JP2003268205A - Epoxy-based resin composition and semiconductor apparatus using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin composition excellent in crack resistance at a reflow and adhesion, especially adhesion to silver-plating, and having no unpleasant small when manufacturing and using. <P>SOLUTION: The epoxy resin composition comprises a combination of: an epoxy resin (A); a curing agent (B); a filler (C); a silane coupling agent (D); and a deodorant (E), wherein the silane coupling agent (D) contains mercaptosilane as an essential component and the deodorant (E) contains one or more of a eucalyptus oil, 1,8-cineol and propylene oxide. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an epoxy resin composition which is excellent in reliability and has a peculiar unpleasant odor despite the use of mercaptosilane, and is particularly suitable for semiconductor encapsulation. It is a thing.

[0002]

2. Description of the Related Art The characteristics required of epoxy resin compositions for semiconductor encapsulation include reliability and moldability. Reliability includes solder heat resistance, high temperature reliability, heat resistance reliability, and moisture resistance. However, as moldability, fluidity, hot hardness,
Bali and so on.

Recently, the mounting of a semiconductor device package on a printed circuit board has been increased in density and automation. Instead of the conventional "insertion mounting method" in which lead pins are inserted into holes in the board, the semiconductor device package is mounted on the surface of the substrate. "Surface mounting method" for soldering solder has become popular. Along with this, the semiconductor device package has changed from the conventional DIP (dual in-line package) to a thin FPP (flat plastic package) suitable for high-density mounting and surface mounting.
Package). Among them, recently
Due to advances in fine processing technology, TSO with a thickness of 2 mm or less
P, TQFP and LQFP are becoming mainstream. Therefore, it is more susceptible to external influences such as humidity and temperature, and reliability such as solder heat resistance, high temperature reliability, and heat resistance reliability will become more important in the future.

In surface mounting, solder reflow is usually used for mounting. In this method, the semiconductor device package is placed on the substrate, exposed to a high temperature of 200 ° C. or higher, and the solder pre-applied to the substrate is melted to adhere the semiconductor device package to the surface of the substrate. Are exposed to high temperatures. At this time, stress such as thermal stress is applied between the sealing resin composition and each member such as the lead frame and the semiconductor chip inside the package. Therefore, if the sealing resin composition has poor adhesion, the sealing material and the inside of the package Peeling occurs between the member and a crack starting from the peeling, or moisture is deposited on the peeled portion, which lowers the reliability of the semiconductor. Therefore, in the encapsulating resin composition for semiconductors, the adhesion to the member is very important, but this peeling is more likely to occur from the silver-plated portion of the frame. This is because the silver-plated portion is inferior in adhesiveness to the resin as compared with the 42 alloy or copper which has been conventionally used. Therefore, it is very important to improve the adhesiveness to the silver-plated part, which is a factor that causes peeling.

Further, in recent years, lead-free solders containing no lead have been used from the viewpoint of environmental protection. Since the lead-free solder has a high melting point and therefore the reflow temperature also rises, the adhesive resin composition for semiconductors is required to have higher adhesiveness than ever.

It is generally known that the addition of mercaptosilane to a composition is effective as a means for improving the adhesion of the composition to a metal, and can be applied to a sealing resin composition for semiconductors. Is. However, a compound containing a mercapto group such as mercaptosilane or a composition containing the compound gives off a unique unpleasant odor, which causes an unpleasant feeling to the worker in the manufacturing process or leaves an odor in the final product. In some cases, the user may feel uncomfortable. For this reason, how to control the odor has been the biggest issue, but until now, there is no effective solution, and it is the actual situation that mercaptosilane is not used or is used with patience. there were.

[0007]

An object of the present invention is to use a mercaptosilane which has high adhesion to a semiconductor package member, particularly silver plating, and which has excellent reliability such as crack resistance during reflow. By providing a resin composition that suppresses a peculiar unpleasant odor, a high reflow temperature that eliminates operator discomfort when performing a molding process using the resin composition manufacturing process or the resin composition is achieved. It is to enable a corresponding resin-sealed semiconductor.

