JP2008138124A - Adhesive composition and adhesive film - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive composition providing a cured material having a low elastic modulus and excellent in adhesiveness, and an adhesive film equipped with the adhesive layer. <P>SOLUTION: The adhesive composition contains (A) 100 pts.mass polyimide resin, containing a diorganopolysiloxane residue, in which ≥15 mol% of total organic substituent bonded to a silicon atom of the residue is a phenyl group and mass of the diorganopolysiloxane residue is ≥60 mass% based on the resin, (B) 5-100 pts.mass epoxy resin, (C) 0-100 pts.mass epoxy resin curing agent and (D) an effective amount of epoxy resin curing catalyst. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an adhesive composition used for manufacturing a semiconductor device. In particular, the present invention relates to a polyimide silicone adhesive composition that is excellent in heat resistance and adhesiveness and has a significantly improved elastic modulus, and an adhesive film obtained using the composition.

  A semiconductor device (i) divides a large-diameter silicon wafer on which an IC circuit is formed into semiconductor chips in a dicing process, and (ii) leads the chip with a curable liquid adhesive (die bond material) or the like. Manufactured by thermocompression bonding to the frame, curing and fixing (mounting) the adhesive, (iii) wire bonding between the electrodes, and (iv) sealing for improved handling and protection from the external environment Is done. As sealing forms, there are hermetic sealing types such as metal sealing and ceramic sealing, and non-hermetic sealing types using resin. At present, the latter method, particularly the transfer molding method using a resin, is most commonly used because it is excellent in mass productivity and inexpensive.

  In recent years, semiconductor packages obtained by sealing have come to have a compact structure such as a package having the same size as a chip (CSP) or a complicated structure such as a package in which chips are stacked (stacked CSP, SiP). . In such a package, it is difficult to disperse the stress or the stress tends to concentrate locally, and the demand for heat resistance stress in the package is becoming stricter.

In addition, these manufactured semiconductor devices are then mounted on a printed circuit board, and lead-free solder is used in the mounting and mounting process process, and a high temperature (265 ° C.) corresponding to the solder is used. Reflow resistance is required.
In addition, the semiconductor device is used in a wide temperature range, and therefore, the semiconductor device is required to have a reliability capable of withstanding from a low temperature (−50 ° C.) to a high temperature (80 ° C.).

  On the other hand, a die bond material (adhesive) used in the manufacture of a semiconductor device joins a chip mainly composed of single crystal silicon and a substrate mainly composed of a resin, and further comprises an inorganic filler or a resin. In order to protect with the sealing material as a main component, a large stress is generated at the interface between the die bond material and its peripheral members due to a difference in characteristics such as a coefficient of thermal expansion between the members. As described above, in the manufacture of a semiconductor device, the reflow process is performed at a very high temperature, and the semiconductor device is required to have a reliability that can withstand a low temperature (−50 ° C.) to a high temperature (80 ° C.). Therefore, the generation of thermal stress due to the difference in coefficient of thermal expansion between members causes a decrease in reflow resistance and a decrease in reliability of the semiconductor device. Therefore, it is preferable that the die bond material can absorb and relax such thermal stress, and therefore, the die bond material preferably has a low elastic modulus after curing.

  Furthermore, with the miniaturization of semiconductor circuits, a film-like adhesive or adhesive film is desired as a die bond material instead of a conventional liquid adhesive. This is due to the use of an adhesive film, such as problems with liquid adhesives, such as protrusion of liquid adhesive from the end of the chip, or tilting of the chip due to uneven thickness, resulting in wire bond defects. It is because it can prevent.

  As an adhesive, a low elastic modulus material in which a siloxane structure is introduced into polyimide or polyamideimide which is a resin having excellent heat resistance is known. However, these resins are insufficient in terms of elastic modulus and adhesion to the substrate.

  Moreover, the composition which mix | blended the compound which has 2 or more maleimide groups with the siloxane modified polyamide imide, and improved the high temperature characteristic is known (for example, patent document 1). However, this composition has poor adhesion.

  A heat-resistant adhesive film made of polyimide silicone and epoxy resin is also known (for example, Patent Documents 2 to 3). The film is excellent in adhesiveness but has a problem in terms of elastic modulus.

  In order to further reduce the elastic modulus, an adhesive in which a butadiene-acrylonitrile copolymer is added to a composition of a polyimide silicone resin and an epoxy resin is known (for example, Patent Document 4). Therefore, there are disadvantages that the rubbery polymer component is separated from the adhesive composition, or unevenness is generated on the film surface when the adhesive composition is applied onto a substrate to form a film.

In addition, attempts have been made to further reduce the elastic modulus of the composition by further decreasing the elastic modulus of the polyimide silicone resin itself by increasing the organopolysiloxane content of the polyimide silicone resin. However, the dimethylpolysiloxane that has been used so far and is easily produced industrially has poor compatibility with the epoxy resin when the content becomes high, and the same problem as described above occurs. Moreover, it is inferior to adhesiveness with the sealing resin of a semiconductor device.
Japanese Patent Laid-Open No. 10-60111 Japanese Patent Laid-Open No. 7-224259 JP-A-8-27427 JP 2003-193016 A

  The present invention has been made in view of the above circumstances, and has an adhesive composition that gives a cured product having a low elastic modulus and excellent adhesiveness and heat resistance, and an adhesive film obtained by using the adhesive composition The purpose is to provide.

As a result of intensive studies to achieve the above object, the present inventor has obtained a phenyl group as an organic substituent in the adhesive composition containing a polyimide resin, an epoxy resin, and an epoxy resin curing catalyst. By using a polyimide resin containing a diorganopolysiloxane residue having a high content, compatibility with the epoxy resin is improved, and as a result, the resulting adhesive composition is a stable and smooth film molding. And a cured product having a low elastic modulus, high adhesive strength and high heat resistance.

