JP2012072305A - Resin paste composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin paste composition curable at 125°C or lower, excellent in bonding strength and free from bleeding out, and good in workability.SOLUTION: The resin paste composition includes: (A) a compound selected from an acrylic ester compound and a methacrylic ester compound; (B) a peroxide represented by general formula (1) and having a 10 hour half-life period temperature of 60-80°C; (C) a flexibilizer; and (D) a filler containing a non-spherical filler and a spherical filler. In the formula, R represents a 1-10C alkyl group or a 2-acylperoxypropyl-2-yl alkylene group; and Rrepresents a 3-10C alkyl group.

Description

  The present invention relates to a resin paste composition suitable for bonding a semiconductor element such as an IC or LSI to a lead frame, a glass epoxy wiring board or the like, and a semiconductor device using the resin paste composition.

  Conventionally, Au-Si eutectic, solder, resin paste compositions, etc. are known as semiconductor die bonding materials, but resin paste compositions are widely used from the viewpoint of workability and cost (for example, Patent Document 1).

  Currently, a package having a structure as shown in FIG. 1 called BGA (Ball Grid Array) is widely used as a semiconductor package. In this package, a semiconductor element is bonded onto a substrate using a die bonding material, and the electrode pad on the semiconductor element and the wire bond connection point on the substrate are wire bonded with an Au wire or the like. In recent years, with the miniaturization of a semiconductor package represented by BGA, the distance between a semiconductor element and a wire bond connection point on a substrate has been shortened. In such a case, when the wire bond connection point existing on the substrate is close to the chip, for example, when it is 500 μm or less, particularly 300 μm or less, the wire is oozed out by a die bonding material (resin paste) called bleed out. There are cases where poor workability occurs during bonding. Furthermore, in the MAP (Mold Array Package) type, since a plurality of packages exist on one substrate, the substrate area is large, and the room temperature storage time during assembly is increased, so that bleedout of the die bonding material is likely to occur. May be.

  On the other hand, there is an increasing demand for thinning semiconductor packages, and in recent years, thinning of semiconductor elements themselves is also progressing. As a result, in the range of 150 to 200 ° C., which is a conventional curing temperature, the warpage of the semiconductor element is increased after the resin paste is cured, and the semiconductor element may be cracked. In addition to the semiconductor elements, the thickness of the substrate is similarly reduced, and at the conventional curing temperature, after the resin paste is cured, warping of the assembled package becomes large, and the subsequent wire bonding process and sealing are performed. The assembly workability problem occurs in the stop process. The reason for this is that the larger the semiconductor element, the greater the warpage of the semiconductor element and the more likely to crack, and the thinner the substrate, the more susceptible to shrinkage due to the resin paste curing process. .

  In order to reduce the above effects, a resin paste that can be cured at a low temperature (125 ° C. or less) and has good workability without causing bleed-out has been demanded in recent years.

JP 2004-168933 A

  An object of this invention is to provide the resin paste composition which can be hardened | cured at low temperature (125 degrees C or less), and is excellent in workability | operativity, without producing bleed-out.

The present invention includes (A) an acrylic ester compound or a methacrylic ester compound, (B) a peroxide (radical initiator) represented by the following general formula (1), (C) a flexible material, (D) The present invention relates to a resin paste composition in which a filler containing a non-spherical filler and a spherical filler is uniformly dispersed. The present invention also relates to a semiconductor device in which a semiconductor element is bonded to a support member using this resin paste composition and then sealed.
(In the formula (1), R represents an alkyl group having 1 to 10 carbon atoms or an organic group represented by the following general formula (2), and R ¹ represents an alkyl group having 3 to 10 carbon atoms.)
(In Formula (2), R ² represents an alkylene group having 1 to 6 carbon atoms, and R ³ represents an alkyl group having 3 to 10 carbon atoms.)

  That is, the resin paste composition of the present invention can prevent the occurrence of bleed-out during curing by curing before the bleed-out by lowering the reaction start temperature of the resin paste composition, As a result, workability failure during wire bonding can be reduced.

  Further, by lowering the reaction start temperature of the resin paste composition of the present invention, low temperature (125 ° C. or lower) curing becomes possible, and stress generated due to the difference in linear expansion coefficient between the semiconductor element and the substrate due to low temperature curing. Can be reduced. As a result, cracks in the semiconductor element after curing can be suppressed, warpage of the semiconductor element and the substrate can be reduced, and occurrence of reflow cracks during solder reflow can be reduced.