[0008]

In order to solve the above problems, the present invention mainly has the following configuration. That is,
"Epoxy resin (A), curing agent (B), filler (C),
An epoxy resin composition comprising a silane coupling agent (D) and a deodorant (E), wherein the silane coupling agent (D) contains mercaptosilane as an essential component, and the deodorant (E ) Contains at least one of eucalyptus oil, 1,8-cineole and propylene oxide. It is.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The constitution of the present invention will be described in detail below.

The epoxy resin composition of the present invention comprises an epoxy resin (A), a curing agent (B), a filler (C), a silane coupling agent (D) and a deodorant (E). .

The epoxy resin (A) in the present invention is not particularly limited as long as it has two or more epoxy groups in one molecule, and specific examples thereof include, for example, cresol novolac type epoxy resin and bisphenol A type epoxy. Resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, biphenyl skeleton containing epoxy resin,
Examples thereof include phenol aralkyl skeleton-containing epoxy resin, linear aliphatic epoxy resin, alicyclic epoxy resin, heterocyclic epoxy resin, halogenated epoxy resin and spiro ring-containing epoxy resin.

Among them, a biphenyl type epoxy represented by the chemical formula (I), a bisphenol F type epoxy represented by the chemical formula (II), and a biphenyl represented by the chemical formula (III) having good adhesion to the lead frame member. Skeleton-containing epoxies are preferred.

[0013]

[Chemical 1] (In the formula, R _{1 to} R ₄ represent a hydrogen atom or a methyl group.)

[0014]

[Chemical 2] (In the formula, R _{5 to} R ₁₀ represent a hydrogen atom or a methyl group.)

[0015]

[Chemical 3] (N in the formula represents 0 or an integer of 1 or more)

Two or more kinds of epoxy resins may be used in combination depending on the application, but for sealing semiconductor devices, the biphenyl type epoxy of the formula (I) and the bisphenol type epoxy of the formula (II) are used from the viewpoint of adhesion. It is preferable that 50% by weight or more is contained in the total epoxy resin (A) alone or in combination.

The compounding amount of the epoxy resin (A) is usually 5.0 to 10.0% by weight based on the whole composition.

The curing agent (B) in the present invention is not particularly limited as long as it reacts with the epoxy resin (A) and is cured. Specific examples thereof include novolac resins such as phenol novolac and cresol novolac, and bisphenol. Examples thereof include bisphenol compounds such as A, acid anhydrides such as maleic anhydride, phthalic anhydride, and pyromellitic anhydride, and aromatic amines such as metaphenylenediamine, diaminodiphenylmethane, and diaminodiphenylsulfone. Among them, a curing agent having a phenolic hydroxyl group is preferable for sealing a semiconductor device because of its excellent heat resistance, moisture resistance and storage stability. Specific examples of the curing agent having a phenolic hydroxyl group include novolac resins such as phenol novolac resin, cresol novolac resin and naphthol novolac resin, tris (hydroxyphenyl) methane, 1,1,2-tris (hydroxyphenyl) ethane, 1 , 1,3-Tris (hydroxyphenyl) propane, condensed compound of terpene and phenol, phenol resin containing dicyclopentadiene skeleton, phenol aralkyl resin, phenol resin containing biphenyl skeleton, naphthol aralkyl resin and the following chemical formulas (IV) and (V) Examples thereof include a phenol compound having a repeating unit structure represented by

[0019]

[Chemical 4]

[0020]

[Chemical 5] (R _{11 to} R ₁₈ represent a hydrogen atom or a methyl group)

As the curing agent (B), two or more types of curing agents may be used in combination depending on the application. The compounding amount of the curing agent (B) with respect to the total epoxy resin composition is usually 2.5 to 10% by weight.
The compounding ratio of the epoxy resin (A) and the curing agent (B) is usually 1.5 to 0.5 in terms of the number of functional groups.