That is, the present invention
(A) 15 mol% or more of all organic substituents containing a diorganopolysiloxane residue bonded to the silicon atom of the residue are phenyl groups, and the mass of the diorganopolysiloxane residue is 60% of the resin. 100 parts by mass of polyimide resin that is at least mass%,
(B) 5-100 mass parts of epoxy resin,
(C) 0-100 mass parts of epoxy resin curing agent,
(D) an effective amount of an epoxy resin curing catalyst,
And an adhesive film provided with an adhesive layer made of the composition.

  The adhesive composition of the present invention is excellent in stability over time, and forms a smooth surface coating film when coated on a substrate film. Moreover, this adhesive composition has a low elastic modulus, has a high adhesive force with respect to a chip | tip and various base materials, and gives the cured | curing material which is high heat resistance.

Each component of the adhesive composition of this invention is demonstrated below.
Component (A) contains a diorganopolysiloxane residue, 15 mol% or more of all organic substituents bonded to the silicon atom of the residue are phenyl groups, and the mass of the diorganopolysiloxane residue is It is a polyimide resin that is 60% by mass or more of the resin.

As said polyimide resin, the polyimide resin represented by following General formula (3) can be used.

（式中、Ｘは芳香族環又は脂肪族環を含む四価の有機基、Ｙは二価の有機基、ｑは１〜３００の整数であり、Ｙの少なくとも１つがジオルガノポリシロキサン残基である。）

Wherein X is a tetravalent organic group containing an aromatic ring or an aliphatic ring, Y is a divalent organic group, q is an integer of 1 to 300, and at least one of Y is a diorganopolysiloxane residue .)

The diorganopolysiloxane residue is preferably represented by the following formula (1).

（式中、Ｒ¹は炭素原子数３〜９の二価の有機基であり、Ｒ²〜Ｒ⁶は炭素原子数１〜８の非置換又は置換の、芳香族環を含まない一価炭化水素基であり、ｎ、ｍおよびｐは０又は１以上の整数であるが、ｍ＋ｐは１以上の整数であり、ｎ＋ｍ＋ｐは１〜１００の整数である。）

(In the formula, R ¹ is a divalent organic group having 3 to 9 carbon atoms, and R ^{2 to} R ⁶ are monovalent carbon atoms that do not contain an unsubstituted or substituted aromatic ring having 1 to 8 carbon atoms. It is a hydrogen group, and n, m and p are 0 or an integer of 1 or more, m + p is an integer of 1 or more, and n + m + p is an integer of 1 to 100.)

In the above formula (1), as R ¹ , for example, — (CH ₂ ) ₃ —, — (CH ₂ ) ₄ —, —CH ₂ CH (CH ₃ ) —, — (CH ₂ ) ₆ —, — ( CH _{2) 8} - such as an alkylene group, an arylene group, such as the following groups

、これらを組み合わせたアルキレン・アリーレン基、−（ＣＨ₂）₃−Ｏ−、−（ＣＨ₂）₄−Ｏ−等のオキシアルキレン基、オキシアリーレン基、例えば下記の基

, Alkylene / arylene groups combining these, oxyalkylene groups such as — (CH ₂ ) ₃ —O—, — (CH ₂ ) ₄ —O—, and oxyarylene groups such as the following groups:

、及びこれらを組み合わせたオキシアルキレン・アリーレン基、例えば下記の基

And oxyalkylene / arylene groups combining these, such as

などの二価炭化水素基が包含される。

And divalent hydrocarbon groups are included.

Examples of the unsubstituted or substituted monovalent hydrocarbon group not containing an aromatic ring represented by R ^{2 to} R ⁶ include, for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, Alkyl group such as butyl group, isobutyl group, tert-butyl group, hexyl group, cyclohexyl group, 2-ethylhexyl group, octyl group, vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, isobutenyl group, hexenyl group Alkenyl groups such as these, groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms such as fluorine, bromine, chlorine, etc., such as chloromethyl groups, bromoethyl groups, 3, 3 Halogen-substituted alkyl groups such as 1,3-trifluoropropyl group and the like, and methyl group is preferred.

n, m and p are 0 or an integer of 1 or more, m + p is an integer of 1 or more, n + m + p is an integer of 1 to 100, and preferably n + m + p is an integer of 1 to 50.

The polyimide resin may be a polyamic acid resin represented by the following formula (4), which is a precursor of the above (3). However, since water may be produced as a by-product due to imidization (dehydration ring closure) at the time of heat curing in the die bonding process, the adhesion surface may be peeled off. Therefore, the polyimide resin of the above (3) that has been imidized (dehydration ring closure) in advance may be used. It is preferable to use it.

（式中、Ｘ、Ｙおよびｑは上で定義したとおりである。）

(Wherein X, Y and q are as defined above.)

  In the above formulas (3) and (4), q is an integer of 1 to 300, preferably an integer of 2 to 300, particularly an integer of 5 to 300.

  The polyamic acid resin represented by the general formula (4) has the following structural formula (5).

（但し、Ｘは上で定義したとおりである。）
で表されるテトラカルボン酸二無水物と、下記構造式（６）
Ｈ₂Ｎ−Ｙ−ＮＨ₂ （６）
（但し、Ｙは上で定義したとおりである。）
で表されるジアミンとを常法に従って、ほぼ等モルで有機溶剤中で反応させることによって得ることができる。

(However, X is as defined above.)
A tetracarboxylic dianhydride represented by the following structural formula (6)
H ₂ N—Y—NH ₂ (6)
(However, Y is as defined above.)
According to a conventional method, the diamine can be obtained by reacting in a substantially equimolar amount in an organic solvent.

  The polyimide resin represented by the general formula (3) can be obtained by dehydrating and ring-closing the polyamic acid resin represented by the general formula (4) by a conventional method.

  The following are mentioned as a preferable example of the tetracarboxylic dianhydride represented by the said Formula (5), These 2 or more types of mixtures may be sufficient. In the tetracarboxylic dianhydride, X is preferably a tetravalent organic group containing an aromatic ring from the viewpoint of the heat resistance of the resulting composition.

