JPS62177950A - Semiconductor device - Google Patents

Abstract

PURPOSE:To enhance the reliability of a semiconductor under high temperature and high moisture environment by coating a semiconductor element and lead wirings with a resin composition which contains at least fluoroacrylate resin to strengthen alpha-ray resistance. CONSTITUTION:A semiconductor element and lead wirings are coated with a resin composition which contains at least fluoroacrylate resin. The fluoroacrylate resin includes fluoroacrylate resin represented by the formula I, and fluoromethacrylate resin represented by the formulae II, III, IV. Thus, the alpha-ray resistance is strengthened to enhance the reliability of a semiconductor under high temperature and high moisture environment.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a resin-encapsulated semiconductor device, and the present invention relates to a resin-sealed semiconductor device, which is particularly resistant to alpha rays and capable of highly reliable operation even under high temperature and high humidity conditions. The present invention relates to a sealed semiconductor device.

[Background of the invention]

In memory LSIs and the like, there has been a remarkable trend toward higher density and higher integration, and the charge capacity per cell has become smaller and smaller. For this reason, the charge capacity in the cell is adjusted by α-ray energy generated from trace amounts of uranium (U) and thorium (Th) contained in the sealing material (for example, fission in the sealing resin composition). There is a problem that causes defects (soft errors).

As a countermeasure against this, high-purity α-ray shielding material (for example, a high-purity α-ray shielding material) is used between the semiconductor element and lead wires and the sealing material.

Polyimide, silicone gel, etc.) are used. However, this α-ray blocking material has poor adhesion and adhesion with semiconductor elements, and high moisture absorption and moisture permeability.
Co-location is necessary to prevent corrosion of AQ wiring on the element, which will be described next.

In other words, in a resin-sealed semiconductor device, a gap is created between the resin and the lead wire or at the interface between the resin and the semiconductor element, and moisture infiltrates from the outside through the gap, causing damage to the metal wiring (AQ) on the element. , the pounding pad section, etc.
This is because it corrodes and breaks easily. In particular, the above-described α-ray shielding material conventionally has poor adhesion to the surface of an element, and thus can be a major factor in reducing the moisture resistance reliability of a semiconductor device.

Therefore, as a countermeasure against this problem, treatment of the surface of the element with a coupling agent, addition of a coupling agent into the α-ray shielding resin, etc. have been proposed and partially implemented.

However, conventional methods have limitations in achieving both soft error resistance and moisture resistance reliability in resin-sealed semiconductors. A related device of this type is, for example, Japanese Patent Publication No. 60-21193.

[Purpose of the invention]

An object of the present invention is to provide a resin-sealed semiconductor device that is resistant to alpha rays and can operate with high reliability even under high temperature and high humidity conditions.

[Summary of the invention]

The gist of the present invention is a semiconductor device in which a semiconductor element and lead wires are coated with a resin composition containing at least a fluoroacrylate resin.

The fluoro-acrylate resin that can be used in the present invention includes, for example, a fluoro-acrylate resin represented by the following formula: % CHδ -(-CH2-C+).

萱C00CH2(CF2CF2)AH HaHa ■-f-CH2C+- 萱C00C(CHI+)2CF2CF3I There are fluoro-methagerylate resins and the like.

Further, examples of the heterocyclic polymer that can be used in the present invention include polyimide, polybenzimidazole, polybenzthiazole, polyoxadiazole, polypyrazole,
Examples include polyquinoxaline, polythiazole, polytetraazopyrene, poly-4-phenyl-1,2,4-triazole, polyquinazolinedione, and polybenzoxadisodione. Further, the skeleton of the heterocyclic polymer may contain an amide bond, an ester bond, an ether bond, a sulfide bond, a sulfone bond, a urethane bond, a siloxane bond, or the like.

Among the above-mentioned heterocyclic polymers, polyimide is particularly effective because it has excellent coating properties (filming properties) on devices. In the formula, R represents an organic or inorganic bond.

It also represents or nothing, -〇-. ] Since the polyimide represented by
This is preferable for suppressing corrosion of wiring.

In addition, coupling agents that can be used in the present invention include epoxysilane, aminosilane, mercaptosilane,
Examples include known silane-based coupling agents such as fluorosilane and vinylsilane; known coupling agents such as metal alkoxides such as aluminum, titanium, and zirconium; and chelate-based zircoaluminate-based coupling agents.

