JP2010174078A - Composition for sealing semiconductor element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the heat resistance of a silicone-modified epoxy resin composition by compounding a compound having an adamantane skeleton, and to obtain a cured product having an extremely high toughness value. <P>SOLUTION: The liquid epoxy resin composition for a semiconductor element contains (A) an adamantane derivative, (B) an aromatic amine-based curing agent, (C) a silicone-modified epoxy resin and (D) an inorganic filler. The semiconductor device is sealed with the cured product of the composition. The composition provides the cured product having strong toughness, excellent adhesion to the semiconductor element and a substrate, and excellent thermal shock resistance. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a composition for encapsulating a semiconductor element, and in particular, a composition that includes an adamantane skeleton and a silicone skeleton, has a high thermal shock resistance, and provides a cured product having excellent adhesion to the surface of the semiconductor element and excellent moisture resistance. Related to things.

  As electrical devices become smaller, lighter, and more functional, mounting methods from pin insertion type to surface mounting have become mainstream. In addition, along with the high integration of semiconductor elements, there are cases in which one side of the die size exceeds 10 mm, and the die size is increasing. In a semiconductor device using such a large die, the stress applied to the die and the sealing material increases during solder reflow, peeling occurs at the interface between the sealing material and the die and the substrate, and the package is cracked when mounted on the substrate. There is a problem of entering.

  Furthermore, since lead-containing solder cannot be used in the near future, a number of lead substitute solders have been developed. Since this type of solder has a melting temperature higher than that of lead-containing solder, the reflow temperature is also examined at 260 to 270 ° C., and the conventional liquid epoxy resin composition sealing material is even more defective. Is expected. When the reflow temperature is increased in this way, a package that has not had any problems in the past may crack during reflow, or may be peeled off from the chip interface or the substrate interface. There has been a problem that cracks occur in the resin, the substrate, the chip, and the bump portion.

  As a solution to the above problem, a resin composition containing a silicone-modified epoxy resin is known (for example, Patent Document 1). Although the composition is excellent in thermal shock resistance, further improvement is required in terms of heat resistance.

  As a resin composition excellent in heat resistance, a composition containing a compound having an adamantane skeleton and an epoxy resin, giving a cured product excellent in transparency and the like and useful as a sealant for optical elements is known. (Patent Documents 2 and 3).

JP-A-2005-146104 JP 2006-307062 A JP 2007-70407 A

  The present inventor has made various studies to improve the heat resistance of the silicone-modified epoxy resin composition by blending a compound having an adamantane skeleton. As a result of including a combination of the compound and a predetermined curing agent, the inventors have increased the heat resistance. It has been found that a cured product having not only heat resistance but also extremely high toughness can be obtained, and the present invention has been achieved.

［式中、Ｒ¹は水素原子、ハロゲン原子、炭化水素基、ハロゲン置換炭化水素基、環式炭化水素基、ハロゲン置換環式炭化水素基、水素基、カルボキシル基、及び2つのＲ^１が結合して形成された−Ｏ−から選ばれる基、ｍは０〜１５の整数、ｎは１〜１６の整数、但し、ｍ＋ｎ＝１６であり、Ｘは下記式（2）で表される基であり、

（式中、R²は水素原子、炭素数1〜4のアルキル基であり、ａは1〜5の整数、ｂは0〜4の整数、但し、1≦ａ+ｂ≦5である）
Ｙは下記の基から選ばれる基であり、
−ＣＯ₂−
−Ｏ−
−Ｎ（Ｒ³）−
（Ｒ³は水素原子又は炭素数1〜4のアルキル基である）
−Ｎ（Ｚ）−
Ｚは下記式（3）で表される基である。

］
（Ｂ）芳香族アミン系硬化剤を、（A）成分中のエポキシ基の総モル量に対して、該芳香族アミン系硬化剤中のアミノ基のモル量が０．７〜１．２になる量、
（Ｃ）下記平均組成式（７）で示されるシリコーン変性エポキシ樹脂を、（A）成分と（B）成分の合計１００質量部に対して、０．１〜５０質量部