  The polyimide resin (A) contains a diorganopolysiloxane residue, and from the point of compatibility with the epoxy resin, 15 mol% or more, preferably 15 to 50 mol, of all organic substituents bonded to the silicon atom of the residue. %, More preferably 15 to 35 mol% is a phenyl group. Furthermore, this diorganopolysiloxane residue has a mass of 60% by mass or more of the polyimide resin from the viewpoint of low elasticity, adhesion and flexibility of the resulting composition, and solubility of the polyimide resin in an organic solvent, Preferably it is 60-90 mass%.

The diorganopolysiloxane residue is preferably derived by using a diaminosiloxane compound (or α, ω-diaminopolysiloxane) represented by the following formula as the diamine of the formula (6).

（式中、Ｒ¹〜Ｒ⁶、ｎ、ｍおよびｐは上記で定義した通りである。）

(Wherein R ^{1 to} R ⁶ , n, m and p are as defined above.)

  The diaminopolysiloxanes represented by the above formula can be used alone or in combination of two or more as desired.

Examples of the diamine represented by the above formula (6) other than the diaminopolysiloxane represented by the above formula include p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, and 4,4′-. Diaminodiphenyl ether, 2,2′-bis (4-aminophenyl) propane, 4,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenyl sulfide, 1,4-bis (3-aminophenoxy) benzene, 1, 4-bis (4-aminophenoxy) benzene, 1,4-bis (p-aminophenylsulfonyl) benzene, 1,4-bis (m-aminophenylsulfonyl) benzene, 1,4-bis (p-aminophenylthioether) ) Benzene, 1,4-bis (m-aminophenylthioether) benzene, 2,2-bis [ -(4-aminophenoxy) phenyl] propane, 2,2-bis [3-methyl-4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-chloro-4- (4-aminophenoxy) ) Phenyl] propane, 1,1-bis [4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-methyl-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3-Chloro-4- (4-aminophenoxy) phenyl] ethane, 1,1-bis [3,5-dimethyl-4- (4-aminophenoxy) phenyl] ethane, bis [4- (4-aminophenoxy) ) Phenyl] methane, bis [3-methyl-4- (4-aminophenoxy) phenyl] methane, bis [3-chloro-4- (4-aminophenoxy) phenyl] methane, bis [3 5-dimethyl-4- (4-aminophenoxy) phenyl] methane, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] perfluoropropane, etc. Aromatic ring-containing diamines, and the like, preferably p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 1,4-bis (3-aminophenoxy) Benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [3-methyl-4- (4-aminophenoxy) ) Phenyl] propane and the like. These diamines can be used alone or in combination of two or more. Moreover, the usage-amount of these diamines can be 0-30 mass% of the whole diamine compound, and can be 0-10 mass% especially. If the amount is too large, the amount of diorganopolysiloxane residue introduced into the polyimide resin of the present invention may be reduced.

Moreover, (A) polyimide resin of this invention may further contain the aromatic compound residue which has a phenolic hydroxyl group. The residue can be derived from a diamine compound having a phenolic hydroxyl group, and examples thereof include the following.

（式中、Ｒ^７は独立に水素原子又はフッ素、臭素、よう素などのハロゲン原子、あるいはアルキル基、アルケニル基、アルキニル基、トリフルオロメチル基、フェニル基などの非置換又は置換の炭素原子数１〜８の一価炭化水素基であり、各芳香環に付いている置換基は全てまたは一部同じでも構わないし、全て異なっていても構わない。ここでｒは０〜５の整数である。ＡおよびＢはおのおの１種単独で用いてもよく、２種以上を組み合わせて用いてもよい。Ｒは水素原子、ハロゲン原子又は非置換もしくは置換の一価炭化水素基である。）

Wherein R ⁷ is independently a hydrogen atom or a halogen atom such as fluorine, bromine or iodine, or an unsubstituted or substituted carbon atom such as an alkyl group, alkenyl group, alkynyl group, trifluoromethyl group or phenyl group. 1 to 8 monovalent hydrocarbon groups, and all or some of the substituents attached to each aromatic ring may be the same or different, where r is an integer of 0 to 5. A and B may be used alone or in combination of two or more, and R is a hydrogen atom, a halogen atom or an unsubstituted or substituted monovalent hydrocarbon group.)

Here, as the unsubstituted or substituted monovalent hydrocarbon group having 1 to 8 carbon atoms of R ⁷ , for example, the same as those exemplified for R ² and R ³ above, and an ethynyl group, a propynyl group, Alkynyl groups such as a butynyl group and a hexynyl group can be exemplified. When R is an unsubstituted or substituted monovalent hydrocarbon group, examples of R include the same as those exemplified for R ⁷ above.

  Moreover, the following are mentioned as diamine which has another phenolic hydroxyl group.

（式中、Ｒは水素原子、フッ素、臭素、よう素などのハロゲン原子、又は炭素数１〜８の、アルキル基、アルケニル基、アルキニル基、トリフルオロメチル基、フェニル基などの非置換又はハロゲン置換の１価炭化水素基であり、各芳香族環に付いている置換基は全て同じでも異なっていても構わない。Ｚは単結合、メチレン、プロピレンである。ｒは０〜５の整数である。）

(In the formula, R is a halogen atom such as a hydrogen atom, fluorine, bromine or iodine, or an unsubstituted or halogenated alkyl group, alkenyl group, alkynyl group, trifluoromethyl group, phenyl group or the like having 1 to 8 carbon atoms. It is a substituted monovalent hydrocarbon group, and the substituents attached to each aromatic ring may be the same or different, Z is a single bond, methylene or propylene, and r is an integer of 0 to 5. is there.)

  In the present invention, among the diamine compounds having a phenolic hydroxyl group, a diamine compound represented by the following formula (2) is particularly preferable.

（式中、Ｒ^７は上記と同じである。）

(Wherein R ⁷ is the same as above)

    The amount of the diamine compound having a phenolic hydroxyl group can be 0 to 30% by mass, particularly 0 to 5% by mass, based on the entire diamine compound. If the amount is too large, the amount of diorganopolysiloxane residue introduced into the polyimide resin of the present invention may be reduced.