  Furthermore, since the resin paste composition of the present invention contains a spherical filler, the specific surface area per unit part by weight becomes small, so that the viscosity of the resin paste can be reduced, resulting in improved workability. In addition, the adhesive strength is high, the occurrence of bleed-out during the assembly of the package can be prevented, and the productivity and reliability can be increased. On the other hand, in general, when the resin component of the resin paste is reduced in viscosity, since the resin component is more likely to bleed out (bleed out), the resin paste composition of the present invention is filled. It is designed to reduce the viscosity with a filler used as an agent, thereby preventing bleeding out before curing.

  The resin paste composition of the present invention can be cured at a low temperature when used as a die bonding material for a semiconductor device, and can prevent bleeding out. As a result, workability failure at the time of wire bonding can be prevented, and the warp of the semiconductor element and the substrate can be reduced without voids. In addition, the viscosity of the resin paste can be reduced by adding a spherical filler, etc., and the viscosity can be adjusted, which can prevent the occurrence of bleed-out during the improvement of productivity and adhesive strength and assembly, Reliability as a semiconductor device can be improved.

The schematic diagram which shows the structure of the cross section of BGA in which the resin paste composition (die-bonding material) of this invention is used suitably. The electron micrograph which shows the external appearance of the spherical filler "SO-E3" used by this invention. The electron micrograph which shows the external appearance of the non-spherical (scale-like) filler "HP-P1-HJ" used by this invention. The electron micrograph which shows the external appearance of the non-spherical (massive) filler "R972" used by this invention.

  The present invention relates to (A) a compound selected from an acrylic ester compound and a methacrylic ester compound, a peroxide represented by the general formula (1) and having a 10-hour half-life temperature of 60 to 80 ° C., (C And (D) a resin paste composition comprising a filler containing a non-spherical filler and a spherical filler.

  The acrylic acid ester compound or methacrylic acid ester compound as the component (A) used in the present invention is a compound having one or more acryloyloxy groups or methacryloyloxy groups in one molecule. For example, the following general formula (I ) To (IX) can be used.

(1) General formula (I)
[Wherein, R ¹ represents hydrogen or a methyl group, and R ² represents a divalent aliphatic or cyclic hydrocarbon structure having 1 to 100 carbon atoms, preferably 1 to 36 carbon atoms. ]
A compound represented by

Examples of the compound represented by the general formula (I) include methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, t-butyl acrylate, amyl acrylate, isoamyl acrylate, hexyl acrylate, heptyl acrylate, octyl Acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, isodecyl acrylate, lauryl acrylate, tridecyl acrylate, hexadecyl acrylate, stearyl acrylate, isostearyl acrylate, cyclohexyl acrylate, isobornyl acrylate, tricyclo [5.2.1 .0 ^2,6] decyl acrylate, 2- (tricyclo) [5.2.1. ^2,6] dec-3-ene -8 or 9-yl - acrylate compounds such as oxyethyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, n- butyl methacrylate, isobutyl methacrylate, t- butyl methacrylate, amyl Methacrylate, isoamyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, nonyl methacrylate, decyl methacrylate, isodecyl methacrylate, lauryl methacrylate, tridecyl methacrylate, hexadecyl methacrylate, stearyl methacrylate, isostearyl methacrylate, cyclohexyl methacrylate, Isobornylmetac Rate, tricyclo [5.2.1.0 ^{2, 6]} decyl methacrylate, 2- (tricyclo) [5.2.1.0 ^2,6] dec-3-ene -8 or 9-yl - methacrylate And other methacrylate compounds.

(2) General formula (II)
[Wherein, R ¹ and R ² each represent the same as above. ]
A compound represented by

  Examples of the compound represented by the general formula (II) include acrylate compounds such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and dimer diol monoacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimer diol monomethacrylate, and the like. Of methacrylate compounds.

