JPH0653787B2 - Resin-sealed semiconductor device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin-encapsulated semiconductor device capable of highly reliable operation.

[Background of the Invention]

Conventionally, a resin-encapsulated semiconductor device is left at a high temperature or in a high-temperature and high-humidity state (65 to 85 ° C., 95% relative humidity, 121 ° C., 2 atmospheric pressure supersaturated steam) as compared with a ceramics-encapsulated semiconductor device. ) Was inferior in terms of operational reliability.

In a resin-sealed semiconductor device, a gap is created between the resin and the lead wire or a gap between the resin and the semiconductor element,
Water enters from the outside through the gap, and Al on the element
This is because the wiring and bonding pad parts are easily corroded and broken.

Therefore, as measures against this, there have been proposed a method of increasing the adhesiveness with a resin by treating the element surface with a coupling agent, a method of sealing with a resin composition containing a coupling agent, and the like.

However, even with these methods, the moisture resistance of the resin-encapsulated semiconductor device has not been sufficiently improved.

Further, in memory LSIs and the like, the trend toward higher density and higher integration has been remarkable, and the charge capacity of one cell has become smaller and smaller. Therefore, the α-ray energy generated from uranium and thorium contained in a small amount in the package material (for example, the filler in the encapsulating resin composition) causes a defect in the operation of adjusting the charge capacity in the cell (soft Error) There is a problem.

As a countermeasure against this, a high-purity α-ray shielding material (for example, polyimide) is provided between the semiconductor element and the lead wire and the sealing material. However, the α-ray shield material is inferior in adhesiveness and adhesiveness to the semiconductor element, and has not always been effective in preventing corrosion of the Al wiring described above.

[Object of the Invention]

An object of the present invention is to provide a resin-encapsulated semiconductor device that can operate with high reliability even when left at high temperature or under high temperature and high humidity.

[Outline of Invention]

Briefly describing the present invention, the present invention relates to a resin-encapsulated semiconductor device, in which at least a part of a semiconductor element is
The following general formula I: A resin composition containing a polyfunctional epoxy compound represented by the formula (m is 0, 1 or 2), an N, N′-substituted bismaleimide compound, and an inorganic filler, and / or Alternatively, it is characterized by being sealed.

Examples of the compound that can be used in combination with the polyfunctional epoxy compound represented by the above formula I in the resin composition include novolak type phenol resin, poly-p-hydroxystyrene, and the following general formula II: Glycerin tris (trimellitate) represented by the following general formula III: A mixture of a trimer and a tetramer of phenoxyphosphazene represented by the formula (wherein R represents hydrogen or bromine), a nitrogen-containing fluorocarbon polymer, an isocyanate compound having a uretdione ring, a maleimide compound, a curing agent. , And at least one component selected from the group consisting of rubber components having functional groups capable of reacting with epoxy groups.

Further, as an example of the semiconductor device of the present invention, there is one in which a semiconductor element and a lead wire are covered with the resin composition and sealed with a resin composition containing an inorganic filler.

In the present invention, the tris (hydroxyphenyl) methane-based polyfunctional epoxy compound represented by the general formula I is obtained by the process described in US Pat. No. 4,394,496, Chemical (Dow Chemic
al) company, and it is marketed under the brand name of XD-9053.

In the present invention, the glycerin tris (compound containing trimellitate as a main component is represented by the general formula II, from Shin Nihon Rika Co., Ltd., Lycarezin TMTA (softening point 65 to 85 ° C.)
A polyfunctional carboxylic acid anhydride mainly composed of a compound marketed under the trade name of 50% by weight or less Product name: Rika Resin TMEG (manufactured by Shin Nippon Rika) or It is possible to include the product name: Licaregin ETA-37 (manufactured by Shin Nippon Rika Co., Ltd.) within a range that does not impair the effects of the present invention. Also, maleic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride,
It can also be used in combination with a known carboxylic acid compound such as benzophenone tetracarboxylic acid anhydride or p-phenyl tetracarboxylic acid anhydride.