  In order to introduce a phenolic hydroxyl group, a monoamine having a phenolic hydroxyl group can also be used, and the following structures can be exemplified.

（式中、Ｒ^７は上記で定義した通りである。Ｄは１種でも２種を併用してもよい。また、ｓは１〜３の整数である。）

(Wherein R ⁷ is as defined above. D may be used alone or in combination of two, and s is an integer of 1 to 3).

  The monoamine having a phenolic hydroxyl group is preferably used in an amount of 0.05 to 1.0% by mass relative to the entire diamine compound. Moreover, you may use it as a mixture of 2 or more types.

  As an example of the formation reaction of a polyamic acid resin and a polyimide resin, first, tetracarboxylic dianhydride and diamine are dissolved in a solvent under an inert atmosphere, and are usually reacted at 80 ° C. or lower, preferably 0 to 40 ° C. To synthesize a polyamic acid resin. By heating the obtained polyamic acid resin to usually 100 to 200 ° C., preferably 150 to 200 ° C., the acid amide portion of the polyamic acid resin can be dehydrated and cyclized to synthesize a polyimide resin.

  The organic solvent used for the reaction may not be one that can completely dissolve the starting material as long as it is inert to the resulting polyamic acid. Examples include tetrahydrofuran, 1,4-dioxane, cyclopentanone, cyclohexanone, γ-butyrolactone, N-methylpyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide and dimethyl sulfoxide, preferably aprotic Polar solvents, particularly preferably N-methylpyrrolidone, cyclohexanone and γ-butyrolactone. These solvents can be used alone or in combination of two or more.

  In order to facilitate the dehydration ring closure, it is desirable to use an azeotropic dehydrating agent such as toluene or xylene. Further, dehydration ring closure can be performed at a low temperature using an acetic anhydride / pyridine mixed solution.

  In addition, in order to adjust the molecular weight of polyamic acid and polyimide resin, dicarboxylic acid anhydrides such as maleic anhydride and phthalic anhydride and / or aniline, n-butylamine, and monoamines having the above-mentioned phenolic hydroxyl groups are added. You can also However, the addition amount of dicarboxylic anhydride is usually 0 to 2 parts by mass per 100 parts by mass of tetracarboxylic dianhydride, and the addition amount of monoamine is usually 0 to 2 parts by mass per 100 parts by mass of diamine. Part.

As the (B) epoxy resin used in the present invention, one having at least two epoxy groups in one molecule is preferable. Examples of such epoxy resins include, for example, bis (4-hydroxyphenyl) methane, 2,2′-bis (4-hydroxyphenyl) propane, or halides thereof, diglycidyl ethers and polycondensates thereof ( So-called bisphenol F type epoxy resin, bisphenol A type epoxy resin), butadiene diepoxide, vinylcyclohexene dioxide, diglycidyl ether of resorcin, 1,4-bis (2,3-epoxypropoxy) benzene, 4,4'-bis (2,3-epoxypropoxy) diphenyl ether, 1,4-bis (2,3-epoxypropoxy) cyclohexene, bis (3,4-epoxy-6-methylcyclohexylmethyl) adipate, 1,2-dioxybenzene or resorcinol , Polyphenol or poly Epoxy novolac obtained by condensing novolak type phenol resin (or halogenated novolak type phenol resin) such as epoxy glycidyl ether or polyglycidyl ester, phenol novolak, cresol novolak and the like obtained by condensing alcohol and epichlorohydrin and epichlorohydrin ( In other words, novolac type epoxy resin), epoxidized polyolefin epoxidized by peroxidation method, epoxidized polybutadiene, naphthalene ring-containing epoxy resin, biphenyl type epoxy resin, phenol aralkyl type epoxy resin, biphenyl aralkyl type epoxy resin, cyclopentadiene type epoxy Resin etc. are mentioned.
Among these, (A) an epoxy resin having an aromatic residue is preferable because it is easily compatible with the polyimide resin.

  A monoepoxy compound may be appropriately used in combination, for example, styrene oxide, cyclohexene oxide, propylene oxide, methyl glycidyl ether, ethyl glycidyl ether, phenyl glycidyl ether, allyl glycidyl ether, octylene oxide, dodecene oxide, etc. Can be mentioned. These epoxy resins may be used alone or in combination of two or more.

Furthermore, when the adhesive composition of the present invention is applied as an adhesive film, particularly when the silicon wafer to be attached is thin, from the generation of cracks and warping, the epoxy resin used is a low temperature adhesive film of the present invention, The liquid or softening temperature is preferably 80 ° C. or lower so that pressure bonding can be performed at a low pressure.

  (B) As for the compounding quantity of an epoxy resin, 5-100 mass parts is preferable with respect to 100 mass parts of (A) polyimide resin, and it is especially preferable that it is 10-50 mass parts. When the compounding amount of the epoxy resin is less than the lower limit, the adhesive strength of the composition may be inferior. When the upper limit is exceeded, the elastic modulus of the adhesive layer may be increased or the flexibility may be insufficient.

  As the epoxy resin curing catalyst (D) used in the present invention, a known catalyst can be used, and examples thereof include phosphorus catalysts and amine catalysts.

  Examples of the phosphorus catalyst include triphenylphosphine, triphenylphosphonium triphenylborate, tetraphenylphosphonium tetraphenylborate, and compounds as shown below.

（式中、Ｒ⁸〜Ｒ¹⁵は水素原子又はフッ素、臭素、よう素などのハロゲン原子、あるいは炭素原子数１〜８のアルキル基、アルケニル基、アルキニル基、又は炭素原子数１〜８のアルコキシ基、トリフルオロメチル基、フェニル基などの非置換もしくは置換一価炭化水素基であり、総ての置換基が同一でも、おのおの異なっていても構わない。）

(Wherein R ^{8 to} R ¹⁵ are a hydrogen atom or a halogen atom such as fluorine, bromine, iodine, or an alkyl group, alkenyl group, alkynyl group, or alkoxy having 1 to 8 carbon atoms) A non-substituted or substituted monovalent hydrocarbon group such as a group, a trifluoromethyl group or a phenyl group, and all the substituents may be the same or different.)