（上記式中、Ｒ⁶は炭素数１〜４のアルキル基、Ｒ⁵は水素原子又は炭素数１〜４のアルキル基、Ｑは炭素数３〜６のアルキレン基、オキシアルキレン基、又はヒドロキシオキシアルキレン基であり、ｒは４〜１９９の整数、ｐは１〜１０の整数、ｑは１〜１０の整数である。）
（Ｄ）無機充填剤を、（Ａ）成分と（Ｂ）成分の合計１００質量部に対して５０〜６００質量部。 That is, the present invention is as follows.
A composition comprising the following (A) to (D) (A) an adamantane derivative represented by the following formula (1)

[In the formula, R ¹ is a hydrogen atom, a halogen atom, a hydrocarbon group, a halogen-substituted hydrocarbon group, a cyclic hydrocarbon group, a halogen-substituted cyclic hydrocarbon group, a hydrogen group, a carboxyl group, and two R ¹ bonds. A group selected from —O—, m is an integer of 0 to 15, n is an integer of 1 to 16, provided that m + n = 16, and X is a group represented by the following formula (2). Yes,

(Wherein R ² is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 5, b is an integer of 0 to 4, provided that 1 ≦ a + b ≦ 5)
Y is a group selected from the following groups:
−CO ₂ −
-O-
-N (R ³ )-
(R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms)
-N (Z)-
Z is a group represented by the following formula (3).

]
(B) The aromatic amine-based curing agent has a molar amount of amino groups in the aromatic amine-based curing agent of 0.7 to 1.2 with respect to the total molar amount of epoxy groups in the component (A). The amount of
(C) The silicone modified epoxy resin represented by the following average composition formula (7) is 0.1 to 50 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B).

(In the above formula, R ⁶ is an alkyl group having 1 to 4 carbon atoms, R ⁵ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Q is an alkylene group having 3 to 6 carbon atoms, an oxyalkylene group, or hydroxyoxy An alkylene group, r is an integer of 4 to 199, p is an integer of 1 to 10, and q is an integer of 1 to 10.)
(D) 50-600 mass parts inorganic filler with respect to a total of 100 mass parts of (A) component and (B) component.

  The liquid epoxy resin composition for a semiconductor device of the present invention has a high toughness value, excellent adhesion to a semiconductor element and a substrate, and gives a cured product excellent in thermal shock resistance.

Hereinafter, each component, the production method of the composition, and the curing method of the composition will be described in this order.
(A) Adamantane derivative In the above formula (1), R ¹ represents a hydrogen atom, a halogen atom, a hydrocarbon group, a halogen-substituted hydrocarbon group, a cyclic hydrocarbon group, a halogen-substituted cyclic hydrocarbon group, a hydroxyl group, or a carboxyl group. And a group selected from -O- formed by bonding two R ¹ 's. As a hydrocarbon group, a C1-C10 alkyl group and an alkoxy group are preferable, for example, a methyl group, an ethyl group, a propyl group, a butyl, a methoxy group, an ethoxy group etc. are mentioned. Examples of the halogen-substituted hydrocarbon group include a group in which one or more hydrogen atoms of the hydrocarbon group are substituted with a halogen atom, such as a trifluoromethyl group. Examples of the cyclic hydrocarbon group include a cycloalkyl group having 5 to 10 carbon atoms, such as a cyclopentyl group, a methylcyclopentyl group, a cyclohexyl group, a methylcyclohexyl group, and an ethylcyclohexyl group. Examples of the halogen-substituted cyclic hydrocarbon group include groups in which one or more hydrogen atoms of the cyclic hydrocarbon group are substituted with halogen atoms, such as a fluorocyclopentyl group, a fluorocyclohexyl group, a trifluoromethylcyclopentyl group, and a trifluoro group. Examples thereof include a methylcyclohexyl group.

In Formula (1), m is an integer of 0 to 14, n is an integer of 2 to 16, and m + n = 16.

