JP2009173744A - Underfill agent composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an underfill agent excellent in adhession to a copper bump. <P>SOLUTION: The underfill agent composition contains 50 to 500 pts.mass inorganic filler (C) and 1 to 30 pts.mass compound (D) having 3-mercaptopropionyloxy group both to 100 pts.mass sum total of an epoxy resin (A) and a curing agent (B) which has a ratio [an equivalent of an epoxy group in the component (A)/an equivalent of a group reactive with the epoxy group in the component (B)] of 0.7 to 1.2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a resin composition suitable for making a flip chip type semiconductor device having copper bumps. Specifically, the present invention relates to a resin composition that provides a semiconductor device having excellent adhesion to a copper bump, adhesion to a substrate surface, and high temperature thermal shock resistance.

  Along with the downsizing, weight reduction, and higher functionality of electrical equipment, semiconductor mounting methods have become mainstream from pin insertion type to surface mounting. Among them, flip chip is a method in which a semiconductor chip is mounted on a wiring pattern surface of an organic substrate via a plurality of bumps, and an underfill agent is filled in a gap between the organic substrate and the semiconductor chip and a gap between solder bumps. (Patent Documents 1 and 2).

In the semiconductor device, it is necessary that peeling does not occur at the interface between the underfill agent and the die or the substrate at the time of solder reflow, or the package does not crack at the time of mounting on the substrate. In particular, with the lead-free solder, there is a need to compensate for the lowered solder adhesion with an underfill agent. Various types of lead-free bumps are used, but in recent years, materials called copper pillar bumps have become mainstream.
JP-A-2005-350646 JP 2007-56070 A

  However, the conventional underfill agent has poor adhesion to copper, and there is a problem that peeling occurs at the interface between the copper bump and the underfill material during solder reflow or temperature cycle, and the element portion is destroyed. Therefore, an object of the present invention is to provide an underfill agent that does not peel off from a copper bump even after the device is sealed with a resin, and a highly reliable package sealed with the underfill agent. .

［ｎは１〜６の整数であり、Ｒ¹は炭素数１〜６の炭化水素基及び下記式（２）〜（５）で表される基から選ばれる基である

（ｋは１〜５の整数、Ｒ^２の少なくとも１つは３−メルカプトプロピオンオキシ基であり、他のＲ^２は３−メルカプトプロピオンオキシ基又は水酸基である）

（Ｒ^３の少なくとも１つは３−メルカプトプロピオンオキシ基であり、他のＲ^３は、互いに独立に、３−メルカプトプロピオンオキシ基又は水酸基である）

（Ｒ^４の少なくとも１つは３−メルカプトプロピオンオキシ基であり、他のＲ^４は、互いに独立に、３−メルカプトプロピオンオキシ基、または水酸基である）

（Ｒ^５の少なくとも１つは３−メルカプトプロピオンオキシ基であり、残りのＲ^５は、互いに独立に、３−メルカプトプロピオンオキシ基又は水酸基である）］ That is, the present invention is as follows.
(A) Epoxy resin (B) curing agent, [Equivalent of epoxy group in component (A) / (B) Equivalent of epoxy group and reactive group in curing agent] is 0.7 to 1.2 In quantity,
(C) An inorganic filler is 50-500 mass parts with respect to (A) + (B) total 100 mass parts, and
(D) The compound having a 3-mercaptopropionyloxy group represented by the following formula (1) is 1 to 30 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B),
An underfill agent composition.

[N is an integer of 1 to 6, and R ¹ is a group selected from a hydrocarbon group having 1 to 6 carbon atoms and groups represented by the following formulas (2) to (5).

(K is an integer of 1 to 5, at least one of R ² is 3-mercaptopropionic group, the other R ² is 3-mercaptopropionic group or a hydroxyl group)

(At least one of R ³ is a 3-mercaptopropionoxy group, and the other R ³ is, independently of each other, a 3-mercaptopropionoxy group or a hydroxyl group)

(At least one of R ⁴ is a 3-mercaptopropionoxy group, and the other R ⁴ is a 3-mercaptopropionoxy group or a hydroxyl group independently of each other)

(At least one of R ⁵ is a 3-mercaptopropionoxy group, and the remaining R ⁵ is, independently of each other, a 3-mercaptopropionoxy group or a hydroxyl group)]

The cured underfill agent has a strong adhesive force to copper, and does not cause separation between the semiconductor element and the substrate even when exposed to a high temperature in a reflow process, for example.