Further, in the present invention, the epoxy resin (A)
A curing catalyst may be used to accelerate the curing reaction of the curing agent (B). The curing catalyst is not particularly limited as long as it accelerates the curing reaction, and for example, 2-methylimidazole,
Imidazole compounds such as 2,4-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, triethylamine, benzyldimethylamine, α-methylbenzyl Methylamine, 2- (dimethylaminomethyl) phenol,
Tertiary amine compounds such as 2,4,6-tris (dimethylaminomethyl) phenol, 1,8-diazabicyclo (5,4,0) undecene-7 and salts thereof, zirconium tetramethoxide, zirconium tetrapropoxide, Organometallic compounds such as tetrakis (acetylacetonato) zirconium and tri (acetylacetonato) aluminum, and triphenylphosphine, trimethylphosphine, triethylphosphine, tributylphosphine, tri (p-methylphenyl) phosphine, tri (nonylphenyl) phosphine, Organic phosphine such as tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetrabenzoic acid borate, tetraphenylphosphonium tetranaphthoic acid borate Emissions compounds and such salts thereof. Particularly preferred are triphenylphosphine, 1,8-diazabicyclo (5,4,0) undecene-7, tetraphenylphosphonium tetraphenylborate and the like.

Two or more of these curing catalysts may be used in combination depending on the intended use, and the blending amount is preferably in the range of 0.1 to 10 parts by weight with respect to 100 parts by weight of the epoxy resin (A).

The type of the filler (C) in the present invention is preferably spherical fused silica (c), and the proportion thereof is preferably 80% by weight or more based on the whole filler (C). Generally, the moldability such as fluidity deteriorates as the proportion of the filler (C) increases, but the use of spherical fused silica (c) can further suppress the deterioration of fluidity. Regarding the particle size of the spherical fused silica (c), the average particle size (median size) is preferably 20 μm or less. It is also possible to mix and use spherical silica having different particle size distributions.

The compounding ratio of the filler (C) is preferably 80 to 96% by weight in the total resin composition. Further, since it is possible to deal with "lead-free solder" such that the solder reflow temperature becomes 260 ° C, it is more preferable that the proportion of the filler (C) is 85% by weight or more and 96% by weight or less. . If the proportion of the inorganic substance in the entire resin composition is increased in this way, the flame retardancy is increased, and the flame retardancy can be maintained without using the flame retardant and the flame retardant aid which have been conventionally used. . This eliminates the need to add a halogen compound, which has been conventionally used as a flame retardant, to the resin composition, which is preferable in terms of environmental protection.

Two or more kinds of fillers can be used together depending on the application. The filler is preferably an inorganic filler, specifically, fused silica, crystalline silica, calcium carbonate, magnesium carbonate, alumina, magnesia,
Examples include clay, talc, calcium silicate, titanium oxide, asbestos, and glass fiber. The shape and average particle size of the filler used together are not particularly limited, but spherical is preferable from the viewpoint of fluidity and moldability, and the average particle size is 2
It is preferably 0 μm or less.

It is essential that the silane coupling agent (D) in the present invention contains mercaptosilane for the purpose of improving reliability. The mercaptosilane may be a silane compound having a mercapto group,
Specific examples of the mercaptosilane include, but are not limited to, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-mercaptopropyltriethoxysilane, and γ-mercaptopropylmethyldiethoxysilane. Not a thing. Two or more kinds of silane coupling agents can be used in combination depending on the application (including the use of plural kinds of mercaptosilane), and a known silane coupling agent can be used as the silane coupling agent used in combination. . Specific examples thereof include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, N-β (aminoethyl) γ-
Examples thereof include aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane and γ-ureidopropyltriethoxysilane.

The compounding amount of the silane coupling agent (D) is
From the viewpoint of moldability and reliability, usually 0.1 to 5 parts by weight, preferably 0.2 to 3 parts by weight, relative to 100 parts by weight of the filler,
It is particularly preferably 0.3 to 1.5 parts by weight. The silane coupling agent (D) can be added by mixing with other components, but in the present invention, the surface treatment of the filler (C) with the silane coupling agent (D) in advance, It is preferable in terms of improving reliability, adhesiveness and fluidity.