(3) General formula (III)
[Wherein R ¹ represents the above, R ³ represents hydrogen, a methyl group or a phenoxymethyl group, R ⁴ represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a phenyl group or a benzoyl group, n Represents an integer of 1 to 50. ]
A compound represented by

  Examples of the compound represented by the general formula (III) include diethylene glycol acrylate, polyethylene glycol acrylate, polypropylene glycol acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, methoxydiethylene glycol acrylate, methoxypolyethylene glycol acrylate, Acrylate compounds such as 2-phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, phenoxy polyethylene glycol acrylate, 2-benzoyloxyethyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, diethylene glycol methacrylate, polyethylene glycol methacrylate, polypropylene glycol Chryrate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethyl methacrylate, methoxydiethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, 2-phenoxyethyl methacrylate, phenoxydiethylene glycol methacrylate, phenoxypolyethylene glycol methacrylate, 2-benzoyloxyethyl methacrylate And methacrylate compounds such as 2-hydroxy-3-phenoxypropyl methacrylate.

(4) General formula (IV)
[Wherein R ¹ represents the above, R ⁵ represents a phenyl group, a nitrile group, —Si (OR ⁶ ) ₃ (R ⁶ represents an alkyl group having 1 to ⁶ carbon atoms) or a group of the following formula:

(R ⁷ , R ⁸ and R ⁹ each independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms, R ¹⁰ represents hydrogen, an alkyl group having 1 to 6 carbon atoms or a phenyl group), m represents Represents the number 0, 1, 2, or 3. ]
A compound represented by

  Examples of the compound represented by the general formula (IV) include benzyl acrylate, 2-cyanoethyl acrylate, γ-acryloxypropyltrimethoxysilane, glycidyl acrylate, tetrahydrofurfuryl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopenta Nyl acrylate, dicyclopentenyl acrylate, tetrahydropyranyl acrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate, 1,2,2,6,6-pentamethylpiperidinyl acrylate, 2,2,6 , 6-tetramethylpiperidinyl acrylate, acryloxyethyl phosphate, acryloxyethyl phenyl acid phosphate, β-acryloyloxyethyl hydrogen phthalate, β-acryloyl o Acrylate compounds such as ciethyl hydrogen succinate, benzyl methacrylate, 2-cyanoethyl methacrylate, γ-methacryloxypropyltrimethoxysilane, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, tetrahydropyranyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, 1,2,2,6,6-pentamethylpiperidinyl methacrylate, 2,2,6,6-tetramethylpiperidinyl methacrylate, methacrylates such as methacryloxyethyl phosphate, methacryloxyethyl phenyl acid phosphate, β-methacryloyl Such as oxyethyl hydrogen phthalate and β-methacryloyloxyethyl hydrogen succinate. There are tacrylate compounds.

(5) General formula (V)
[Wherein, R ¹ and R ² each represent the same as above. ]
A compound represented by

  Examples of the compound represented by the general formula (V) include ethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, and 1,3-butanediol. Diacrylate compounds such as diacrylate, neopentyl glycol diacrylate, dimer diol diacrylate, dimethylol tricyclodecane diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,3-butanediol dimethacrylate, neopentyl glycol dimethacrylate, dimer diol dimethacrylate, dimethylol tricyclodecanedi There are dimethacrylate compounds such as methacrylate.

(6) General formula (VI)
[Wherein, R ¹ , R ³ and n each represent the same as above, provided that n is not 1 when R ³ is hydrogen or a methyl group. ]
A compound represented by

  Examples of the compound represented by the general formula (VI) include diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate and the like, diethylene glycol There are dimethacrylate compounds such as dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, and polypropylene glycol dimethacrylate.

(7) General formula (VII)
[Wherein, R ¹ represents the above, and R ¹¹ and R ¹² each independently represent hydrogen or a methyl group. ]
A compound represented by

  Examples of the compound represented by the general formula (VII) include a reaction product of 1 mol of bisphenol A, bisphenol F or bisphenol AD and 2 mol of glycidyl acrylate, a reaction product of 1 mol of bisphenol A, bisphenol F or bisphenol AD and 2 mol of glycidyl methacrylate, and the like. There is.

(8) General formula (VIII)
[Wherein, R ¹ , R ¹¹ and R ¹² each represent the same as above, R ¹³ and R ¹⁴ each independently represent hydrogen or a methyl group, and p and q each independently represent an integer of 1 to 20. ]
A compound represented by

  Examples of the compound represented by the general formula (VIII) include diacrylate of bisphenol A, bisphenol F or polyethylene oxide adduct of bisphenol AD, diacrylate of bisphenol A, bisphenol F or polypropylene oxide adduct of bisphenol AD, bisphenol A, bisphenol. Examples include dimethacrylate of polyethylene oxide adduct of F or bisphenol AD, dimethacrylate of polypropylene oxide adduct of bisphenol A, bisphenol F or bisphenol AD.