In the formula (2), R ² is an alkyl group having 1 to 4 carbon atoms, such as methyl group, ethyl group a propyl group. A plurality of R ² may be the same or different. K is an integer of 0 to 10.

Y represents a group selected from —CO ₂ —, —O—, —N (R ³ ) —, and —N (Z) —. R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms and may be exemplified for R ² . Z represents a group represented by the following formula (3) or (4). In the formula (4), R ⁴ represents a methyl group or an ethyl group.

Preferably, the adamantane derivative is liquid at room temperature, and examples thereof include the following.

(B) Amine-based curing agent The composition of the present invention uses an amine-based curing agent. Patent Document 3 discloses that an amine-based curing agent can also be used. However, as it is described that an acid anhydride system is preferable, it has been found that a cured product having high heat resistance cannot be obtained only by combining the component (A) and an amine curing agent. Examples of the amine curing agent (B) include aromatic diaminodiphenylmethane compounds such as 3,3′-diethyl-4,4′-diaminophenylmethane, 3,3 ′, 5,5′-tetramethyl-4, 4′-diaminophenylmethane, 3,3 ′, 5,5′-tetraethyl-4,4′-diaminophenylmethane, 2,4-diaminotoluene, 1,4-diaminobenzene, 1,3-diaminobenzene, etc. An aromatic amine is preferred. These may be used alone or in combination of two or more.

  Of the above aromatic amine curing agents, those that are liquid at room temperature can be blended as they are, but if they are blended as they are, the viscosity of the resin will increase and workability will be significantly reduced. It is preferable to melt and mix in a temperature range of 70 to 150 ° C. for 1 to 2 hours at a specified blending ratio described later. If the mixing temperature is less than 70 ° C, the amine curing agent may not be sufficiently compatible, and if the mixing temperature is higher than 150 ° C, it may react with the epoxy resin and increase the viscosity. Further, if the mixing time is less than 1 hour, the amine curing agent is not sufficiently compatible and may increase the viscosity, and if it exceeds 2 hours, it may react with the epoxy resin and increase the viscosity.

  The total amount of the amine curing agent used in the present invention is the molar amount of the amino group in the aromatic amine curing agent with respect to the total molar amount of the epoxy group or oxetane group in the component (A). Is 0.7 to 1.2, preferably 0.7 to 1.1, and more preferably 0.85 to 1.05. If the blending molar ratio is less than the lower limit, unreacted amino groups remain, and the glass transition temperature may be lowered or the adhesion may be lowered. On the other hand, if the upper limit is exceeded, the cured product becomes hard and brittle, and cracks may occur during reflow or temperature cycling.

上記式中、上記式中、Ｒ⁶は炭素数１〜４のアルキル基、好ましくはメチル基、Ｒ⁵は水素原子又は炭素数１〜４のアルキル基、好ましくは水素原子またはメチル基である。Ｑは炭素数３〜６のアルキレン基、オキシアルキレン基、又はヒドロキシオキシアルキレン基であり、例えば、−ＣＨ₂ＣＨ₂ＣＨ₂−、−ＯＣＨ₂−ＣＨ（ＯＨ）−ＣＨ₂−Ｏ−ＣＨ₂ＣＨ₂ＣＨ₂−又は−Ｏ−ＣＨ₂ＣＨ₂ＣＨ₂−である。ｒは４〜１９９の整数、好ましくは１９〜１３０、より好ましくは７０〜１０９の整数であり、ｐは１〜１０の整数、ｑは１〜１０の整数、好ましくは２〜５の整数である。 (C) Silicone-modified epoxy resin The liquid epoxy resin composition of the present invention includes (C) a silicone-modified epoxy resin represented by the following formula (7).