Examples of the resin composition for semiconductor encapsulation that can be used in the present invention include epoxy resin, phenol resin, melamine resin, urea resin, diallyl phthalate resin,
Examples include unsaturated polyester resin, urethane resin, addition type polyimide resin, silicone resin, polyparavinylphenol resin, polyamide, polyetheretherketone, and polypropylene.

Among these, epoxy resin compositions are particularly useful as sealing resin compositions.

Examples of the epoxy resin include diglycidyl ether of bisphenol A, butadiene dieboxide, 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-
epoxycyclohexyl) propane, glycidyl ether of resorcinol, diglycidyl ether of phloroglucin, diglycidyl ether of methyl 0 loroglucin, 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)adipate, N.

N'-m-phenylenebis(4,5-epoxy-1,2
-cyclohexane) dicarboximide, triglycidyl ether of para-aminophenol, polyallyl glycidyl ether, 1,3.5-tri(1,2
-epoxyethyl)benzene, 2.2', 4.4'-
Tri- or higher functional epoxy compounds such as tetraglycidoxybenzophenone, polyglycidyl ether of phenol formaldehyde novolac, triglycidyl ether of glycerin, triglycidyl ether of trimethylolpropane, and polyfunctional epoxy compounds based on tris(hydroxyphenyl)methane. , polyglycidyl ether of novolac of bisphenol A and pol-11 aldehyde, and the like.

One or more of the above epoxy compounds can be used in combination depending on the use and purpose. A curing agent is used in combination with these epoxy resins. They are written by Hiroshi Kakiuchi: Eboxy Resin (published September 1970), pages 109-149, L
ee, Navj, ], 1e Author: EpoxyResins
(Mc Graw-Hj, ], l Book Co.
pany Inc. NewWork, 1957) pages 63-141, P, E.

Written by Brunis: Epoxy Re5ins Tech
nology(IntersciencesPublis
hers New York, published in 1968) 45~
Compounds described on page 111 etc. 1 For example, aliphatic polyamines, aromatic polyamines, amines including secondary and tertiary amines, carboxylic acids, carboxylic acid anhydrides including trimellitic acid triglyceride (Recaregi L, TMIA, etc.) aliphatic and aromatic polyamide oligomers and polymers, boron trifluoride-amine complexes, synthetic resin initial condensates such as phenolic resins, melamine resins, urea resins, and urethane resins, others, dicyandimide, carboxylic acid hydrazide , polyaminomaleimides, etc.

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

In particular, Uninorborac resin has been improved in terms of the adhesion of the cured resin to metal inserts and workability during molding.
It is suitable as a curing agent component of the above-mentioned semiconductor encapsulation material.

In the resin composition, a known catalyst known to be effective in accelerating the curing reaction between an epoxy compound and a novolac type phenol resin can be used.

Such catalysts include, for example, triethanolamine,
Tertiary amines such as tetramethylbutanediamine, tetramethylbutanediamine, tetramethylhexanediamine, triethylenediamine, dimethylaniline, oxyalkylamines such as dimethylaminoethanol, dimethylaminopetanol, and tris(dimethylaminomethyl)
There are amines such as phenol, N-methylmorpholine, and N-ethylmorpholine.

Also, cetyltrimethylammonium bromide, cetyltrimethylammonium chloride, dodecyltrimethylammonium iodide, trimethyldodecylammonium chloride, benzyldimethyltetradecylammonium chloride, benzylmethylpalmitylammonium chloride, allyldodecyltrimethylammonium bromide, benzyldimethylstearylammonium bromide, There are quaternary ammonium salts such as stearyltrimethylammonium chloride and benzyldimethyltetradecylammonium acetate.

Also, 2-ethylimidazole, 2-undecylimidazole, 2-heptadecyl imidazole, 2-methyl-
4-ethylimidazole, 1-butylimidazole, 1
-Propyl-2-methylimidazole, 1-benzyl-
2-Methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-azine-2-methylimidazole, 1-azine-2-undecyl Imidazole such as imidazole, triphenylphosphine tetraphenylborate, tetraphenylphosphonium tetraphenylborate, triethylamine tetraphenylborate, N-methylmorpholinetetraphenylborate, 2-ethyl-4-methylimidazole tetraphenylborate, 2-ethyl-1 , 4-dimethylimidazole tetraphenylborate and other tetraphenylboron salts.