(9) General formula (IX)
[Wherein, R ¹ represents the above, R ¹⁵ , R ¹⁶ , R ¹⁷ and R ¹⁸ each independently represent hydrogen or a methyl group, and x represents an integer of 1-20. ]
A compound represented by

  Examples of the compound represented by the general formula (IX) include bis (acryloxypropyl) polydimethylsiloxane, bis (acryloxypropyl) methylsiloxane-dimethylsiloxane copolymer, bis (methacryloxypropyl) polydimethylsiloxane, and bis (methacryloxypropyl). ) Methylsiloxane-dimethylsiloxane copolymer.

(A) As an acrylic ester compound or methacrylic ester compound of a component, said compound can be used individually or in combination of 2 or more types.
Among them, monofunctional acrylate compounds are preferred for use because they are harder to harden than bifunctional or higher acrylate compounds, chip warpage can be reduced, and the viscosity of the resin paste composition can be easily reduced. .

The peroxide represented by the following general formula (1) of the component (B) used in the present invention has a 10-hour half-life temperature of 60 to 80 ° C. from the viewpoint of curability and viscosity stability of the resin paste composition. It is preferable that
General formula (1)
(In the formula (1), R represents an alkyl group having 1 to 10 carbon atoms or an organic group represented by the following general formula (2), and R ¹ represents an alkyl group having 3 to 10 carbon atoms.)
(In Formula (2), R ² represents an alkylene group having 1 to 6 carbon atoms, and R ³ represents an alkyl group having 3 to 10 carbon atoms.)

Here, the half-life is indicated by the time required for the organic peroxide at a constant temperature to decompose and the amount of active oxygen to be halved.
The half-life can be measured, for example, as follows.

  First, a solution that is relatively inert to radicals, for example, benzene is mainly used to prepare an organic peroxide solution having a concentration of 0.1 mol / L, which is then sealed in a glass tube subjected to nitrogen substitution. Further, it is immersed in a thermostat set at a predetermined temperature and thermally decomposed.

In general, decomposition of an organic peroxide can be treated approximately as a primary reaction. Therefore, assuming that the concentration of organic peroxide x, decomposition rate constant k, time t, and initial organic peroxide concentration a
dx / dt = k (ax) (i)
ln a / (ax) = kt (ii)
Since the half-life is the time until the organic peroxide concentration is reduced to half of the initial value due to decomposition, the half-life is indicated by t _1/2 , and a / 2 is substituted for x in the formula (ii)
kt _1/2 = ln2 (iii)
Therefore, thermal decomposition is performed at a certain temperature, k is obtained from the slope of the obtained straight line, and the half-life (t _1/2 ) at that temperature can be obtained from equation (iii).

  Specific examples of the radical initiator include perbutyl O (t-butylperoxy 2-ethylhexanoate), perhexyl O (t-hexylperoxy 2-ethylhexanoate), perhexa25O (2,5-dimethyl- 2,5-bis (2-ethylhexanoylperoxy) hexane) and the like.

  (B) As for the compounding quantity of the peroxide (radical initiator) of a component, 1-10 mass parts is preferable with respect to 100 mass parts of total amounts of (A) component, and 2-5 mass parts is especially preferable. If the blending ratio is less than 0.1 parts by mass, the curability tends to decrease, and if it exceeds 10 parts by mass, the volatile matter tends to increase and voids called voids tend to occur in the cured product. is there.

  As the flexible material of the component (C) used in the present invention, various liquid rubbers and thermoplastic resins are used. For example, polybutadiene, maleated polybutadiene, acrylonitrile butadiene rubber, carboxy terminal acrylonitrile butadiene rubber, amino terminal acrylonitrile. Examples thereof include liquid rubbers such as butadiene rubber, vinyl-terminated acrylonitrile butadiene rubber and styrene butadiene rubber, and thermoplastic resins such as polyvinyl acetate, polymethyl acrylate, ε-caprolactone-modified polyester, phenoxy resin, and polyimide.