Here, examples of the monovalent hydrocarbon group of R ^{8 to} R ¹⁵ are the same as those exemplified for R ⁷ above, and alkoxy groups such as a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, and a butoxy group. Can be mentioned.

  Examples of the amine catalyst include imidazole derivatives such as dicyandiamide, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and the like. It is done.

Among these catalysts, particularly preferred catalysts are dicyandiamide and 2-phenyl-4,5-dihydroxymethylimidazole having a high melting point because of the storage stability of the adhesive composition of the present invention.

  These epoxy resin curing catalysts can be used alone or in combination of two or more. The compounding amount of the epoxy resin curing catalyst is not particularly limited as long as it is an effective amount as a catalyst, but is usually 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the epoxy resin. It is.

The composition of this invention may mix | blend the hardening | curing agent for (C) epoxy resins. As the curing agent, various conventionally known ones can be used, such as diethylenetriamine, triethylenetetramine, diethylaminopropylamine, N-aminoethylpiperazine, bis (4-amino-3-methylcyclohexyl) methane, Amine compounds such as metaxylylenediamine, menthanediamine, 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro (5,5) undecane; epoxy resin-diethylenetriamine adduct, amine -Modified aliphatic polyamines such as ethylene oxide adducts, cyanoethylated polyamines; bisphenol A, trimethylol allyloxyphenol, low polymerization degree phenol novolac resins, epoxidized or butylated phenol resins or Super Be ckcite 1001 (manufactured by Nippon Reichhold Chemical Co., Ltd.), Hitanol 4010 (manufactured by Hitachi, Ltd.), Scadoform L. A phenolic resin containing at least two phenolic hydroxyl groups in the molecule, such as a phenolic resin known under a trade name such as 9 (made by Scado Zwoll, the Netherlands) and Methylon 75108 (made by General Electric, USA); . 138 (manufactured by Nihon Reichhold Chemical Co., Ltd.), Melan (manufactured by Hitachi, Ltd.), U-Van 10R (manufactured by Toyo Kodan Kogyo Co., Ltd.), etc. , Amino resins such as aniline resins; 1 as shown by the formula HS (C ₂ H ₄ OCH ₂ OC ₂ H ₄ SS) _n C ₂ H ₄ OCH ₂ OC ₂ H ₄ SH (n = 1 to an integer of 1 to 10) Polysulfide resins having at least two mercapto groups in the molecule; organics such as phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, pyromellitic anhydride, methyl nadic acid, dodecyl succinic anhydride, chlorendic anhydride An acid or an anhydride thereof (an acid anhydride) may be used. Among the curing agents described above, a phenolic resin (phenol novolac resin) is desirable because it provides good molding workability, provides excellent moisture resistance, is non-toxic and is relatively inexpensive. The above-mentioned curing agents are not necessarily limited to one type in use, and two or more types may be used in combination depending on the curing performance of the curing agents.

Although the usage-amount of this hardening | curing agent is suitably adjusted, generally it is 0-100 mass parts with respect to 100 mass parts of said polyimide resins, More typically, it is the range of 5-50 mass parts. When the amount exceeds 100 parts by mass, it is economically disadvantageous, and the epoxy resin is diluted so that it takes a long time to cure, and further, there may be a disadvantage that the physical properties of the cured product are lowered.

  Furthermore, in the composition of the present invention, silica fine powder, alumina, titanium oxide, carbon black, fillers such as conductive particles, inorganic or organic fillers, pigments, dyes, etc. are colored to the extent that the properties are not impaired. Additives such as an agent, a wetting improver, an antioxidant, and a heat stabilizer can be blended.

In particular, silica fine particles and silicone fine particles having a particle diameter of 10 μm or less are preferable.

Silica particles and silicone fine particles moderately increase the melt viscosity of the adhesive layer, suppress chip flow in the resin sealing process, and reduce the moisture absorption and linear expansion coefficient of the cured product. The particle size is 10 μm, preferably 5 μm or less, and the maximum particle size is 20 μm or less. If the average particle size exceeds this range, the smoothness of the surface of the adhesive film of the present invention may be impaired. The silica particles are preferably surface-treated with an organosilicon compound from the viewpoint of fluidity of the composition.

Silica particles include reinforcing properties such as fumed silica and precipitated silica, and crystalline silica such as silica quartz. Specifically, Aerosil R972, R974, R976, manufactured by Nippon Aerosil Co., Ltd., SE-2050, SC-2050, SC-2050, SE-1050, SO-E1, SO-C1, SO- from Admatechs Co., Ltd. Examples include E2, SO-C2, SO-E3, SO-C3, SO-E5, SO-C5, Musil 120A and Musil 130A manufactured by Shin-Etsu Chemical Co., Ltd., and a mixture thereof.

The compounding amount of the silica particles is preferably 5 to 60% by mass, particularly 10 to 45% by mass, based on the total mass of the composition. If it is less than these ranges, the effect of lowering the moisture absorption rate and linear expansion coefficient of the cured product is lost, and if it exceeds the above range, the elastic modulus of the cured product may increase.

  As the silicone fine particles, composite silicone rubber fine particles are preferable. The composite silicone rubber fine particles are particles in which microorganisms of a polyorganosilsesquioxane resin produced by polymerization on the surface are present on at least a part of the surface of the silicone rubber particles. By compounding the composite silicone rubber fine particles, it is possible to achieve a decrease in the elastic modulus and water absorption rate of the cured product in combination with the silica particles.

The composite silicone rubber fine particles have an average particle size of 0.1 to 10 μm, preferably 0.5 to 5 μm. If the average particle size exceeds this range, the smoothness of the surface state of the adhesive film of the present invention may be impaired. Moreover, it is preferable that a maximum particle size is 20 micrometers or less, More preferably, it is 10 micrometers or less.

The compounding quantity of composite silicone rubber microparticles is 5-30 mass% of the composition total mass, Preferably it is 10-20 mass%. Outside these ranges, effects on the elastic modulus and water absorption of the cured product cannot be obtained, and the linear expansion coefficient of the cured product may increase and the strength may decrease.