Further, in the present invention, as the 3- to 4-mer of phenoxyphosphazene represented by the general formula III, phenoxyphosphazene (such as P-3800 manufactured by Shin Nisso Kako Co., Ltd.) and p-promophoenoki Syphosphazene (Shin-Nisso Kako B-380
0) etc. In addition to these, the general formula: A polytolufluoroethoxyphosphazene represented by the formula (n is a positive integer) can also be used in combination.

Further, in the present invention, a nitrogen-containing fluoropolymer may be added and used. Examples of nitrogen-containing fluorocarbon polymers include the following (where p
And q are integers).

Further, in the present invention, as the isocyanate compound having a uretdione ring, for example, there is one represented by the following formula.

n is an integer, R ', R ": an aliphatic, aromatic or alicyclic divalent hydrocarbon group, and an aromatic hydrocarbon group is useful as R', R".

Examples of such compounds include 1,3-bis (3-isocyanato-o-tolyl) -2,4-uretidinedione and 1,3-bis (3-isocyanato-p-tolyl).
-2,4-uretidinedione, 1,3-bis (3-isocyanato-4-methoxyphenyl) -2,4-uretidinedione, 1,3-bis [4- (4-isocyanatophenylmethyl) phenyl] -2,4-uretidinedione and the like.

A mixture of a diisocyanate having a uretdione ring, a compound and an epoxy compound, at high temperature, forms an isocyanurate ring and an oxazolidone ring, in which butadiene-based polymer, rubber particles such as a siloxane polymer are dispersed. When present, a cured product having excellent heat resistance and a low elastic modulus is produced.

In the present invention, as for the mixing ratio of the diisocyanate compound having a uretdione ring and the epoxy compound, the total amount of the isocyanate groups including the isocyanate group generated by thermal dissociation of the uretdione ring is 1 mol of the epoxy group of the epoxy compound. The ratio is preferably 0.6 to 10.0 mol.

In the present invention, examples of the N, N'-substituted bismaleimide compound include N, N'-ethylenedimaleimide, N, N'-ethylenedimaleimide,
N'-ethylenebis [2-methylmaleimide], N,
N'-trimethylenedimaleimide, N, N'-tetramethylenedimaleimide, N, N'-hexamethylenedimaleimide, N, N'-hexamethylenebis [2-methylmaleimide], N, N'-dodecamethylene Dimaleimide,
N, N'-m-phenylene dimaleimide, N, N'-p-
Phenylene dimaleimide, N, N '-(oxy-p-phenylene) dimaleimide, N, N'-(methylene-di-
p-phenylene) dimaleimide, N, N '-(methylene-di-p-phenylene) bis [2-methylmaleimide], N, N'-2,4-tolylenedimaleimide, N,
N'-2,6-tolylene dimaleimide, N, N'-m-xylylene dimaleimide, N, N'-p-xylylene dimaleimide, N, N'-oxypropylene dimaleimide,
There are N, N'-ethylenebis (oxypropylenemaleimide), N, N'-oxydiethylenedimaleimide, and at least one of them is used.

Further, the butadiene-based polymer in the present invention includes 1,2-polybutadiene having a molecular weight of about 300 to 10,000, 1,4-polybutadiene, a butadiene-styrene copolymer and a butadiene-acrylonitrile copolymer, and further a terminal. Examples of the reactive group include a carboxyl group, a hydroxyl group, a polymer thereof having an amino group and a vinyl group, and the like. These are Nippon Soda,
It is commercially available from companies such as Ube Industries and Mitsui Polychemical.

The encapsulating resin composition of the present invention includes a conventionally known epoxy resin, for example, diglycidyl ether of bisphenol A,
Butadiene diepoxide, 3,4-epoxycyclohexylmethyl- (3,4-epoxy) cyclohexanecarboxylate, vinylcyclohexane dioxide, 4,
4'-di (1,2-epoxyethyl) diphenyl ether, 4,4 '-(1,2-epoxyethyl) biphenyl,
2,2-bis (3,4-epoxycycloxyl) propane, resorcin glycidyl ether, phloroglucin diglycidyl ether, methyl phloroglucin diglycidyl ether, bis- (2,3'-epoxycyclopentyl) ether, 2 -(3,4-Epoxy) cyclohexane-5,5-spiro (3,4-epoxy) -cyclohexane-m-dioxane, bis- (3,4-epoxy-6-methylcyclohexyl) adibate, N, N'-
Bifunctional epoxy compounds such as m-phenylene bis (4,5-epoxy-1,2-cyclohexane) dicarboximide, triaminoglycol ether of paraaminophenol, polyallylglycidyl ether, 1,3,5-tri (1, 2-epoxyethyl) benzene, 2,2 ', 4,4'
-Trifunctional or higher functional epoxy compounds such as tetraglycidoxy benzophenone, phenol formaldehyde novolac polyglycidyl ether, glycerin triglycidyl ether, and trimethylolpropane triglycidyl ether are used.