Hereinafter, each component will be described.
(A) Epoxy Resin (A) Epoxy resin used in the present invention includes bisphenol type epoxy resin, bisphenol type epoxy resin such as bisphenol F type epoxy resin, phenol novolac type epoxy resin, novolak such as cresol novolac type epoxy resin, etc. Type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, cyclopentadiene type epoxy resin and the like, and mixtures thereof. Of these, bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred.

  An epoxy resin represented by the following formula is also preferably used.

ここで、Ｒ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、例えば、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、ｎは１〜４の整数、特に１又は２である。なお、該エポキシ樹脂を使用する場合には、その含有量は、全エポキシ樹脂中２５〜１００重量％、より好ましくは５０〜１００重量％、更に好ましくは７５〜１００重量％であることが推奨される。２５重量％未満であると組成物の粘度が上昇したり、硬化物の耐熱性が低下したりする恐れがある。該エポキシ樹脂の例としては、日本化薬社製ＭＲＧＥ等が挙げられる。

Here, R is a monovalent hydrocarbon group having 1 to 20, preferably 1 to 10, more preferably 1 to 3 carbon atoms, such as an alkyl group such as a methyl group, an ethyl group or a propyl group, a vinyl group, Examples include alkenyl groups such as allyl groups. N is an integer of 1 to 4, particularly 1 or 2. In addition, when using this epoxy resin, it is recommended that the content is 25-100 weight% in all the epoxy resins, More preferably, it is 50-100 weight%, More preferably, it is 75-100 weight%. The If it is less than 25% by weight, the viscosity of the composition may increase or the heat resistance of the cured product may decrease. Examples of the epoxy resin include MRGE manufactured by Nippon Kayaku Co., Ltd.

Examples of (B) curing agent curing agents include amines, polymercaptans, imidazoles, acid anhydrides, and dicyandiamide. Preferably, amine curing agents and acid anhydride curing agents are used. As the amine curing agent, at least one aromatic amine compound represented by the following general formulas (1) to (4) is preferable.

（式中、Ｒ^６〜Ｒ^９は、夫々、互いに独立に炭素数１〜６の１価炭化水素基、ＣＨ₃Ｓ−及びＣ₂Ｈ₅Ｓ−から選ばれる基である。）

(In the formula, R ^{6 to} R ⁹ 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— independently of each other.)

In the above formula, as the monovalent hydrocarbon group of R ^{6 to} R ⁹ , those having 1 to 6 carbon atoms, particularly those having 1 to 3 carbon atoms are preferable, and methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group , Alkyl groups such as tert-butyl group and hexyl group, alkenyl groups such as vinyl group, allyl group, propenyl group, butenyl group and hexenyl group, phenyl group, etc., or part or all of hydrogen atoms of these hydrocarbon groups And halogen-substituted monovalent hydrocarbon groups such as a fluoromethyl group, a bromoethyl group, and a trifluoropropyl group, which are substituted with a halogen atom such as chlorine, fluorine, or bromine.

  The aromatic amine-based curing agent is usually solid at normal temperature, and if blended as it is, the resin viscosity increases and the workability is remarkably deteriorated. Therefore, it is preferable to melt and mix at a temperature that does not react with the epoxy resin. That is, it is desirable to melt and mix with the epoxy resin in a temperature range of 70 to 150 ° C. for 1 to 2 hours in a blending amount described later. If the mixing temperature is less than 70 ° C, the aromatic amine curing agent may not be sufficiently compatible, and if the temperature exceeds 150 ° C, it may react with the epoxy resin and increase the viscosity. Also, if the mixing time is less than 1 hour, the aromatic 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. .