In the above formula, R ⁶ is an alkyl group having 1 to 4 carbon atoms, preferably a methyl group, and R ⁵ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom or a methyl group. Q is an alkylene group having 3 to 6 carbon atoms, an oxyalkylene group, or a hydroxyoxyalkylene group. For example, —CH ₂ CH ₂ CH ₂ —, —OCH ₂ —CH (OH) —CH ₂ —O—CH ₂ CH ₂ CH ₂ — or —O—CH ₂ CH ₂ CH ₂ —. r is an integer of 4 to 199, preferably 19 to 130, more preferably an integer of 70 to 109, p is an integer of 1 to 10, q is an integer of 1 to 10, preferably 2 to 5. .

When blending the silicone-modified epoxy resin, it is preferable to blend the diorganosiloxane unit in an amount of 1 to 20 parts by weight, particularly 2 to 15 parts by weight, based on 100 parts by weight of the epoxy resin (A). Thereby, the stress of hardened | cured material can be reduced and the adhesiveness to a board | substrate can also be improved. Here, the amount of diorganopolysiloxane is represented by the following formula.
Polysiloxane amount = (molecular weight of polysiloxane portion / molecular weight of silicone-modified epoxy resin) × added amount

(D) Inorganic filler As (D) inorganic filler mix | blended in the epoxy resin composition of this invention, what is normally mix | blended with an epoxy resin composition can be used. Examples thereof include silicas such as fused silica and crystalline silica, alumina, silicon nitride, aluminum nitride, boron nitride, titanium oxide, glass fiber and the like.

  As a compounding quantity of an inorganic filler (D), it is preferable to set it as 50-400 mass parts with respect to 100 mass parts of total amounts of (A) component, (B) component, and (C) component, More preferably, it is 150. It is the range of -300 mass parts. If it is less than the said lower limit, the expansion coefficient of hardened | cured material is large and there exists a possibility of inducing the generation | occurrence | production of a crack in a thermal shock test. On the other hand, when the upper limit is exceeded, the viscosity increases.

  In order to increase the bond strength between the resin and the inorganic filler, the inorganic filler is preferably blended in advance with a surface treatment with a coupling agent such as a silane coupling agent or a titanate coupling agent. As such a coupling agent, epoxy silane such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N Silane cups such as aminosilanes such as -β (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, and mercaptosilanes such as γ-mercaptosilane It is preferable to use a ring agent. Here, the blending amount of the coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

In addition, various additives can be further blended in the composition of the present invention as necessary. For example, epoxy compounds or epoxy resins other than (A) and (C), solvents, thermoplastic resins, thermoplastic elastomers, organic synthetic rubbers, silicone-based low stress agents, carnauba waxes, higher fatty acids, synthetic waxes, etc. In addition, colorants such as carbon black and additives such as halogen trapping agents can be added and blended.

ここで、Ｒは水素原子、又は炭素数１〜２０、好ましくは１〜１０、更に好ましくは１〜３の一価炭化水素基であり、一価炭化水素基としては、メチル基、エチル基、プロピル基等のアルキル基、ビニル基、アリル基等のアルケニル基等が挙げられる。また、ｘは１〜４の整数、特に１又は２である。 Examples of the epoxy compound or epoxy resin other than (A) and (C) include a bisphenol F type epoxy resin, an epoxy compound represented by the following structural formula, and an epoxy resin containing a polymer thereof.

Here, R is a hydrogen atom or a monovalent hydrocarbon group having 1 to 20, preferably 1 to 10, and more preferably 1 to 3 carbon atoms, and examples of the monovalent hydrocarbon group include a methyl group, an ethyl group, Examples thereof include alkyl groups such as propyl group, alkenyl groups such as vinyl group and allyl group. X is an integer of 1 to 4, particularly 1 or 2.

  As the solvent, methyl ethyl ketone, carbitol acetate, or the like can be used.

Production method of the composition The composition of the present invention comprises the components (A) to (D), as necessary, other additives or the like simultaneously or separately, with stirring, dissolution, mixing, and heating treatment as necessary. It can be obtained by dispersing. The apparatus for mixing, stirring, dispersing and the like is not particularly limited, and a lykai machine, a three roll, a ball mill, a planetary mixer, a bead mill and the like equipped with a stirring and heating device can be used. Moreover, you may use combining these apparatuses suitably.