The composite silicone rubber fine particles can be produced, for example, according to the method described in JP-A-7-196815. That is, an alkaline substance or an alkaline aqueous solution and an organotrialkoxysilane are added to an aqueous dispersion of spherical silicone rubber fine particles having an average particle size of 0.1 to 10 μm, and the organotrialkoxysilane is added on the surface of the spherical silicone rubber fine particles. Hydrolyze and polymerize, then dry it. The amount of the polyorganosilsesquioxane resin is preferably 1 to 500 parts by mass, more preferably 2 to 100 parts by mass with respect to 100 parts by mass of the silicone rubber spherical fine particles. If the amount is less than the lower limit, the dispersibility of the composite silicone rubber fine particles in the present adhesive composition may be deteriorated and the film composition may be nonuniform. On the other hand, when it exceeds the said upper limit, there exists a tendency for the elasticity modulus of adhesive hardened | cured material to become high.

As the composite silicone rubber fine particles, for example, KMP-600, KMP-605, X-52-7030 and the like manufactured by Shin-Etsu Chemical Co., Ltd. can be used. A mixture of two or more of these can also be used.

  The adhesive composition of the present invention can be used, for example, by dissolving the adhesive composition in an aprotic polar solvent such as toluene, cyclohexanone, or NMP at an appropriate concentration, coating the substrate, drying it, and applying the adhesive composition. Crimp the body and heat cure. Also, an adhesive composition dissolved in an appropriate concentration in a solvent is applied onto a support substrate and dried to obtain a film in which an adhesive layer is formed (hereinafter referred to as an adhesive film). The substrate and the adherend may be sandwiched and pressure-bonded, and then heat-cured and bonded. As the support substrate, polyethylene, polypropylene, polyester, polyamide, polyimide, polyamideimide, polyetherimide, polytetrafluoroethylene, paper, metal foil or the like, or those obtained by releasing the surface can be used. .

  As drying conditions after apply | coating an adhesive composition, it is preferable to set it as normal temperature -200 degreeC, especially 80-150 degreeC for 1 minute-1 hour, especially 3-10 minutes. There is no restriction | limiting in particular in the film thickness of an adhesive bond layer, It can select according to the objective, Usually, it is 10-100 micrometers, Preferably it is 15-50 micrometers. Moreover, as the curing conditions for the adhesive layer, after pressure bonding at a pressure of 0.01 to 10 MPa, particularly 0.1 to 2 MPa, a temperature of 100 to 200 ° C., particularly 120 to 180 ° C., for 30 minutes to 5 hours, particularly 1 to It is preferable to cure in 5 hours.

  The cured adhesive layer preferably has a low modulus of elasticity to provide a highly reliable semiconductor device. For example, the Young's modulus measured using a dynamic viscoelasticity measuring device is preferably 250 MPa or less at room temperature, and preferably 30 MPa or less at a high temperature, for example, a reflow temperature (240 to 270 ° C.).

  The adhesive composition of the present invention can be used not only in the production of electronic parts such as semiconductor devices but also in various productions including an adhesion process, for example, the production of LED parts, sensors, liquid crystal parts and the like.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, this invention is not limited to these Examples.

Synthesis of polyimide resin [Synthesis Example 1]
To a 1 L separable flask equipped with a 25 ml water meter with a cock connected to a reflux condenser, a thermometer and a stirrer was added 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride 32.2. Part by mass and 370 parts by mass of N-methylpyrrolidone as a solvent were charged and stirred to disperse the acid anhydride.
In the dispersion, the following formula

で示される、珪素原子に結合した全有機置換基の２３．１モル％のフェニル基を含有するフェニルメチルジアミノポリシロキサン（以後、「ジアミノシロキサン−１」という）１３５．７６質量部（上式においてｎおよびｐはある範囲の整数であり、その平均が、該フェニルメチルジアミノポリシロキサンのアミン当量が６７８．８となるような大きさである）をＮ−メチルピロリドン１３０質量部に分散させた溶液を滴下して、室温にて１６時間撹拌反応させることにより、アミック酸オリゴマーを合成した。該アミック酸オリゴマー溶液に、トルエン８０ｍｌを投入してから温度を上げ、約１８０℃で４時間還流させた。水分定量受器に所定量の水がたまっていること、水の流出が見られなくなっていることを確認し、水分定量受器にたまっている流出液を除去しながら、１８０℃でトルエンを除去した。反応終了後、大過剰のメタノール中に、得られた反応液を滴下してポリマーを析出させ、減圧乾燥してポリイミドシリコーン樹脂−１を得た。

135.76 parts by weight of phenylmethyldiaminopolysiloxane (hereinafter referred to as “diaminosiloxane-1”) containing 23.1 mol% of phenyl groups of all organic substituents bonded to silicon atoms n and p are integers within a certain range, and the average thereof is a size such that the amine equivalent of the phenylmethyldiaminopolysiloxane is 678.8). A solution in which 130 parts by mass of N-methylpyrrolidone is dispersed Was added dropwise and reacted at room temperature for 16 hours to synthesize an amic acid oligomer. To the amic acid oligomer solution, 80 ml of toluene was added, and then the temperature was raised and refluxed at about 180 ° C. for 4 hours. After confirming that a predetermined amount of water has accumulated in the moisture meter and that no water has flowed out, remove toluene at 180 ° C while removing the effluent accumulated in the meter. did. After completion of the reaction, the obtained reaction solution was dropped into a large excess of methanol to precipitate a polymer, and dried under reduced pressure to obtain polyimide silicone resin-1.

When the infrared absorption spectrum of the obtained resin was measured, absorption based on polyamic acid indicating that there was an unreacted functional group did not appear, and absorption based on an imide group was confirmed at 1780 cm ⁻¹ and 1720 cm ⁻¹ . It was 54,000 when the weight average molecular weight (polystyrene conversion) of this resin was measured by the gel permeation chromatography (GPC) which uses tetrahydrofuran as a solvent. This polyimide resin contains 80% by mass of phenylmethylpolysiloxane residues.