Acid anhydride curing agents include methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylhymic anhydride, pyromellitic dianhydride, maleated alloocimene, benzophenonetetracarboxylic dianhydride 3,3 ′, 4,4′-biphenyltetrabisbenzophenonetetracarboxylic dianhydride, (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydro Phthalic anhydride, 1-isopropyl-4-methyl-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic anhydride Mixtures thereof. In particular, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, 3,4-dimethyl-6- (2-methyl-1-propenyl) -1,2,3,6-tetrahydrophthal Preferred are acid anhydride, 1-isopropyl-4-methyl-bicyclo [2.2.2] oct-5-ene-2,3-dicarboxylic acid anhydride and mixtures thereof. Examples of such a curing agent are commercially available as Ricacid MH700 (manufactured by Shin Nippon Chemical Co., Ltd.), YH306, and YH307 (manufactured by Japan Epoxy Resin Co., Ltd.).

(B) The compounding quantity of a hardening | curing agent is the equivalent ratio of the epoxy group in this hardening | curing agent and a reactive group with respect to the epoxy group in a liquid epoxy resin, [Equivalent of the epoxy group in (A) component / (B) hardening. The equivalent of epoxy group and reactive group in the agent] is 0.7 to 1.2, preferably 0.8 to 1.0. When the blending molar ratio is less than the lower limit value, unreacted epoxy groups remain, resulting in a decrease in the glass transition temperature, and the adhesion may be decreased. If the upper limit is exceeded, the cured product becomes hard and brittle, and cracks may occur during reflow or temperature cycling.

(C) Inorganic filler As an inorganic filler, well-known various inorganic fillers can be used. Examples thereof include fused silica, crystalline silica, alumina, boron nitride, ticker aluminum, ticker silicon, magnesia, magnesium silicate, aluminum and the like. Of these, spherical fused silica is preferable from the viewpoint of lowering the viscosity of the composition, and spherical silica produced by a sol-gel method or a deflagration method is more preferable.

  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 in order to increase the bond strength with the resin. 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.

The particle size of the inorganic filler is preferably adjusted as appropriate depending on the gap size of the semiconductor device, that is, the width of the gap between the substrate and the semiconductor chip. The gap size is typically about 10 to 200 μm. In this case, the average particle diameter (d ₅₀ : median diameter) is 0.1 in terms of the viscosity of the underfill agent and the linear expansion coefficient of the cured product. -5 μm, preferably 0.5-2 μm. If the average particle size is less than the lower limit, the viscosity of the composition increases, making it difficult to penetrate into the gap. If the upper limit is exceeded, the filler inhibits penetration and an unfilled portion occurs. There is a fear.

Further, the inorganic filler has a particle size distribution such that the particle size of 1/2 or more of the gap size is 0.1% by mass or less, particularly 0 to 0.08% by mass of the entire inorganic filler. It is preferable to have. Preferably, an inorganic filler having an average particle size of about 1/10 or less and a maximum particle size (d ₉₈ : 98% cumulative diameter) of 1/2 or less with respect to the gap size is used. The particle size and particle size distribution of the filler can be obtained by measuring the particle size distribution by a laser light diffraction method. In addition, as a measuring method for particles having a particle size of 1/2 or more with respect to the gap size, for example, an inorganic filler and pure water are mixed at a ratio of 1: 9 (mass), and subjected to ultrasonic treatment to agglomerates. Can be used, and a particle size inspection method in which this is sieved with a filter having an opening of ½ of the gap size and the remaining amount on the sieve is weighed can be used.

It has been found that the sol-gel method or the deflagration method is most suitable for controlling the particle size and its distribution. The spherical silica produced by these methods is more spherical than fused silica and has an advantage that the particle size distribution can be easily designed. The sol-gel method and the deflagration method may be conventionally known methods.

  It is preferable that 80% by mass or more, particularly 90 to 100% by mass, and particularly 95 to 100% by mass of the total inorganic filler is spherical silica produced by a sol-gel method or a deflagration method. If it is less than 80 mass%, the fluidity | liquidity of a composition may be bad.

