JP2003292569A - Epoxy resin composition and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an epoxy resin composition giving such semiconductor devices that make less resistance against being cut off and separated from each other, when the devices are produced after integrally sealing semiconductor elements having metal frames by using the composition, therefore are easily separated from each other, and make cutter blades less abraded, and to provide the semiconductor device by using the composition. <P>SOLUTION: This epoxy resin composition contains (A) at least one kind of epoxy resin selected from phenol aralkyl-type epoxy resins (having a phenylene skeletal structure, a biphenylene skeletal structure, etc.), and naphtol aralkyl-type epoxy resins (having a phenylene skeletal structure), (B) at least one kind of phenol resin selected from phenol aralkyl resins (having a phenylene skeletal structure, a biphenylene skeletal structure, etc.), and naphtol aralkyl resins (having a phenylene skeletal structure) (C) an accelerator, (D) a metal hydroxide containing 20 wt.% or more crystallization water and/or a metal hydroxide solid solution containing 20 wt.% or more crystallization water in an amount of 0.5-30 wt.% based on the total weight of the composition, and (E) another inorganic filler as essential ingredients. <P>COPYRIGHT: (C)2004,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 for semiconductor encapsulation suitable for MAP molding in which a semiconductor element having a metal frame is encapsulated and then the molded product is cut into individual pieces, and a semiconductor device. It is a thing.

[0002]

2. Description of the Related Art Semiconductor elements such as ICs and LSIs are mainly sealed with an epoxy resin composition which is a thermosetting resin composition to form a semiconductor device. In the recent market trend of miniaturization, weight reduction, and high performance of electronic devices, semiconductor devices are highly integrated, and the surface mounting of semiconductor devices is promoted. It is becoming tough. 2. Description of the Related Art In recent years, semiconductor devices have been changed to surface mount types such as TSOP, TQFP, BGA and the like with the high integration of integrated circuits. In particular, in order to reduce the size and thickness and improve the productivity at the same time, MAP molding in which a large number of elements are collectively molded and then cut into solid pieces after molding is also under study.

The MAP molded product has a low viscosity of the resin for molding a thin and large molded product, strength that can withstand cutting when individualized, flexibility that does not crack, and wear of a cutting blade. Sex is required. The epoxy resin composition used for surface-mount type semiconductor devices contains a low-viscosity resin component in order to withstand the thermal stress at the time of mounting, and the inorganic filler is highly filled to lower the moisture absorption rate. Or, crystalline epoxy resin such as biphenyl type epoxy resin or dicyclopentadiene modified phenol type epoxy resin, which is more tougher than conventional orthocresol novolac type epoxy resin, has come to be used. There is also a problem that the resistance is high and the blade is easily worn, and there is a problem that the blade is bitten and broken when it is singulated, and it is not sufficiently satisfactory in terms of easiness of singulation and abrasion of the blade.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides a MAP type semiconductor device in which a semiconductor element having a metal frame is collectively sealed and then a molded product is cut into individual pieces.
The present invention provides a semiconductor device that can be easily separated into individual pieces and has less wear of a cutting blade.

[0005]

The present invention provides [1] (A)
At least one of the epoxy resins represented by the formulas (1) to (4) is used.
Or more, (B) at least one or more phenolic resins represented by the formulas (5) to (8), (C) a curing accelerator (D) a metal hydroxide containing 20% by weight or more of crystal water, and / Or 0.5% by weight or more and 30% by weight or less of the total composition of a metal hydroxide solid solution containing 20% by weight or more of water of crystallization,
(E) Epoxy resin composition containing other inorganic filler as an essential component,

[Chemical 3]

[Chemical 4] [2] A semiconductor device comprising a semiconductor element having a metal frame sealed with the epoxy composition as described in the item [1], and then cutting the molded product into individual pieces.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The epoxy resin used in the present invention is a phenol aralkyl type epoxy resin (having a phenylene skeleton, a biphenylene skeleton or the like) or a naphthol aralkyl type epoxy resin represented by the formulas (1) to (4). (Having a phenylene skeleton). Molded products with low water absorption can be obtained by using these resins, so that molded products with excellent solder heat resistance and flexibility can be obtained. To facilitate. These may be used alone or in combination of two or more.