[Synthesis Example 2]
In Synthesis Example 1, 21.8 parts by mass of pyromellitic anhydride was used instead of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and 470 parts by mass of N-methylpyrrolidone was used in total. Obtained polyimide silicone resin-2 according to Synthesis Example 1. The molecular weight was 48,000. This polyimide resin contains 86 mass% of phenylmethylpolysiloxane residues.

[Synthesis Example 3]
In Synthesis Example 1, 35.8 parts by mass of bis (3,4-dicarboxyphenyl) sulfone dianhydride was used instead of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and diaminosiloxane was used. In place of -1, phenylmethyldiaminopolysiloxane having the formula shown in Synthesis Example 1 and containing 18.2 mol% of phenyl groups of all organic substituents bonded to silicon atoms (hereinafter “diaminosiloxane- 2 ”. Amine equivalent: 1112.2) 120.12 parts by weight are used together with 18.88 parts by weight of BAPP (2,2-bis [4- (4-aminophenoxy) phenyl] propane) as the other diamine. And according to the synthesis example 1 except having used 525 mass parts of N-methylpyrrolidone in total, the polyimide silicone resin-3 was obtained. The molecular weight was 52,000. This polyimide resin contains 69% by mass of phenylmethylpolysiloxane residues.

[Synthesis Example 4]
In Synthesis Example 1, 21.8 parts by mass of pyromellitic anhydride was used in place of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and Synthesis Example 1 was used instead of diaminosiloxane-1. Phenylmethyldiaminopolysiloxane having the formula shown and containing 31.3 mol% phenyl groups of all organic substituents bonded to silicon atoms (hereinafter referred to as “diaminosiloxane-3”; amine equivalent: 915.2) ) 164.75 parts by mass are used together with 2.16 parts by mass of an aromatic diamine diamine having a phenolic hydroxyl group represented by the following formula as another diamine, and 565 parts by mass of N-methylpyrrolidone is used. Except for the above, polyimide silicone resin-4 was obtained according to Synthesis Example 1. The molecular weight was 44,000. This polyimide resin contains 87 mass% of phenylmethylpolysiloxane residues.

[Comparative Synthesis Example 1]
In Synthesis Example 1, instead of diaminosiloxane-1, dimethyldiaminopolysiloxane represented by the following formula, in which all organic substituents bonded to silicon atoms are all methyl groups except aminopropyl groups (hereinafter referred to as “diaminosiloxane- 4 ”. Amine equivalent: 605.2.) Polyimide silicone resin-5 according to Synthesis Example 1 except that 121.05 parts by mass and a total of 460 parts by mass of N-methylpyrrolidone were used. Got. The molecular weight was 52,000. This polyimide resin contains 79% by mass of dimethylpolysiloxane residues.

[Comparative Synthesis Example 2]
In Synthesis Example 1, instead of diaminosiloxane-1, phenylmethyldiaminopolysiloxane having the formula shown in Synthesis Example 1 and containing 10 mol% of phenyl groups of all organic substituents bonded to silicon atoms Polyamine according to Synthesis Example 1 except that 96.45 parts by mass of amine equivalent: 482.2) and 370.5 parts by mass of N-methylpyrrolidone in total were used. Silicone resin-6 was obtained. The molecular weight was 57,000. This polyimide resin contains 76% by mass of dimethylpolysiloxane residues.

[Comparative Synthesis Example 3]
In Synthesis Example 1, 35.8 parts by mass of bis (3,4-dicarboxyphenyl) sulfone dianhydride was used instead of 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, and diaminosiloxane was used. -1 is used at 61.09 parts by mass, and BAPP (2,2-bis [4- (4-aminophenoxy) phenyl] propane) as another diamine is used at 22.58 parts by mass, and N-methylpyrrolidone is used. A polyimide silicone resin-7 was obtained in the same manner as in Synthesis Example 1 except that 360 parts by mass was used. The molecular weight was 54,000. This polyimide resin contains 51% by mass of dimethylpolysiloxane residues.

Preparation of polyimide resin solution 50 parts by mass of the polyimide resins 1 to 4 obtained in Synthesis Examples 1 to 4 and the polyimide resins 5 to 7 obtained in Comparative Synthesis Examples 1 to 3, respectively, 50 parts by mass of cyclohexanone To obtain a polyimide resin solution.

Preparation of adhesive composition (Examples 1-5, Reference Examples 1-3)
To each polyimide resin solution, the amount of epoxy resin, catalyst, curing agent, silica, and composite silicone rubber fine particles shown in Table 1 below, and cyclohexanone in an amount that makes the solid content concentration of the resin composition 40% by mass are added, -It mixed with the revolution type mixer (made by Shinki Co., Ltd.), and prepared the adhesive composition. The stability of each obtained adhesive composition was evaluated according to the following method (1).

(1) Stability over time of adhesive composition Each adhesive composition obtained above is allowed to stand for 24 hours and visually observed for the absence of separation or the like, and no phase separation or the like is observed. Evaluation was made as ○, and the case where phase separation was observed was evaluated as ×. The results are shown in Table 1.

  Next, each adhesive composition that was allowed to stand for 24 hours was applied onto a PET film having a thickness of 50 μm coated with a fluorine-based silicone release agent, followed by heating and drying at 120 ° C. for 10 minutes, and adhesion having a thickness of about 25 μm. An adhesive film with a layer was prepared. About the obtained adhesive film, the test of following (2)-(6) was done. The results are shown in Table 1.

(2) Surface state of adhesive layer The surface of the adhesive layer of each of the obtained films was visually observed, and the surface having a smooth surface was evaluated as ◯, and the surface with unevenness was observed as ×.