  As a compounding quantity of an inorganic filler (C), it is preferable to set it as 50-500 mass parts with respect to 100 mass parts of (A) epoxy resins, More preferably, it is the range of 100-400 mass parts. If it is less than the said lower limit, there exists a possibility that the expansion coefficient of hardened | cured material may become large. When the upper limit is exceeded, the viscosity of the composition increases and the penetration into the gap may be poor.

式（１）において、ｎは１〜６の整数であり、Ｒ¹は炭素数１〜６の炭化水素基、たとえばアルキル基、及び下記式（２）〜（５）で表される基からなる群より選ばれる基である。

式（２）において、ｋは１〜５の整数、Ｒ^２の少なくとも１つは３−メルカプトプロピオンオキシ基であり、他は、３−メルカプトプロピオンオキシ基又は水酸基あり、従って、式（１）のｎが１または２である。好ましくは、ｋが３であり、ｎが２であるテトラエチレングリコール ビス−３−メルカプトプロピオンオキシネートが使用される。

式（３）において、Ｒ^３の少なくとも１つは３−メルカプトプロピオンオキシ基であり、残りのＲ^３は、互いに独立に、３−メルカプトプロピオンオキシ基又は水酸基であり、従って、式（１）のｎが１〜３の整数である。好ましくは、ｎが３である、トリス−［（３−メルカプトプロピオニルオキシ）−エチル］イソシアヌレートが使用される。

式（４）において、Ｒ^４の少なくとも１つは３−メルカプトプロピオンオキシ基であり、他のＲ^４は、互いに独立に、３−メルカプトプロピオンオキシ基、または水酸基である。但し、従って、式（１）においてｎは１〜４の整数である。好ましくはｎが３で、残りのＲ^４が水酸基である、トリメチロールプロパン トリス−３−メルカプトプロピオネート及び／又はｎが４であるペンタエリスリトール テトラキス−３−メルカプトプロピオネートが使用される。

式（５）において、Ｒ^５の少なくとも１つは３−メルカプトプロピオンオキシ基であり、残りのＲ^５は、互いに独立に、３−メルカプトプロピオンオキシ基又は水酸基である。従って、式（１）において、ｎは１〜６であり、好ましくは、ｎが４である、ジペンタエリスリトール テトラキス−３−メルカプトプロピオネート、及び／又は、ｎが６であるジペンタエリスリトール ヘキサキス−３−メルカプトプロピオネートが使用される。 Thiol Compound The composition of the present invention comprises a thiol compound having a 3-mercaptopropionyloxy group represented by the following formula (1) (hereinafter sometimes referred to as “thiol compound”) as component (A) and component (B). 1 to 30 parts by weight, preferably 1 to 15 parts by weight per 100 parts by weight in total. Thereby, the adhesiveness with respect to a copper bump improves notably.

In the formula (1), n is an integer of 1 to 6, and R ¹ is a hydrocarbon group having 1 to 6 carbon atoms, such as an alkyl group, and groups represented by the following formulas (2) to (5). It is a group selected from the group.

In the formula (2), k is an integer of 1 to 5, at least one of R ² is a 3-mercaptopropionoxy group, and the other is a 3-mercaptopropionoxy group or a hydroxyl group. n is 1 or 2; Preferably, tetraethylene glycol bis-3-mercaptopropionoxynate in which k is 3 and n is 2 is used.

In the formula (3), at least one of R ³ is a 3-mercaptopropionoxy group, and the remaining R ³ is independently of each other a 3-mercaptopropionoxy group or a hydroxyl group. n is an integer of 1 to 3. Preferably, tris-[(3-mercaptopropionyloxy) -ethyl] isocyanurate, where n is 3, is used.

In Formula (4), at least one of R ⁴ is a 3-mercaptopropionoxy group, and the other R ⁴ is a 3-mercaptopropionoxy group or a hydroxyl group independently of each other. However, in formula (1), n is an integer of 1 to 4. Preferably, trimethylolpropane tris-3-mercaptopropionate and / or pentaerythritol tetrakis-3-mercaptopropionate in which n is 3 and the remaining R ⁴ is a hydroxyl group and / or n is 4 are used.