In the present invention, the silane coupling agent (D) contains mercaptosilane as an essential component, and the deodorant (E) contains at least one of eucalyptus oil, 1,8-cineole and propylene oxide. It is characterized in that it is contained as a component. By using any of eucalyptus oil, 1,8-cineole and propylene oxide, it is possible to eliminate the unique odor caused by using mercaptosilane.
There is no discomfort for workers or users of final products.

The eucalyptus oil in the present invention is an essential oil obtained by distilling leaves of a eucalyptus plant, and known eucalyptus oil can be used. Eucalyptus oil usually contains 50% by weight or more of 1,8-cineole as a main component, but such eucalyptus oil is also preferable in the present invention. The eucalyptus oil, 1,8-cineole or propylene oxide may be added alone, or may be added in combination by mixing two or more kinds thereof, or may be mixed in advance with the silane coupling agent (D). It is effective in terms of dispersibility and deodorizing effect when added, and is preferable, but the addition method is not limited to this.

The blending amount of eucalyptus oil, 1,8-cineole or propylene oxide is such that the total weight of eucalyptus oil, 1,8-cineole and propylene oxide in the deodorant (E) in the epoxy composition is 0. It is effective from the viewpoint of deodorizing effect that the amount is in the range of 001 to 0.2% by weight, and it is preferable, but the compounding amount is not limited to this. The ratio β / α of the weight α of the silane coupling agent (D) in the epoxy resin composition to the total weight β of the eucalyptus oil, 1,8-cineole and propylene oxide in the deodorant (E).
It is effective in terms of deodorizing effect that the addition amount is between 0.002 and 0.05, which is preferable, but the addition amount is not limited to this.

The epoxy resin composition of the present invention contains carbon black, a coloring agent such as iron oxide, silicone rubber,
Styrene block copolymers, olefin polymers, elastomers such as modified nitrile rubber and modified polybutadiene rubber, thermoplastic resins such as polystyrene, coupling agents such as titanate coupling agents, long chain fatty acids, metal salts of long chain fatty acids. A long-chain fatty acid ester, a long-chain fatty acid amide, a release agent such as paraffin wax, and a cross-linking agent such as an organic peroxide can be optionally added.

The epoxy resin composition of the present invention is preferably produced by melt kneading. Specifically, the raw materials are mixed to some extent with a mixer or the like, and the mixed raw materials are mixed at a temperature of 60 to 140 ° C. using a known kneading method such as Banbury mixer, kneader, roll, single-screw or twin-screw extruder, and cokneader. It is manufactured by melt-kneading in the temperature range of. This epoxy resin composition is usually used in the form of powder or tablet for molding a semiconductor by molding. As a method for sealing the semiconductor element, a low-pressure transfer molding method is generally used, but an injection molding method or a compression molding method is also possible. The molding conditions include, for example, an epoxy resin composition at a molding temperature of 1
A semiconductor device is manufactured by molding at 50 ° C. to 200 ° C., a molding pressure of 5 to 15 MPa, and a molding time of 30 to 300 seconds to obtain a cured product of an epoxy resin composition. Further, if necessary, the above-mentioned molded product is subjected to additional heat treatment at 100 to 200 ° C for 2 to 15 hours.

[0034]

EXAMPLES The present invention will be specifically described below with reference to examples.