It is also possible to use other epoxy resins in combination as long as the characteristics of the epoxy resin are not impaired. For example, biphenyl type epoxy resin, hydroquinone type epoxy resin, bisphenol F type epoxy resin, bisphenol A type epoxy resin, orthocresol novolac type epoxy resin, phenol novolac type epoxy resin, dicyclopentadiene modified phenol type epoxy resin, triphenolmethane type epoxy resin. Examples thereof include resins, alkyl-modified triphenol methane type epoxy resins, and triazine nucleus-containing epoxy resins, but are not limited thereto. Also, even if these are used alone,
You may use 2 or more types together. In particular, a biphenyl type epoxy resin, a bisphenol A type epoxy resin, and a hydroquinone type epoxy resin, which can achieve a low viscosity of the composition, are preferable. The combined ratio is preferably 50% or less in the epoxy resin. If it is used in combination more than this, the flexibility of the molded product may be deteriorated, and cracking and chipping of the molded product may occur at the time of individualization.

As the phenol resin used in the present invention, a phenol aralkyl resin (having a phenylene skeleton, a biphenylene skeleton, etc.) or a naphthol aralkyl resin (having a phenylene skeleton) represented by the formulas (5) to (8) is used.
Is mentioned. These may be used alone or in combination of two or more. When these resins are used, the water absorption rate of the molded product can be reduced, the solder heat resistance is excellent, and a flexible molded product can be obtained. To do.

Further, another phenol resin may be used in combination within a range that does not impair the characteristics of the above-mentioned phenol resin. Examples thereof include, but are not limited to, phenol novolac resin, cresol novolac resin, terpene modified phenol resin, dicyclopentadiene modified phenol resin, and triphenol methane type resin. These may be used alone or in combination of two or more. In particular, cresol novolac resin that improves the curability and strength of the composition is desirable. The combined use ratio is preferably 50% or less in the phenol resin. If it is used in combination more than this, it is difficult to balance the fluidity and the curability (it is difficult to achieve compatibility), and the flexibility of the molded product is lowered, and cracking of the molded product may occur at the time of individualization.

The equivalent ratio of the epoxy groups of all epoxy resins to the phenolic hydroxyl groups of all phenol resins is not particularly limited, but is preferably 0.7 to 1.4, particularly preferably 0.8 to 1.2. is there. If it goes out of the preferred range,
Curability, moisture resistance reliability, etc. may decrease.

The curing accelerator used in the present invention includes:
Any compound that accelerates the crosslinking reaction between the epoxy resin and the phenol resin may be used, and examples thereof include organic phosphorus compounds such as triphenylphosphine and tetraphenylphosphonium / tetraphenylborate salts, but are not limited thereto. Not something. These may be used alone or in combination of two or more.

The component (D) used in the present invention is a metal hydroxide containing 20% by weight or more of water of crystallization and / or a metal hydroxide solid solution containing 20% by weight or more of water of crystallization. The metal hydroxide is not particularly limited, for example,
Examples thereof include aluminum hydroxide and magnesium hydroxide. Further, it is also possible to use a high heat-resistant type aluminum hydroxide in which a part of it is made into boehmite, made finer, or reduced in sodium ions to raise the release start temperature of crystal water. These may be used alone or in combination of two or more. It is also possible to use a metal hydroxide solid solution in which a part of the element in the crystal of the metal hydroxide is replaced with another element such as iron, nickel, titanium and zinc to form a solid solution. These may be used alone or in combination of two or more.

The component (D) of the present invention releases crystal water when the semiconductor device is divided into individual pieces, and suppresses heat generation due to friction with the blade, thereby reducing cutting resistance and eventually wear of the blade. Be effective. As the content of crystal water in the metal hydroxide, the content of crystal water in the metal hydroxide solid solution,
It is indispensable that each content is 20% by weight or more. 20
The use of less than wt% is not preferable because the effect of suppressing heat generation due to the release of crystal water and the effect of reducing cutting resistance are not sufficiently exhibited. Further, as the addition amount of all (D) components,
It is essential that the total amount of epoxy resin composition is 0.5% by weight or more and 30% by weight or less. Particularly, 1 to 5% by weight is preferable. If it is less than the lower limit, it is not preferable because the effect of suppressing heat generation due to release of crystal water and the effect of reducing cutting resistance cannot be expected. When it exceeds the upper limit, there is a problem that the fluidity is extremely lowered and the strength of the molded article is lowered, so that cracking and chipping occur during solidification.