In the formula (5), at least one of R ⁵ is a 3-mercaptopropionoxy group, and the remaining R ⁵ is independently a 3-mercaptopropionoxy group or a hydroxyl group. Accordingly, in formula (1), n is 1 to 6, and preferably n is 4, dipentaerythritol tetrakis-3-mercaptopropionate and / or dipentaerythritol hexakis where n is 6. -3-Mercaptopropionate is used.

Other components The underfill agent of the present invention has flexibility such as silicone-modified epoxy resin, silicone rubber, silicone oil, liquid polybutadiene rubber, methyl methacrylate-butadiene-styrene for the purpose of reducing the stress of the cured product. Resins, pigments such as carbon functional silanes for improving adhesion, carbon black and the like, dyes, and antioxidants can be blended in amounts that do not impair the object of the present invention.

Examples of the silicone-modified epoxy resin include an alkenyl group of an alkenyl group-containing epoxy resin or an alkenyl group-containing phenol resin, and the following average composition formula H _a R ¹⁰ _b SiO _(4-ab)
(In the formula, R ¹⁰ is a substituted or unsubstituted monovalent hydrocarbon group, a is 0.01 to 0.1, b is 1.8 to 2.2, and 1.81 ≦ a + b ≦ 2.3. is there.)
The number of silicon atoms in one molecule represented by is from 20 to 400, and the number of hydrogen atoms (SiH groups) directly bonded to the silicon atom is from 1 to 5, preferably from 2 to 4, particularly two. A silicone epoxy-modified resin made of a copolymer obtained by addition reaction with an SiH group of an organopolysiloxane is preferred.

As the monovalent hydrocarbon group of R ¹⁰ in the above formula, those having 1 to 10 carbon atoms, particularly those having 1 to 8 carbon atoms are preferable, and methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert- Alkyl groups such as butyl, hexyl, octyl and decyl, alkenyl such as vinyl, allyl, propenyl, butenyl and hexenyl, aryl such as phenyl, xylyl and tolyl, and benzyl , Aralkyl groups such as phenylethyl group, phenylpropyl group, etc., and chloromethyl group, bromoethyl group, trifluoro, etc., in which part or all of hydrogen atoms of these hydrocarbon groups are substituted with halogen atoms such as chlorine, fluorine, bromine, etc. Mention may be made of halogen-substituted monovalent hydrocarbon groups such as propyl groups.

  The silicone-modified epoxy resin preferably has a structure represented by the following formula (11).

In the above formula (11), R ¹⁰ is as described above, and R ¹² is —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 —, and R ¹¹ is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n is an integer of 4 to 199, preferably 19 to 109, p is an integer of 1 to 10, and q is an integer of 1 to 10.

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 component (E)) × added amount

Preparation of Underfill Agent The underfill agent of the present invention is, for example, stirred, dissolved, or mixed with the above components (A) to (D) and optional components at the same time or separately, optionally with heat treatment. , Disperse. Although the apparatus used for these operations is not particularly limited, a lykai machine equipped with a stirring and heating apparatus, a three roll, a ball mill, a planetary mixer, and the like can be used. Moreover, you may combine these apparatuses suitably.

The underfill agent obtained by the above preparation method preferably has a viscosity of 1 to 500 Pa · s, particularly 1 to 150 Pa · s at 25 ° C. The molding method and molding conditions of the underfill agent may be known ones, but preferably 100 to 120 ° C. for 0.5 hour or longer first, then 150 to 175 ° C. for 0.5 hour or longer, Perform a heat oven cure. When heating at 100 to 120 ° C. is less than 0.5 hour, voids may occur after curing. Further, if the heating at 150 to 175 ° C. is less than 0.5 hours, sufficient cured product characteristics may not be obtained.
EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples.

Preparation of Underfill Agent A liquid epoxy resin composition was obtained by uniformly kneading each component (parts by weight) shown in Table 1 with three rolls.

In Table 1, each component is as follows.
(A) Epoxy resin Epoxy resin A1: Bisphenol F-type epoxy resin represented by the following formula (RE303S-L: manufactured by Nippon Kayaku Co., Ltd.)
Epoxy resin A2: HP4032D (Naphthalene type, manufactured by Dainippon Ink Co., Ltd.)
Epoxy resin A3: Trifunctional epoxy resin represented by the following formula (Epicoat 630H: manufactured by Japan Epoxy Resin Co., Ltd.)