  The liquid rubber preferably has a number average molecular weight of 500 to 10,000, more preferably 1,000 to 5,000. If the molecular weight is too small, the flexibility effect tends to be inferior. If the molecular weight is too large, the viscosity of the resin paste composition tends to increase and the workability tends to be inferior. The number average molecular weight can be measured by a value measured by a vapor pressure osmosis method or a GPC method, but is preferably based on a value measured by a GPC method.

  The thermoplastic resin preferably has a number average molecular weight of 10,000 to 300,000, more preferably 20,000 to 200,000. If the molecular weight is too small, the flexibility effect tends to be inferior. If the molecular weight is too large, the viscosity of the resin paste composition tends to increase and the workability tends to be inferior.

  Moreover, as a compounding quantity of a flexible material, it is preferable to use 10-100 mass parts with respect to 100 mass parts of (A) component, and it is more preferable to use 30-80 mass parts. If the blending amount is less than 10 parts by mass, the flexibility effect is inferior, and if it exceeds 100 parts by mass, the viscosity increases and the workability of the resin paste composition tends to decrease.

  The filler of component (D) used in the present invention is a combination of a non-spherical filler and a spherical filler. As these fillers, both non-spherical fillers and spherical fillers are not particularly limited as long as the average particle diameter is less than 10 μm, and various types are used. For example, silicon oxide, boron nitride, aluminum oxide, boron Insulating powders such as aluminum oxide, aluminum nitride, silicon nitride, and silicon carbide are preferred. When the average particle size of the filler is 10 μm or more, the paste uniformity and various physical properties are deteriorated. A preferable average particle diameter is 0.5-7 micrometers, and it is more preferable that it is 0.5-5 micrometers.

  As the spherical filler, those having a true spherical shape, an elliptical spherical shape and the like are used, but those having a shape having a smooth surface as close as possible to a true spherical shape are preferable. Aspect ratio [In the electron micrograph, the major axis of each particle (when one particle is sandwiched between two parallel tangents, the longest distance is defined as the major axis) and the minor axis (the two parallel The ratio of the major axis / minor axis) is defined as the distance between two tangents in the direction orthogonal to the tangent to be defined. It measures about 20 particle | grains from an electron micrograph, and makes it the average value. ] Is preferably 1 to 2, more preferably 1 to 1.5, still more preferably 1 to 1.2, and particularly preferably 1 to 1.1.

  On the other hand, as the non-spherical filler, the shape is scale-like, cocoon-like (for example, potato-like round shape, a shape having a relatively smooth curved surface with unevenness), a lump-like shape (for example, Polyhedron-like shapes, rugged corners and irregularities, or flat surfaces but overall lump particles), dendritic, plate-like, spherical primary fine particles agglomerated Examples of the shape include secondary particle lumps, and the like is preferable in which lumps, scales, bowls, and spherical fine particles aggregate to form secondary particles. The filler has an aspect ratio of preferably 1 to 100, and more preferably 1 to 10.

  In particular, as a non-spherical filler, the resin paste composition can have a low viscosity by combining a spherical filler with a shape in which primary particles in the form of cocoons, lumps and spheres aggregate to form secondary particles. The combination of the non-spherical filler and the spherical filler is preferably a combination of 10 to 40% by weight, more preferably 10 to 30% by weight of the spherical filler with respect to 100% by weight of component (D).

  Moreover, the compounding quantity of the whole filler containing the non-spherical filler and spherical filler of (D) component is not specifically limited, However, 5 to 50 weight% is preferable with respect to the resin paste composition total amount, and 10 to 40 weight% is more. preferable. If the blending amount is less than 5% by weight, the adhesive strength during heating tends to decrease, and if it exceeds 50% by weight, the viscosity increases, and the workability during production and the coating workability during use decrease. Tend to.