[Examples 1 to 10 and Comparative Examples 1 to 8] The raw materials used in the present invention are as follows. <Epoxy resin>4,4'-bis (2,3-epoxypropoxy) -3,3 ', 5,5'-tetramethylbiphenyl (epoxy equivalent 193) <Curing agent> Phenol aralkyl resin having a hydroxyl equivalent of 175 <Inorganic filler> Amorphous spherical fused silica having an average particle size of about 10 μm <Silane coupling agent I> γ-mercaptopropyltrimethoxysilane <silane coupling agent II> γ-aminopropyltrimethoxysilane <silane coupling Agent III> γ-glycidoxypropyltrimethoxysilane (silane coupling agent was previously mixed with inorganic filler) <Deodorant I> Eucalyptus oil (manufactured by Sigma-Aldrich) <Deodorant II > 1,8-Cineol (deodorant III> propylene oxide <curing accelerator> triphenylphosphine <colorant> carbon black The amount is the same and is 0.2% by weight based on the resin composition. <Release agent> Carnauba wax (the compounding amount is the same and 0.3% by weight based on the resin composition) Each component is shown in Tables 1 to 4. The composition ratio was dry blended with a mixer.

In the examples and comparative examples in which the deodorant is added, the deodorant and the silane coupling agent are mixed in advance and then mixed with the inorganic filler. This was heated and kneaded for 5 minutes using a mixing roll having a roll surface temperature of 90 ° C., cooled and pulverized to produce an epoxy resin composition for semiconductor encapsulation. The blending amounts of carbon black and carnauba wax in the composition are uniform, and are therefore omitted from the table. The numbers in the table represent% by weight.

Each test of this example was conducted by the following test methods.

<Deodorant Test> (1) Process In the process of producing the epoxy resin compositions of Examples and Comparative Examples, five arbitrarily selected panelists (testers) selected mercaptosilane for each Example and Comparative Example. We examined whether or not the peculiar unpleasant odor was suppressed. It was carried out by evaluating the expression of unpleasant odor in five stages shown in Table 5 at a distance of 1.5 m from the mixer during dry blending, and determining the average value. The average value is rounded off to one decimal place.

[0039]

[Table 1]

(2) Using the epoxy resin compositions of the product examples and comparative examples, a diameter of 20
About 3 kg of a cylindrical tablet having a height of 23 mm and a height of 23 mm was prepared.
Put this in a polyethylene bag, seal it once, and
After cooling in a refrigerator at 5 ° C for 2 weeks, the polyethylene bag was taken out from the refrigerator and left for 24 hours, and the polyethylene bag was opened, and the appearance of an unpleasant odor was examined by the above 5 panelists 50 cm away from the bag. Regarding the evaluation method, evaluation was carried out in five stages shown in Table 5, and the average value was calculated.
The average value is rounded off to one decimal place.

(3) Silane γ-mercaptotrimethoxysilane and each deodorant were mixed in the ratio shown in Table 6. This was well stirred, weighed 50 cc in a 100 cc beaker, and the appearance of unpleasant odor was examined by the panelists of the above 5 persons. Regarding the evaluation method, evaluation was carried out in five stages shown in Table 5, and the average value was calculated. The average value is rounded off to one decimal place.

<Reliability Test> The resin compositions of Examples and Comparative Examples were used to perform 175 by low pressure transfer molding.
Chip size 10x10m with simulated device with nitride film on the surface under conditions of 90 ℃ and 90 seconds cure time
160 pin QFP of m (outer shape: 28 × 28 × 3.4 m)
m, frame material: copper, lead frame part: silver plating)
Was molded, post-cured under the conditions of 175 ° C. for 4 hours, and the physical properties of each resin composition were evaluated by the following physical property measuring methods. The post cure was 175 ° C. for 4 hours.

Crack resistance: 20 pieces of the above 160pinQFP were molded, post-cured, and then 85 ° C./60% RH
After being humidified for 168 hours, heat treatment was performed for 2 minutes in an IR reflow furnace having a maximum temperature of 260 ° C., and the number of packages with external cracks was visually examined.

Adhesion: 20 pieces of the above 160pinQFP were molded, post-cured, and then 16 at 85 ° C./60% RH.
After humidifying for 8 hours, 2 in an IR reflow furnace with a maximum temperature of 260 ° C
After heat treatment for minutes, the peeling condition of the chip surface of the lead frame and the silver-plated part was observed with an ultrasonic flaw detector ("mi-scope10" manufactured by Hitachi Construction Machinery Co., Ltd.), and the number of packages in which peeling occurred for each Examined.