(B) Curing agent Curing agent B1: Hexahydrophthalic anhydride mixture represented by the following formula (Licacid MH700: manufactured by Shin Nippon Rika Co., Ltd.)

硬化剤Ｂ２：下記式で示されるマレイン化アロオシメン（ＹＨ３０７：ジャパンエポキシレジン株式会社製）

Curing agent B2: maleated alloocimene represented by the following formula (YH307: manufactured by Japan Epoxy Resin Co., Ltd.)

硬化剤Ｂ３：３，３’−ジエチル−４，４’−ジアミノジフェニルメタン（カヤハードＡＡ：日本化薬社製）
硬化剤Ｂ４：３，３’，５，５’−テトラエチル−４，４’−ジアミノジフェニルメタン（Ｃ−３００Ｓ：日本化薬社製）

Curing agent B3: 3,3′-diethyl-4,4′-diaminodiphenylmethane (Kayahard AA: manufactured by Nippon Kayaku Co., Ltd.)
Curing agent B4: 3,3 ′, 5,5′-tetraethyl-4,4′-diaminodiphenylmethane (C-300S: manufactured by Nippon Kayaku Co., Ltd.)

(C) Inorganic filler Spherical silica: manufactured by the deflagration method in which the remaining amount of filter 1 (particle size of 25 μm or more) is 0.01% by mass and the average particle size is 2.5 μm in the following particle size inspection method. Spherical silica
Silica particle size inspection method Silica and pure water are mixed at a ratio of 1: 9 (mass), and ultrasonic treatment is performed to sufficiently break up the aggregate, and filter 1 (opening 25 μm) or filter 2 (opening 10 μm) is used. The remaining amount of silica was measured by sieving and the silica remaining on the sieve. The measurement was performed five times, and the average value was expressed as mass% as a measurement value.

(D) Compound having 3-mercaptopropionoxy group D1: Tetraethylene glycol bis-3-mercaptopropionate D2: Trimethylolpropane tris-3-mercaptopropionate D3: Tris [(3-mercaptopropionyloxy) Ethyl] isocyanurate D4: pentaerythritol tetrakis-3-mercaptopropionate D5: dipentaerythritol tetrakis-3-mercaptopropionate

比較例で使用の化合物
シランG：γ−グリシドキシプロピルトリメトキシシラン（ＫＢＭ４０３：信越化学工業株式会社製） Other ingredients Solvent: Polyethylene glycol methyl ethyl acetate (PGMEA: boiling point 146 ° C)
Curing catalyst: 2-ethyl-4-methylimidazole (2E4MZ: manufactured by Shikoku Kasei Co., Ltd.)

Compound used in comparative example Silane G: γ-glycidoxypropyltrimethoxysilane (KBM403: manufactured by Shin-Etsu Chemical Co., Ltd.)

Each composition obtained was evaluated by the following methods. The results are shown in Tables 1-3.
(1) Tg (glass transition temperature), CTE1 (linear expansion coefficient at temperatures below (Tg-30 ° C.)), CTE2 (expansion coefficient at temperatures above Tg)
A predetermined amount of the composition was heated from room temperature at a rate of 10 ° C./min and held at a temperature of 200 to 260 ° C. for 30 seconds to 5 minutes to obtain a cured product. The cured product was cooled to room temperature, a test piece of 5 mm × 5 mm × 15 mm was cut out, and the temperature was raised at 5 ° C. per minute by TMA (thermomechanical analyzer) to measure Tg.
When (Tg-30 ° C) of the cured product was less than 100 ° C, CTE1 was measured at -30 to 0 ° C, and CTE2 was measured at 150 to 180 ° C.
When (Tg-30 ° C) was 100 ° C or higher, CTE1 was measured at 50 to 80 ° C, and CTE2 was measured at 200 to 230 ° C.

