributyltin) oxide, tin dioctenoate, antimony octoate, tin butyrate, lead monoxide, lead sulfide and lead carbonate, and polymerization catalysts such as platinum compounds. Can be.

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

Examples of the lubricant and release agent include carnauba wax, montana wax, polyester oligomer, silicone oil, low molecular weight polyethylene, paraffin, metal salts of linear fatty acids, acid amides and esters.

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

Light stabilizers include 2,2'-dihydroxy-4-methoxybenzophenone, 2 (2'-hydroxy-5-methylphenyl) benzotriazole,
Examples include t-butylphenyl salicylate, ethyl-2-cyano-3,3-diphenylacrylate and the like.

Examples of the colorant include bengara, carbon black and the like.

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

For coupling, vinyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, N-
silane coupling agents such as β- (aminoethyl) -γ-aminopropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane,
Titanium-based coupling agents such as isopropyltriinstearoyl titanate, dicumylphenyloxyacetate titanate, bis (dioctylpyrophosphate) oxyacetate titanate, and 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 comprises:
After sufficiently mixing a predetermined amount of each of the above components with a Henschel mixer or the like, a roll, a Banbury mixer, a kneader,
It can be manufactured by heating and kneading by a known kneading means such as a grinder, an azimohomomixer, a twin-screw extruder, and a single-screw extruder.

[0027]

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

Examples 1-4 Comparative Examples 1-2 A mixture of water and ethanol was dropped into a commercially available tetraethoxysilane solution, and the mixture was stirred and allowed to stand at a temperature of 35 ° C. for 10 hours. To produce a wet gel of silicon oxide. Thereafter, it was gradually heated and heated from room temperature to a temperature of 150 ° C. in vacuum over 2 days, and further kept at that temperature for 2 days and dried to obtain a porous silicon oxide made of silica gel. It was heated to a temperature shown in Table 1 in a nitrogen atmosphere, and kept at that temperature for a time shown in Table 1 after introducing ammonia gas. Then, it was cooled to room temperature under a nitrogen atmosphere.

Chemical analysis of the obtained material was performed by ICP (high frequency plasma emission spectroscopy) for silicon, and a simultaneous oxygen / nitrogen analyzer (trade name “TC-136” manufactured by LECO) for oxygen and nitrogen. 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 observed 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 observed. Was.
These products were obtained by converting the maximum particle size to 74 μm and the average particle size to 20 μm.
The particle size was adjusted to obtain a filler.

A weight ratio of ortho-cresol novolak type epoxy resin: brominated cresol novolak type epoxy resin of 100: 30 is mixed with 100 parts by weight of the main ingredient, 50 parts by weight of phenol novolak resin as a curing agent, and The materials were mixed to contain 70% by volume to produce a compound.

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

Next, by using the above-mentioned compound, ten molded bodies in which the aluminum lead frame and the silicon element were sealed by low-pressure transfer molding were produced.
Repeat rapid cooling and rapid heating at 200 ° C to 200 ° C,
The number of cycles in which cracks occurred in 5 or more of the 0 compacts was measured, and the thermal stress property was evaluated. Table 1 shows the results.
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)
A similar test was performed using the aluminum nitride powder and aluminum nitride powder (Reference Example 4). Table 1 shows the results.

[0035]

[0036]

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

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08K 3/00-13/08 C08L 1/00-101/16 H01L 23/30 CA (STN)

Claims (2)

(57) [Claims] The chemical composition is represented by a composition formula SiO _{2 (1-x)} N _{(4/3) x}
(However, a filler characterized by comprising nitrogen-containing silica glass particles represented by the formula : 0.003 ≦ x ≦ 0.49 ) as a main component. 2. A resin composition for encapsulating a semiconductor, comprising an epoxy resin, a curing agent for the epoxy resin, and the filler according to claim 1.