  Moreover, an epoxy resin and an epoxy resin curing agent can be added to the resin paste composition of the present invention in order to improve adhesive strength and the like. The epoxy resin is not particularly limited as long as it is a compound having two or more epoxy groups in one molecule. For example, bisphenol A type epoxy resin [AER-X8501 (Asahi Kasei Kogyo Co., Ltd., trade name), R- 301 (Oilized Shell Epoxy Co., Ltd., trade name), YL-980 (Oilized Shell Epoxy Co., Ltd., trade name)], Bisphenol F type epoxy resin [YDF-170 (Toto Kasei Co., Ltd., trade name) ], Bisphenol AD type epoxy resin [R-1710 (Mitsui Chemicals, Inc., trade name)], phenol novolak type epoxy resin [N-730S (DIC Corporation, trade name), Quatrex-2010 (Dow Chemical) Company, product name)], cresol novolac epoxy resin [YDCN-702S (Toto Kasei Co., Ltd., product name), EOCN-100 (Japan) Kayaku Co., Ltd., trade name)], polyfunctional epoxy resin [EPPN-501 (Nippon Kayaku Co., Ltd., trade name), TACTIX-742 (Dow Chemical Co., trade name), VG-3010 (Mitsui Chemicals) (Trade name), 1032S (Oilized Shell Epoxy Co., Ltd., trade name)], epoxy resin having a naphthalene skeleton [HP-4032 (DIC Corporation, trade name)], alicyclic epoxy resin [ CEL-3000 (Daicel Chemical Industries, Ltd., trade name)], epoxidized polybutadiene [PB-3600 (Daicel Chemical Industries, Ltd. trade name), E-1000-6.5 (Nippon Petrochemical Co., Ltd., Commodity) Name)], amine type epoxy resin [ELM-100 (Sumitomo Chemical Co., Ltd., trade name), YH-434L (Toto Kasei Co., Ltd., trade name)], resorcinol type epoxy resin [Denacol EX- 01 (Nagase Kasei Kogyo Co., Ltd., trade name)], neopentyl glycol type epoxy resin [Denacol EX-211 (Nagase Kasei Kogyo Co., Ltd., trade name)], hexane diner glycol type epoxy resin [Denacol EX-212] (Nagase Kasei Kogyo Co., Ltd., trade name)], ethylene / propylene glycol type epoxy resin [Denacol EX-810, 811, 850, 851, 821, 830, 832, 841, 861 (Nagase Kasei Kogyo Co., Ltd., product) Name)], epoxy resin represented by the following general formula (XI) [E-XL-24, E-XL-3L (Mitsui Chemicals, Inc., trade name)]

[In formula, v represents the integer of 0-5. ]
Etc. Among these, bisphenol F type epoxy resin, epoxidized polybutadiene, and novolac type epoxy resin are preferable. These epoxy resins may be used individually by 1 type, and may be used in combination of 2 or more type.

  The epoxy resin preferably has a molecular weight or number average molecular weight of 160 to 3,000. The number average molecular weight is a value measured by gel permeation chromatography using a standard polystyrene calibration curve (hereinafter referred to as GPC method). Moreover, it is preferable that epoxy equivalent is 80-1000, and it is more preferable that it is 100-500. Moreover, it is preferable to use 1-100 mass parts of such an epoxy resin with respect to 100 mass parts of total amounts of (A) component, and it is more preferable to use 5-30 mass parts. If this amount is less than 1 part by mass or exceeds 100 parts by mass, the adhesive strength tends to decrease.

  Moreover, the compound [monofunctional epoxy compound (reactive diluent)] which has one epoxy group in 1 molecule as an epoxy resin may be included. Commercially available products of such monofunctional epoxy compounds include PGE (Nippon Kayaku Co., Ltd., trade name, phenylglycidyl ether), PP-101 (Toto Kasei Co., Ltd., trade name, alkylphenol monoglycidyl ether), ED. -502 (Asahi Denka Kogyo Co., Ltd., trade name, aliphatic monoglycidyl ether), ED-509 (Asahi Denka Kogyo Co., Ltd., trade name, alkylphenol monoglycidyl ether), YED-122 (Oilized Shell Epoxy Co., Ltd.) ), Trade name, alkylphenol monoglycidyl ether), KBM-403 (Shin-Etsu Chemical Co., Ltd., trade name, 3-glycidoxypropyltrimethoxysilane), TSL-8350, TSL-8355, TSL-9905 (Toshiba Silicone) Co., Ltd., trade name, 3-glycidoxypropyltrimethoxysilane, 3-g Sid propyl methyl dimethoxy silane, 1- (3-glycidoxypropyl) 1,1,3,3,3 pentamethyl disiloxane), and the like. The monofunctional epoxy compound is used in a range that does not impair the properties of the resin paste composition of the present invention, but is preferably used in an amount of 10 parts by mass or less with respect to 100 parts by mass of the total epoxy resin, and 1 to 5 masses It is preferably used in parts.