In the present invention, various inorganic substances and additives can be added to the resin composition depending on the intended use. Specific examples 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, zinc white, titanium white, carbon black, higher fatty acids, mold release agents such as waxes, epoxysilanes, vinylsilanes, aminosilanes, borane compounds, alkoxy titanates. and coupling agents such as aluminum chelate-1-compounds. Furthermore, known flame retardant agents containing antimony, phosphorus compounds, bromine, and chlorine can be used.

[Embodiments of the invention]

Example] - In a ~4500 mQ Erlenmeyer flask, 2F + OmQ of N
-Methylpyrrolidone was taken, and a predetermined amount of fluoroacrylate resin represented by the following formula 1 formula % was added as shown in Table 1, and dissolved by heating and stirring to create four types of fluoroacrylate resin solutions.Next, To each of these solutions, as a polyimide, an amic acid (imide precursor) of biphenyltetracarboxylic acid and P-phelenediamine or an aluminum chelate coupling agent ALCH-TR (manufactured by Yoken Fine Chemical Co., Ltd.) was added separately. A predetermined amount is added and dissolved to obtain a coating composition.

Next, at 256, on the element and lead a (including wire bonding line) of the bit D-RAM memory LSI,
A solution of the above coating composition was added dropwise.

After that, 1 hour at 100℃, 1 hour at 200℃, 250℃
Heating was continued for 30 minutes at <RTIgt;C,</RTI> to obtain a coating with a thickness of 30-60 um on the device.

Next, the memory LSI element coated with a composition containing at least a fluoroacrylate resin was transfer molded (180°C, 70°C) with the following epoxy resin composition.
kgf/a#, 1.5 minute molding) to obtain a resin-sealed semiconductor device. Moisture resistance reliability was evaluated for each of 100 LSIs.

For comparison, a resin composition containing no fluoroacrylate resin is also listed as a comparative example13) in Table 1.

Table 1: Preparation of epoxy resin composition for sealing As epoxy resin, XD-9053 (tris(hydroxyphenyl)methane type polyfunctional epoxy compound;
Dow Chemical Co., epoxy equivalent, 22o) 100 parts by weight, novolak type phenol resin (manufactured by Hitachi Chemical Co., Ltd., softening point 78-83°C) 55 parts by weight as a curing agent, triphenylphosphine 2 parts by weight as a catalyst, flame retardant As a chemical material,
3.7 parts by weight of addition type polyimide coated red phosphorus, epoxy silane KBM303 (manufactured by Shin-Etsu Chemical Co., Ltd.) as a coupling agent, 480 parts by weight of fused silica glass powder as a filler, and 1 part by weight of calcium stearate as a mold release agent. 2 parts by weight of Hoechst wax E and 2 parts by weight of carbon black (manufactured by Cabot) as a coloring agent were blended. Then,
After heating and kneading for 7 minutes using two 8-inch diameter rolls at 75 to 85°C, the mixture was cooled and coarsely pulverized to prepare an epoxy resin composition for semiconductor encapsulation.

Other Examples Epoxy resin Toshite, XD-9053, 100 parts by weight, poly P-hydroxystyrene (M
Resin, 60 parts by weight from Maruzen Sekiyu Co., Ltd., as a catalyst,
Triethylamine tetraphenylborate (TEA-K
, manufactured by Hokko Chemical Co., Ltd.) 2.5 parts by weight, 2.0 parts by weight of antimony dioxide as a flame retardant, 2.0 parts by weight of addition type imide coated red phosphorus, 2.0 parts by weight of KBM303 as a coupling agent. , fused silica glass powder 480 as a filler
parts by weight, 1 part by weight of calcium stearate and 2 parts by weight of Hoechst wax as a mold release agent, 2 parts by weight of carbon black as a colorant, 10 parts by weight of a fluoro-acrylate resin represented by the following formula 6% as an additive. part was blended.

Next, the mixture was heated and kneaded for 7 minutes using two rolls with an 8-inch diameter at 75 to 85°C, cooled, and coarsely pulverized to prepare a semiconductor encapsulation resin composition.

Next, 256 is a bit D-RAM memory LSI, 1
00 pieces were resin-sealed by transfer molding under the same conditions as Examples 1 to 4.

Even after the obtained resin-sealed semiconductor device was left in saturated steam at 121° C. and 2 atm for 2,500 hours, there were 0% disconnection failures due to corrosion of the AQ wiring.

Claims (1)

[Claims] 1. A semiconductor device characterized in that a semiconductor element and lead wires are coated with a resin composition containing at least a fluoroacrylate resin.