One or more of the above compounds may be used in combination depending on the application and purpose. A curing agent is used in combination with these epoxy resins. Hiroshi Kakiuchi: Epoxy Resins (September, 1970, published by Shokoido) pages 109-149, Lee, Neville: Epoxy Resins, New York City, Matsuglow Hill.
Book Company, Inc. (Mc Graw-
Hill Book Company Inc) (issued in 1957) No. 63-
Page 141, PE Brunis: Epoxy Resins Technology, Interscience Science, New York, Inp.
terscience Pubblishers) (issued in 1968) No. 45-
Compounds described on page 111, such as aliphatic polyamines, aromatic polyamines, amines including secondary and tertiary amines, carboxylic acids, carboxylic anhydrides, aliphatic and aromatic polyamide oligomers and polymers , Boron trifluoride-amine complex, synthetic resin initial condensate such as phenol resin, melamine resin, urea resin, urethane resin, etc., as well as dicyandiamide, galbonic acid hydrazide, polyamine nomaleimides and the like.

One or more of the above-mentioned curing agents can be used depending on the application and purpose.

In particular, a phenol novolac resin is suitable as a curing agent component of the above-mentioned semiconductor encapsulating material from the viewpoints of adhesion of the cured resin to the metal insert, workability during molding and the like.

In the resin composition, a known catalyst known to have an effect of promoting the curing reaction between the epoxy compound and the novolak type phenol resin can be used.

Examples of such a catalyst include triethanolamine,
Tertiary amines such as tetramethylbutanediamine, tetramethylpentanediamine, tetramethylhexanediamine, triethylenediamine and dimethylaniline; oxyalkylamines such as dimethylaminoethanol and dimethylaminopentanol; and tris (dimethylaminomethylphenol, N- There are amines such as methylmorpholine and N-ethylmorpholine.

Also, cetyl trimethyl ammonium bromide, cetyl trimethyl ammonium chloride, dodecyl trimethyl ammonium iodide, trimethyl dodecyl ammonium chloride, penzyl dimethyl tetradecyl ammonium chloride, penzyl methyl palmityl ammonium chloride, allyl decyl trimethyl ammonium bromide, benzyl dimethyl stearyl ammonium bromide. , Stearyl trimethyl ammonium chloride, benzyl dimethyl tetradecyl ammonium acetate, and other quaternary ammonium salts.

In addition, 2-ethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-methyl-4-ethylimidazole, 1-butylimidazole,
1-propyl-2-ethylimidazole, 1-benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-azine 2-methylimidazole, imidazoles such as 1-azine-2-undecylimidazole, triphenylphosphine tetraphenylborate,
Tetraphenylphosphonium tetraphenylborate,
Tetraethylboron salts such as triethylamine tetraphenylborate, N-methylmorpholine tetophenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, 2-ethyl-1,4-dimethylimidazole tetraphenylborate, etc. is there.

In the present invention, the resin composition, depending on the purpose and use,
Various inorganic substances and additives can be mixed and used. Specific examples thereof include zircon, silica, fused silica glass, alumina, aluminum hydroxide, glass,
Quartz glass, calcium silicate, gypsum, calcium carbonate, magnesite, clay, kaolin, talc, iron powder,
Copper powder, mica, asbestos, silicon carbide, boron nitride,
Fillers such as molybdenum disulfide, lead compounds, lead oxides, white zinc, titanium white, carbon black, mold release agents such as higher fatty acids and waxes, epoxysilanes,
Coupling agents such as vinylsilane, aminosilane, porane-based compounds, alkoxy titanate-based compounds, and aluminum chelate compounds. In addition, antimony,
A known flame retardant containing a phosphorus compound, bromine or chlorine can be used.