The epoxy resin curing agent is not particularly limited, but dicyandiamide, the following general formula (XII)
[Wherein, R ¹⁹ represents a divalent aromatic group such as an m-phenylene group or a p-phenylene group, or a linear or branched alkylene group having 2 to 12 carbon atoms. ]
A dibasic acid dihydrazide [ADH, PDH, SDH (all manufactured by Nippon Finechem Co., Ltd., trade name)], a microcapsule type curing agent composed of a reaction product of an epoxy resin and an amine compound [Novacure (Asahi Kasei Corporation) ), Trade name)] and the like. Moreover, these epoxy resin hardening | curing agents may be used individually by 1 type, and may be used in combination of 2 or more type. 0.1-50 mass parts is preferable with respect to 100 mass parts of epoxy resins, and, as for the compounding quantity of such an epoxy resin hardening | curing agent, 1-20 mass parts is more preferable. When the amount of the epoxy resin curing agent is less than 0.1 parts by mass, the curability tends to be inferior, and when it exceeds 50 parts by mass, the stability of the resin composition tends to deteriorate.

  Furthermore, a curing accelerator can be added to the resin paste composition of the present invention as necessary. Examples of the curing accelerator include organic boron salt compounds [EMZ · K, TPPK (trade name, manufactured by Hokuko Chemical Co., Ltd.)], tertiary amines or salts thereof [DBU, U-CAT102, 106, 830, 840. , 5002 (both are trade names of San Apro Co., Ltd.), etc.] and imidazoles [Cureazole, 2P4MHZ, C17Z, 2PZ-OK (both are trade names of Shikoku Kasei Co., Ltd.)] and the like. It is preferable that the compounding quantity of a hardening accelerator shall be normally 20 mass parts or less with respect to an epoxy resin. The hardening accelerator added as needed may be used individually by 1 type, and may be used in combination of multiple types of hardening accelerator suitably.

  A coupling agent can be added to the resin paste composition of the present invention. The coupling agent used in the present invention is not particularly limited, and various types such as a silane coupling agent, a titanate coupling agent, an aluminum coupling agent, a zirconate coupling agent, and a zircoaluminate coupling agent. Is used.

  Specific examples of the coupling agent include methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinyl-tris (2- Methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, methyltri (methacryloxyethoxy) silane, γ-acryloxypropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ- Aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (N- Nylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane, γ-anilinopropyltrimethoxysilane, γ-ureidopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, 3- (4,5-dihydroimidazolyl) propyl Triethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, γ-glycidoxypropylmethyldiisopropeno Xysilane, methyltriglycidoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylmethyldimethoxysilane, trimethylsilyl isocyanate, dimethylsilyliso Silane coupling agents such as anate, phenylsilyl triisocyanate, tetraisocyanate silane, methylsilyl triisocyanate, vinylsilyl triisocyanate, ethoxysilane triisocyanate, isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyro) Phosphate) titanate, tetraisopropyl bis (dioctyl phosphite) titanate, tetraoctyl bis (ditridecyl phosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) bis (di-tridecyl) phosphite titanate, bis (Dioctyl pyrophosphate) oxyacetate titanate, bis (dioctyl pyrophosphate) ) Ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylisostearoyl titanate, isopropyl (dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, isopropyl tri (N-aminoethylaminoethyl) titanate, dicumylphenyloxyacetate titanate, Titanate coupling agents such as diisostearoylethylene titanate, aluminum coupling agents such as acetoalkoxyaluminum diisopropionate, tetrapropyl zirconate, tetrabutyl zirconate, tetra (triethanolamine) zirconate, tetraisopropyl zirconate , Zirconium acetylacetonate acetylacetone zirconium butyrate, There are zirconate-based coupling agents such as stearic acid zirconium butyrate.

  0.1-20 mass parts is preferable with respect to 100 mass parts of total amounts of (A) component, and, as for the compounding quantity of a coupling agent, 1-15 mass parts is especially preferable. When the blending ratio is less than 0.1 parts by mass, the effect of improving the adhesive strength is inferior, and when it exceeds 20 parts by mass, the volatile matter increases and voids tend to occur in the cured product.