There are no particular restrictions on the type of other inorganic fillers used in the present invention, and those generally used for sealing materials can be used. Examples thereof include fused crushed silica, fused spherical silica, crystalline silica, secondary agglomerated silica, alumina, titanium white, and glass fiber. These may be used alone or in combination of two or more kinds. Fused spherical silica is particularly preferable. It is preferable that the shape of the particles is infinitely spherical, and the filling amount can be increased by mixing particles having different sizes. The use of spherical silica also has the advantage of improving machinability. As the content of the inorganic filler,
The total amount of epoxy resin composition is preferably 65 to 94% by weight, more preferably 75 to 91% by weight. If it is less than the lower limit, the reinforcing effect of the inorganic filler is not sufficiently expressed, and the amount of the resin component, which is a moisture absorption factor, increases, so that the moisture absorption of the cured product of the epoxy resin composition increases. There is a possibility that the semiconductor device may be easily cracked during the soldering process. If it exceeds the upper limit, the fluidity of the epoxy resin composition may be extremely lowered, and defective filling, chip shift, pad shift, or wire sweep may easily occur during molding. Further, the inorganic filler used in the present invention is preferably sufficiently mixed in advance.

In particular, it is desirable to pretreat the inorganic filler with a coupling agent before use. As a result, the strength of the molded product is improved, peeling between the lead frame and the interface of the molded product and cracking and chipping of the molded product are less likely to occur during singulation after MAP molding, and further the individualization is facilitated. is there. Examples of the treatment method include epoxy coupling agents such as γ-glycidoxypropyltrimethoxysilane and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-aminopropyltriethoxysilane, and N-β. Amino-based coupling agents such as (aminoethyl) -γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, and γ-ureidopropyltriethoxysilane, mercapto-based cups such as γ-mercaptopropyltrimethoxysilane Examples thereof include a method of diluting a ring agent and the like in a solvent, spraying and mixing, and then removing the solvent, a method of directly adding to an inorganic filler and treating with a mixer, and the like.

The epoxy resin composition of the present invention comprises (A)-
In addition to the component (E), colorants such as carbon black and red iron oxide, stress reducing agents such as silicone oil and silicone rubber, natural wax, synthetic wax, higher fatty acids and metal salts thereof, or mold release of paraffins, etc. Various additives such as agents and antioxidants can be added. The epoxy resin composition of the present invention is obtained by mixing (A) to (E) with a mixer, melt-kneading with a kneader such as a hot roll, a heating kneader, or an extruder, cooling and pulverizing. In order to manufacture a semiconductor device by sealing an electronic component such as a semiconductor element using the epoxy resin composition of the present invention, it may be cured and molded by a molding method such as a transfer mold, a compression mold, an injection mold. The epoxy resin composition of the present invention is particularly suitable for a thin semiconductor device for MAP molding.

[0017]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto. The mixing ratio is parts by weight. The surface-treated spherical silica used in Examples and Comparative Examples is 99.8 parts by weight of spherical fused silica (average particle size 15 μm, specific surface area 2.4 m ² / g) with a mixer, and γ-aminopropyltrisil 0.2 parts by weight of ethoxysilane was sprayed, stirring was continued for 15 minutes as it was, then left at room temperature for 8 hours, and passed through 150 mesh. Example 1

The epoxy resin represented by the formula (1) (softening point 58
° C, epoxy equivalent 272) 9.55 parts by weight

[Chemical 5]

A phenol resin represented by the formula (6) (XL-225 manufactured by Mitsui Chemicals, Inc., softening point 79 ° C., hydroxyl group equivalent 17)
4) 6.10 parts by weight

[Chemical 6]

Aluminum hydroxide 1 (average particle size 10 μm, containing 34% of water of crystallization) 3.00 parts by weight 1,8-diazabicyclo (5,4,0) undecene-7 (hereinafter referred to as DBU) 0.25 parts by weight Spherical fused silica (average particle diameter 26 μm, specific surface area 1.4 m ² / g) 40.50 parts by weight Surface-treated spherical silica 40.00 parts by weight Carnauba wax 0.30 parts by weight Carbon black 0.30 parts by weight using a mixer After mixing each component, the surface temperature is 9
The kneaded material sheet obtained by kneading 20 times using a biaxial roll at 5 ° C. and 25 ° C. was cooled and then pulverized to obtain a resin composition. The results are shown in Table 1.