Example of Invention

Hereinafter, the present invention will be described in more detail with reference to Examples.
The present invention is not limited to these examples.

In each of the following examples, Example numbers 4 and 9 are examples of the present invention, and other numbers, that is, 1 to 3, 5 to 8,
And 10 to 13 are shown as reference examples of the present invention.

Examples 1 to 13 Tris (hydroxyphenyl) which is an essential component of the present invention
As a polyfunctional epoxy compound based on methane, X
D-9053 (Dow Chemical Co., epoxy equivalent, 2
(20, softening point, 85 ° C.) was used to prepare 13 kinds of compounded compositions in which various materials shown in Table 1 below were compounded in predetermined amounts.

Next, the compounded composition was kneaded at 75 to 85 ° C. for 10 minutes by a two-roll roll having a diameter of 8 inches, then cooled and coarsely pulverized to prepare a resin composition for semiconductor encapsulation.

Next, a 256 kbit D.RAM (Dynamic Random Access Memory) LSI is placed at 175 to 180 ° C.
5 minutes, under 70kg / cm ² condition, transfer molding,
The semiconductor device of the present invention was obtained.

Under the same molding conditions, a disk having a diameter of 90 mm and a thickness of 2 mm was molded, and a TMA measurement sample was prepared from the disk.

Table 1 shows the glass transition point of the cured product and resin-encapsulated LS.
Each I (50 pieces) was left in 121 ° C., 2 atmosphere supersaturated steam (PCT), and after a predetermined time, taken out from the kettle.
The results of checking the disconnection failure due to the corrosion of the Al wiring on the LSI element by the presence or absence of electrical operation are shown.

In Table 1, the epoxy resin is XD-9053 manufactured by Dow Chemical Co., the novolak type epoxy resin is ESCN-195 manufactured by Sumitomo Chemical Co., Ltd., and the novolak type phenol resin is EPPN-201 manufactured by Nippon Kayaku Co., Ltd. Is TMTA manufactured by Shin Nippon Rika Co., Ltd., Phenoxyphosphazene is P-3800 manufactured by Shin Nisso Chemical Co., TDI-dimer is DTT manufactured by Sumitomo Bayer, and polybutadiene rubber is a carboxyl group-terminated polybutadiene C manufactured by Ube Industries.
TBM × 1300, nitrogen-containing fluorocarbon polymer is a synthetic product, poly-p-hydroxystyrene is M resin manufactured by Maruzen Petroleum Co., triethylamine tetraphenylborate is TPP-K manufactured by Hokuko Kagaku KK, and triphenylphosphine is Hokuko Kagaku. Made by Shin-Etsu Chemical Co., Ltd.
High-purity products were used for M303 and fused silica glass powder.

As is clear from Table 1, the semiconductor device of the present invention has remarkably improved operational reliability in a high temperature and high humidity state as compared with a semiconductor sealed with a conventional material.

[Effects of the Invention] As described above, the resin-encapsulated semiconductor device of the present invention is excellent in moisture resistance and heat resistance, and accordingly water can be prevented from entering and highly reliable operation is possible. That is a remarkable effect.

Front Page Continuation (72) Inventor Tokuyuki Kaneshiro 4026 Kuji-cho, Hitachi City, Ibaraki Prefecture, Hitachi Research Laboratory, Ltd. (72) Inventor Hidetoshi Abe 4026, Kuji Town, Hitachi City, Ibaraki Hitachi, Ltd., Hitachi Research Laboratory (72) Masanori Segawa 4026 Kuji Town, Hitachi City, Ibaraki Prefecture, Hitachi Research Institute, Ltd. (56) Reference Document JP-A-58-198526 (JP, A) US Patent 4394496 (US, A)

Claims (1)

[Claims] 1. A semiconductor device comprising at least a part of the following general formula I: A resin composition containing a polyfunctional epoxy compound represented by the formula (m is 0, 1 or 2), an N, N′-substituted bismaleimide compound, and an inorganic filler, and / or Alternatively, the resin-encapsulated semiconductor device is characterized by being encapsulated.