Tables 2 to 5 show the evaluation results.

[0046]

[Table 2]

[0047]

[Table 3]

[0048]

[Table 4]

[0049]

[Table 5] As shown in Tables 1 and 2, the epoxy resin composition of the present invention exhibits excellent properties such as crack resistance and adhesion.
The odor is suppressed and it does not cause discomfort.

On the other hand, in Comparative Examples 1 to 5 of Tables 3 and 4 which do not contain mercaptosilane, the adhesion and crack resistance are inferior, but the eucalyptus oils of Comparative Examples 6 to 8 are inferior. Since neither cineol nor propylene oxide was added, an unpleasant odor was developed.

[0051]

[Table 6]

Further, as shown in Table 6, when each deodorant is added to mercaptosilane, an unpleasant odor is suppressed. Thus, by adding the specific substance, the unpleasant odor peculiar to mercaptosilane can be suppressed, and excellent performances in crack resistance and adhesion can be exhibited.

[0053]

EFFECT OF THE INVENTION An epoxy resin composition comprising an epoxy resin (A), a curing agent (B), a filler (C), a silane coupling agent (D) and a deodorant (E), The silane coupling agent (D) contains mercaptosilane as an essential component, and the deodorant (E) is eucalyptus oil, 1,
By containing at least one of 8-cineol and propylene oxide, the unpleasant odor peculiar to mercaptosilane can be suppressed, and excellent performance in crack resistance and adhesion can be exhibited.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 23/31 H01L 23/30 R // (C08L 63/00 91:00) F term (reference) 4J002 AE053 CC042 CC052 CD011 CD021 CD051 CD061 CD111 CD121 CD131 CE002 DE077 DE137 DE147 DE237 DE267 DJ007 DJ017 DJ027 DJ047 DL007 EJ046 EL059 EL089 EX059 EX068 EX078 EX088 FA047 FD017 FD142 FD146 FD159 FD203 GQ01 4M109 A01

Claims (8)

[Claims] 1. An epoxy resin composition comprising an epoxy resin (A), a curing agent (B), a filler (C), a silane coupling agent (D) and a deodorant (E). The silane coupling agent (D) contains mercaptosilane as an essential component, and the deodorant (E) is eucalyptus oil, 1,
An epoxy resin composition containing at least one of 8-cineole and propylene oxide. 2. An epoxy resin composition characterized in that the deodorant (E) contains two or more kinds of eucalyptus oil, 1,8-cineole and propylene oxide. 3. The total weight of eucalyptus oil, 1,8-cineole and propylene oxide in the deodorant (E) in the epoxy composition is 0.001 to 0.2% by weight. The epoxy resin composition according to claim 1. 4. The ratio β / α of the weight α of the silane coupling agent (D) and the total weight β of the eucalyptus oil, 1,8-cineole and propylene oxide in the deodorant (E) is 0.00.
It is 2 to 0.02, The claim 1 or 2 characterized by the above-mentioned.
The epoxy resin composition according to any one of 1. 5. A method for producing an epoxy resin composition comprising an epoxy resin (A), a curing agent (B), a filler (C), a silane coupling agent (D) and a deodorant (E). The deodorant (E) contains at least one of eucalyptus oil, 1,8-cineole and propylene oxide, and the coupling agent (D) and the deodorant (E) were confused in advance. Then, the method for producing an epoxy resin composition, which comprises blending with other components. 6. A semiconductor device, which is encapsulated with the cured product of the epoxy resin composition according to any one of claims 1 to 4. 7. A semiconductor device, which is encapsulated with a cured product of an epoxy resin composition obtained by the manufacturing method according to claim 5. 8. Mercaptosilane and eucalyptus oil, 1,8-
A method for masking a mercapto odor by mixing at least one of cineole and procylene oxide.