Curing Method of Composition The molding method of the composition of the present invention may be a known method, but preferably 100 to 120 ° C., 0.5 hour or more, particularly 0.5 to 2 hours, and then 130 Heat oven cure is performed under conditions of ˜250 ° C. and 0.5 hours or more, particularly 0.5 to 5 hours. When heating at 100 to 120 ° C. is less than 0.5 hour, voids may occur after curing. Further, if the heating at 130 to 250 ° C. is less than 0.5 hour, sufficient cured product characteristics may not be obtained.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

（Ｂ）アミン系硬化剤 ：４，４’−ジアミノ−３，３’−ジエチルジフェニルメタン（日本化薬（株）製）
（Ｃ）シリコーン変性エポキシ樹脂
共重合体：

と

との付加反応生成物
（Ｄ）無機質充填剤 ：最大粒径５３μｍ、平均粒径１０μｍの球状シリカ（（株）龍森製）
（Ｅ）溶剤 ：メチルエチルケトン
その他の成分
シランカップリング剤：ＫＢＭ４０３、γ−グリシドキシプロピルトリメトキシシラン（信越化学工業（株）製）
カーボンブラック：デンカブラック（電気化学工業（株）製）
比較例で使用の樹脂等
ＹＤＦ８１７０：ビスフェノールＦ型エポキシ樹脂（東都化成（株）製）
酸無水硬化剤 ：ＭＨ７００ （東海理化社製） [Examples 1 to 4, Comparative Examples 1 to 5]
Each resin composition was obtained by kneading the components shown below uniformly in a blending amount (parts by mass) shown in Table 1 using three rolls.
(A) Adamantane derivative (i) ARS-EPO (manufactured by Idemitsu Kosan Co., Ltd.)
(Ii) BRS-EPO (made by Idemitsu Kosan Co., Ltd.)
(Iii) BP13-EPO (made by Idemitsu Kosan Co., Ltd.)
(Iv) BP22-EPO (made by Idemitsu Kosan Co., Ltd.)

(B) Amine-based curing agent: 4,4′-diamino-3,3′-diethyldiphenylmethane (manufactured by Nippon Kayaku Co., Ltd.)
(C) Silicone-modified epoxy resin copolymer:

When

Reaction product with (D) inorganic filler: spherical silica having a maximum particle size of 53 μm and an average particle size of 10 μm (manufactured by Tatsumori)
(E) Solvent: Methyl ethyl ketone
Other components Silane coupling agent: KBM403, γ-glycidoxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.)
Carbon black: Denka Black (manufactured by Denki Kagaku Kogyo Co., Ltd.)
Resin used in comparative example YDF8170: Bisphenol F type epoxy resin (manufactured by Toto Kasei Co., Ltd.)
Acid anhydride curing agent: MH700 (manufactured by Tokai Rika Co., Ltd.)

The test shown below was done about each obtained resin composition. The results are shown in Table 2.
(1) Viscosity Viscosity at 25 ° C. was measured at a rotation speed of 4 rpm using a BH type rotational viscometer.

(2) Tg (glass transition temperature), CTE1 (expansion coefficient), CTE2 (expansion coefficient)
Each composition was cured at 120 ° C./0.5 hours + 165 ° C./3 hours to prepare a cured product test piece of 5 mm × 5 mm × 15 mm. Using this test piece, Tg when the temperature was raised at a rate of 5 ° C. per minute by TMA (thermomechanical analyzer) was measured. Moreover, the expansion coefficient in the following temperature range was measured. The temperature range of CTE1 is 50 to 80 ° C, and the temperature range of CTE2 is 200 to 230 ° C.

(3) Toughness value K _1c
Each resin composition was cured at 120 ° C./0.5 hours + 165 ° C./3 hours, and the toughness value K _1c at room temperature was measured based on ASTM # D5045 for the obtained cured product.