(3) Young's modulus Each of the adhesive films obtained above was cured by heating at 175 ° C. for 2 hours, and the resulting 8 adhesive layers were thermally laminated at 90 ° C. to a thickness of 200 μm. This was cut into a size of 40 mm × 10 mm × 200 μm to obtain a test piece. The Young's modulus of this test piece was measured using a dynamic viscoelasticity measuring device in a tensile mode under conditions of a distance between chucks of 10 mm, measurement temperatures of 25 ° C. and 250 ° C., and a measurement frequency of 1 Hz.

(4) Glass transition point and linear expansion coefficient Each of the adhesive films obtained above was cured by heating at 175 ° C. for 2 hours, and the resulting 8 adhesive layers were thermally laminated at 90 ° C. to a thickness of 200 μm. I made it. This was cut into a size of 20 mm × 5 mm × 200 μm to obtain a test piece. The glass transition point and the linear expansion coefficient (α1 and α2) of this test piece were measured using a thermomechanical measuring device TMA-2000 (manufactured by ULVAC-RIKO) in a tension mode, a distance between chucks of 15 mm, a measurement temperature of −60 to 300 ° C., The measurement was performed under conditions of a heating rate of 5 ° C./min and a measurement load of 3 g. In the linear expansion coefficient, α1 is a value in the temperature range below the glass transition point (in the case where there are two, the higher glass transition point), and α2 is a value in the temperature range above the glass transition point. It is.

(5) Adhesion test (initial)
A silicon wafer having a thickness of 450 μm was diced into 2 mm × 2 mm chips, and then the adhesive film prepared above was thermocompression bonded to the back surface of the silicon chips at 100 ° C. and cut into chip shapes. After the silicon chip with the adhesive film is taken out and the PET film is peeled off, the chip is bonded onto the BT substrate and the silicon substrate on which a 10 mm × 10 mm resist AUS303 (manufactured by Unitechno Co., Ltd.) is applied and cured. Were placed in contact with each other and fixed by thermocompression bonding for 2 seconds under the conditions of 150 ° C. and 0.1 MPa. Subsequently, it heated at 175 degreeC for 2 hours, the adhesive layer was hardened, and the test piece was produced. The shear adhesive strength at 260 ° C. was measured with a bond tester (manufactured by DAGE, 4000PXY).

(6) Adhesion test after wet heat The test piece prepared in the above (5) was held for 168 hours under the condition of 85 ° C./60% RH, and then passed through a reflow furnace at 260 ° C. three times. ), And the shear adhesive strength at 260 ° C. was measured.

In Table 1, all compounding amounts are solid contents. Moreover, the used resin etc. are as follows.
Resins used, etc. RE-310S: Liquid epoxy resin, Nippon Kayaku Co., Ltd. EPPN-501H: Epoxy resin, liquefaction temperature 51-57 ° C., Nippon Kayaku Co., Ltd. Epicoat 834: Epoxy resin, semi-solid, softening temperature 64 ° C. Japan Epoxy Resin H-4: Epoxy resin curing agent, Meiwa Kasei Kogyo 2PHZ: Epoxy resin curing catalyst, 2-phenyl-4,5-dihydroxymethylimidazole, Shikoku Kasei Dicyandiamide: Epoxy resin curing catalyst, Japan Epoxy resin silica particle-1: Musil-120A, surface trimethylsilyl group-treated silica, specific surface area 200 m ² / g, Shin-Etsu Chemical Co., Ltd. silica particle-2: SE-2050, spherical silica, manufactured by Admatechs, average particle Diameter 0.5μm
Composite silicone rubber fine particles: X-52-7030, average particle size 0.7 μm, manufactured by Shin-Etsu Chemical Co., Ltd.

   As can be seen from Table 1, the cured product obtained from the composition of the present invention is a composition compared to a composition (Reference Examples 1 and 2) comprising a polyimide silicone resin containing a polysiloxane skeleton having a low phenyl group content. The Young's modulus is remarkably lower than that of a composition (Reference Example 3) comprising a polyimide silicone resin having excellent stability over time, giving a smooth surface coating film, and having a low polysiloxane skeleton content. . In addition, about the composition of the reference examples 1 and 2, since the surface of the contact bonding layer was not favorable, tests (3)-(6) could not be performed. In addition, the composition of Reference Example 3 had a very high Young's modulus at 25 ° C. and was not likely to be put to practical use at low temperatures.

   The adhesive composition of the present invention is suitably used for semiconductor die bonding. Further, it is suitable as an adhesive in applications requiring low elastic modulus and high heat resistance.

Claims (8)

(A) 15 mol% or more of all organic substituents containing a diorganopolysiloxane residue bonded to the silicon atom of the residue are phenyl groups, and the mass of the diorganopolysiloxane residue is 60% of the resin. 100 parts by mass of polyimide resin that is at least mass%,
(B) 5-100 mass parts of epoxy resin,
(C) 0-100 mass parts of epoxy resin curing agent,
(D) an effective amount of an epoxy resin curing catalyst,
An adhesive composition comprising: The adhesive composition according to claim 1, wherein the diorganopolysiloxane residue has the following formula (1).

(In the formula, R ¹ is a divalent organic group having 3 to 9 carbon atoms, and R ^{2 to} R ⁶ are monovalent carbon atoms that do not contain an unsubstituted or substituted aromatic ring having 1 to 8 carbon atoms. It is a hydrogen group, and n, m and p are 0 or an integer of 1 or more, m + p is an integer of 1 or more, and n + m + p is an integer of 1 to 100.) The adhesive composition according to claim 1 or 2, wherein the epoxy resin as component (B) is a compound having an aromatic compound residue. The adhesive composition according to any one of claims 1 to 3, wherein the epoxy resin as the component (B) includes an epoxy resin having a softening point of 80 ° C or less as measured by the ring and ball method JIS-K7234. The adhesive composition according to any one of claims 1 to 4, wherein the epoxy resin as component (B) contains at least one epoxy resin that is liquid at 25 ° C. The adhesive composition according to any one of claims 1 to 5, further comprising an inorganic filler. The adhesive composition according to claim 6, wherein the inorganic filler is silica particles and / or composite silicone rubber fine particles. The adhesive film provided with the contact bonding layer which consists of an adhesive composition of any one of Claims 1-7.