Evaluation method Spiral flow: A spiral flow measuring mold conforming to EMMI-1-66 was used at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa, and a curing time of 120 seconds. Hot strength: Flexural strength at 260 ° C is determined by JIS K 691
It measured according to 1. The unit is N / mm ² . Thermal elastic modulus: Flexural elastic modulus at 260 ° C. is determined by JIS K 6
It was measured according to 911. The unit is N / mm ² . Cutting resistance and tool wear resistance: A 3 mm-thick test piece molded at a mold temperature of 175 ° C., an injection pressure of 6.9 MPa and a curing time of 180 seconds was post-cured at 175 ° C. for 8 hours, and was then treated in JP-B-7-18814. Was carried out using the drill wear test equipment used in. This test equipment has a drill diameter of 3 m
m, use a drill with the same blade cut, drill rotation speed 8
It was set to 50 rpm and a load of 2 kg weight (19.6 N). Each test piece is perforated 30 times for evaluation, but the test piece is perforated 30 times in order to avoid an error due to the difference in cutting condition of the blade, and an Al plate with a thickness of 3 mm is perforated before and after that, as shown below. The cutting resistance and tool wear resistance were evaluated from the values. Cutting resistance: t ₁ / tAl Tool wear: tAl ³⁰ / tAl t ₁ : Time required for piercing the first test piece tAl: Time required for piercing Al plate before test piece tAl ³⁰ : After 30th hole piercing the test piece , Al plate perforation required time The smaller the cutting resistance and the tool wear resistance, the better.

Examples 2 to 8 and Comparative Examples 1 to 5 Epoxy resin compositions were obtained in the same manner as in Example 1 according to the formulations shown in Tables 1 and 2 and evaluated in the same manner as in Example 1.
The results are shown in Tables 1 and 2. The components used in other than Example 1 are shown below.

Epoxy resin represented by the formula (2): softening point 52
℃, epoxy equivalent 237

[Chemical 7]

Epoxy resin represented by the formula (3): softening point 80
℃, epoxy equivalent 270

[Chemical 8]

Epoxy resin represented by the formula (4): softening point 61
℃, epoxy equivalent 246

[Chemical 9]

Biphenyl type epoxy resin: YX-4000 manufactured by Japan Epoxy Resin Co., Ltd., melting point 105 ° C.,
Epoxy equivalent 195 Phenol novolac resin: Softening point 80 ° C, hydroxyl equivalent 104

Phenol resin represented by the formula (5): softening point 7
2 ℃, hydroxyl equivalent 200

[Chemical 10]

Phenolic resin represented by the formula (7): softening point 9
0 ° C, hydroxyl equivalent 230

[Chemical 11]

Phenolic resin represented by the formula (8), softening point 7
2 ° C, hydroxyl equivalent 183

[Chemical 12]

Aluminum hydroxide 2: High heat resistance type, average particle size 1 μm, crystal water content 34% Magnesium hydroxide: average particle size 2 μm, crystal water content 3
1% metal hydroxide solid solution: Mg _0.8 Zn _0.2 (OH) ₂ composition, average particle size 1 μm, water content of crystallization 27% Unsintered clay: SiO 2 · H 2 O composition, average particle size 2 μm, crystal water content 13% Zinc borate: having a composition represented by 2ZnO.3B ₂ O ₃ .3.5H ₂ O, average particle size 5 μm, crystal water content 14% triphenylphosphine The crystal water content is TG / DTA analyzer, 25 ℃ ~
The weight reduction value was obtained when the temperature was raised to 700 ° C. at 5 ° C./min.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

INDUSTRIAL APPLICABILITY The semiconductor device of the present invention is easy to cut into individual pieces by molding after encapsulation at once, has less blade wear, is excellent in productivity, and is industrially useful.

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Claims (2)

[Claims] 1. (A) at least one epoxy resin represented by formula (1) to formula (4), and (B) at least one epoxy resin represented by formula (5) to (8),
(C) 0.5% by weight of a curing accelerator (D) metal hydroxide containing 20% by weight or more of crystal water, and / or a solid solution of metal hydroxide containing 20% by weight or more of crystal water in the total composition. % Or more and 30% by weight or less, (E) an epoxy resin composition containing other inorganic fillers as essential components. [Chemical 1] [Chemical 2] 2. A semiconductor device, comprising: cutting a molded product into individual pieces after sealing a semiconductor element having a metal frame with the epoxy composition according to claim 1.