(4) Pressure cooker test IR reflow set to a maximum temperature of 265 ° C after placing the test semiconductor device obtained by the following method under the condition of 30 ° C / 65% RH for 192 hours (condition of JEDEC level 3) The presence or absence of cracks after passing through the furnace five times was examined using an ultrasonic diagnostic imaging machine, C-SAM, manufactured by SONIX. Next, the presence or absence of peeling after being placed in a pressure cooker in an environment of 121 ° C./2.1 atm for 336 hours was examined in the same manner as described above.

Fabrication of a semiconductor device A 10 × 10 × 0.3 mm silicon chip is fixed on a BT resin substrate having a thickness of 32 × 32 mm × 0.4 mm with a commercially available die bond agent, and the resin is applied on the chip, and then 120 ° C./0.5 hours + 165 ° C. For 3 hours to make a COB type semiconductor package.

(5) Thermal shock test The test semiconductor device obtained by the above method was placed in a condition of 30 ° C./65% RH for 192 hours and passed through an IR reflow furnace set at a maximum temperature of 265 ° C. five times. A cycle of −65 ° C. for 30 minutes and 150 ° C. for 30 minutes was examined for cracks after 250, 500, 750, and 1000 cycles in the same manner as described above, and the ratio (%) of chips in which cracks were observed was obtained. .

As can be seen from the above table, the cured products of the examples are excellent in heat resistance, and the toughness value (K _1c ) is 13% or more higher than that in the comparative example.

  The composition of the present invention provides a cured product excellent in thermal shock resistance and toughness, and is suitable for sealing a semiconductor device.

Claims (5)

A composition comprising the following (A) to (D) (A) an adamantane derivative represented by the following formula (1)

[In the formula, R ¹ is a hydrogen atom, a halogen atom, a hydrocarbon group, a halogen-substituted hydrocarbon group, a cyclic hydrocarbon group, a halogen-substituted cyclic hydrocarbon group, a hydrogen group, a carboxyl group, and two R ¹ bonds. A group selected from -O- formed as above, m is an integer of 0-15, n is an integer of 1-16, provided that m + n = 16;
X is a group represented by the following formula (2),

(Wherein R ² is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a is an integer of 1 to 5, b is an integer of 0 to 4, provided that 1 ≦ a + b ≦ 5)
Y is a group selected from the following groups:
−CO ₂ −
-O-
-N (R ³ )-
(R ³ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms)
-N (Z)-
Z is a group represented by the following formula (3)

]

(B) The aromatic amine-based curing agent has a molar amount of amino groups in the aromatic amine-based curing agent of 0.7 to 1.2 with respect to the total molar amount of epoxy groups in the component (A). The amount of
(C) The silicone modified epoxy resin represented by the following average composition formula (7) is 0.1 to 50 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B).

(In the above formula, R ⁶ is an alkyl group having 1 to 4 carbon atoms, R ⁵ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, Q is an alkylene group having 3 to 6 carbon atoms, an oxyalkylene group, or hydroxyoxy An alkylene group, r is an integer of 4 to 199, p is an integer of 1 to 10, and q is an integer of 1 to 10.)
(D) 50-600 mass parts inorganic filler with respect to a total of 100 mass parts of (A) component and (B) component. In the formula (7), R ⁶ is a methyl group, R ⁵ is a hydrogen atom, r is an integer of 70 to 109, p and q are integers of 2 to 5, and Q is —OCH ₂ —CH (OH) —CH ₂ —. The composition of claim 1, which is O—CH ₂ CH ₂ CH ₂ —. (B) The composition of Claim 1 or 2 with which an aromatic amine type hardening | curing agent is represented by following formula (8), (9), (10) or (11).

(In the formula, R ^{8 to} R ¹¹ are each independently a group selected from a monovalent hydrocarbon group having 1 to 6 carbon atoms, CH ₃ S— and C ₂ H ₅ S—.)   (E) The composition according to any one of claims 1 to 3, further comprising a solvent.   The semiconductor device sealed with the hardened | cured material of the liquid epoxy resin composition of any one of Claims 1-4.