(2) Void test A 10 mm x 10 mm silicon chip coated with a polyimide (PI) film on a 30 mm x 30 mm FR-4 substrate is placed in the gap of a flip chip type semiconductor device in which the gap size is about 50 μm. Each resin composition was dropped and infiltrated, and after curing at 165 ° C. for 30 minutes, the presence or absence of voids was confirmed by C-SAM (manufactured by SONIX).

(3) Adhesive strength test Each composition was injected into a truncated cone-shaped polytetrafluoroethylene mold having an upper surface diameter of 2 mm, a lower surface diameter of 5 mm, and a height of 3 mm, and this was coated with polyimide (PI) film-coated silicon. The chip was placed and cured at 150 ° C. for 3 hours. After curing, the test piece obtained by removing the polytetrafluoroethylene mold was pushed at a constant speed (1 mm / sec) to measure the shear adhesive force, and set it as the initial value. Furthermore, after holding the cured test piece in a pressure cooker tester (121 ° C./2.1 atm) for 72 hours, the adhesive strength was measured in the same manner. In any case, the number of test pieces was five, and the average value was expressed as adhesive strength.
Instead of the silicon chip, a copper plate was used, and the adhesive force was measured by the same method.

(4) Toughness value K _1c
Each composition was cured at 150 ° C. for 3 hours, and the toughness value K _1c at room temperature was measured for the obtained cured product based on ASTM # D5045.

  As can be seen from Tables 1 and 2, the composition of the example containing the predetermined thiol compound has no voids and gives a cured product having a remarkably high adhesion to copper. In contrast, the compositions of Comparative Examples 1 and 2 containing epoxy silane instead of the thiol compound had poor wettability to copper, had voids in the cured product, and had low adhesive strength.

  The adhesive composition of the present invention is particularly suitable for producing a semiconductor device connected to a substrate with bumps containing copper.

Claims (6)

(A) Epoxy resin (B) curing agent, [Equivalent of epoxy group in component (A) / (B) Equivalent of epoxy group and reactive group in curing agent] is 0.7 to 1.2 In quantity,
(C) An inorganic filler is 50-500 mass parts with respect to (A) + (B) total 100 mass parts, and
(D) The compound having a 3-mercaptopropionyloxy group represented by the following formula (1) is 1 to 30 parts by mass with respect to 100 parts by mass in total of the component (A) and the component (B),
An underfill agent composition.

[N is an integer of 1 to 6, and R ¹ is a group selected from the group consisting of hydrocarbon groups having 1 to 6 carbon atoms and groups represented by the following formulas (2) to (5).

(K is an integer of 1 to 5, at least one of R ² is 3-mercaptopropionic group, the other R ² is 3-mercaptopropionic group or a hydroxyl group)

(At least one of R ³ is a 3-mercaptopropionoxy group, and the other R ³ is, independently of each other, a 3-mercaptopropionoxy group or a hydroxyl group)

(At least one of R ⁴ is a 3-mercaptopropionoxy group, and the other R ⁴ is a 3-mercaptopropionoxy group or a hydroxyl group independently of each other)

(At least one of R ⁵ is a 3-mercaptopropionoxy group, and the remaining R ⁵ is, independently of each other, a 3-mercaptopropionoxy group or a hydroxyl group)]   (B) The underfill agent composition according to claim 1, wherein the curing agent is an amine curing agent or a peroxide curing agent. (B) The underfill agent composition of Claim 2 whose hardening agent is at least 1 sort (s) of the aromatic amine compound represented by following formula (6), (7), (8) or (9).

(In the formula, R ^{6 to} R ⁹ 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— independently of each other.)   (C) The underfill agent composition according to any one of claims 1 to 3, wherein the inorganic filler is spherical silica having an average particle diameter of 0.1 to 5 µm produced by a sol-gel method or a deflagration method. The underfill agent composition according to any one of claims 1 to 4, wherein the component (A) is selected from a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, and the following three types of epoxy resins.

(R is a monovalent hydrocarbon group having 1 to 20 carbon atoms, and n is an integer of 1 to 4)
A semiconductor device provided with the hardened | cured material of the underfill agent composition of any one of Claims 1-5.