  The resin paste composition according to the present invention further includes a moisture absorbent such as calcium oxide and magnesium oxide, a fluorosurfactant, a nonionic surfactant, a wetting improver such as a higher fatty acid, silicone oil and the like as necessary. Solvents for viscosity adjustment, such as defoaming agents and ion trapping agents such as inorganic ion exchangers, can be added as appropriate, alone or in combination of several kinds. In addition, when adding a solvent, it is preferable to set it as 3 weight% or less from the point of a void.

  In order to produce the resin paste composition according to the present invention, (A) an acrylic ester compound or a methacrylic ester compound, (B) a peroxide represented by the general formula (1), and a 10-hour half-life temperature of 60 A compound which is ˜80 ° C., (C) a flexible material, (D) an inorganic filler containing a non-spherical filler and a spherical filler, together with various additives used as necessary, or batchwise or divided into a stirrer, If it is put into a device that is appropriately combined with a dispersing / dissolving device such as a raikai device, three rolls, planetary mixer, etc., it is heated and mixed, dissolved, pulverized and kneaded or dispersed as necessary to form a uniform paste. good.

  The resin paste composition of the present invention has a viscosity (for example, an EHD type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd.), a 3 ° cone rotor, 0.5 rpm, 5 rpm at 25 ° C. (Pa · s)). When measured, it is preferably 30 to 80 Pa · s, more preferably 40 to 60 Pa · s at 0.5 rpm. Moreover, it is preferable to set it as 10-30 Pa.s at 5 rpm, and it is more preferable to set it as 13-20 Pa.s. And thixotropy (viscosity of 0.5 rpm / 5 viscosity of 5 rpm) is preferably 3 or more.

  In the present invention, the semiconductor device can be further sealed by bonding the semiconductor element to the support member using the resin paste composition manufactured as described above.

  As support members, for example, lead frames such as 42 alloy lead frames and copper lead frames, glass epoxy substrates (substrates made of glass fiber reinforced epoxy resin), BT substrates (cyanate monomers and their oligomers and BT resins made of bismaleimide) Substrate), a substrate using a phenol resin, and the like.

  In order to adhere a semiconductor element to a support member such as a lead frame using the resin paste composition of the present invention, first, after applying the resin paste composition on the support member by a dispensing method, a screen printing method, a stamping method, It can be performed by pressure-bonding the semiconductor element and then heat-curing using a heating device such as an oven or a heat block. Furthermore, it can be set as the completed semiconductor device by sealing by a normal method after passing through a wire bonding process.

  Also, normally, when using an organic substrate, it absorbs moisture, and without drying, it evaporates due to the heat of curing of the resin-based paste and causes voids in the paste layer. Necessary. However, since the curing reaction of the resin paste starts at a low temperature in the present invention, a highly reliable semiconductor device can be assembled without generating voids without drying the substrate.

  As described above, the resin paste composition of the present invention can be cured at a low temperature and has no bleed-out. Therefore, the resin paste composition is particularly effective when a semiconductor element is bonded onto a BGA substrate.

  That is, as shown in FIG. 1, a semiconductor element 1 is mounted on a BGA substrate 2 and bonded by a die bonding material (resin paste) 4, and then an electrode 7 on the BGA substrate existing around the semiconductor element. In the semiconductor element package in which the electrode 6 on the semiconductor element is wire-bonded 5 with Au wire or the like, the effect is exhibited when used for bonding the BGA substrate 2 and the semiconductor element 1. When applied to a semiconductor package in which the distance between the side surface and the electrode 7 on the BGA substrate, that is, the distance between the semiconductor element and the pad is 500 μm or less, particularly 300 μm or less, there is no bleeding of the resin due to bleed-out during bonding. Die bonding material (resin paste) that improves the workability of wire bonding and bonds semiconductor elements and BGA substrates As the composition), it can be suitably used. Such a BGA type semiconductor device can be manufactured by performing wire bonding, sealing with a mold resin, and providing an external electrode of the solder ball 3.

  Moreover, it is preferable to heat-harden said resin paste composition at the temperature of 80-150 degreeC, Preferably it is 100-125 degreeC for 5 minutes-3 hours, Preferably it is 15 minutes-1.5 hours.

  EXAMPLES Next, although an Example demonstrates this invention in detail, this invention is not restrict | limited by this.

Examples 1 to 10 and Comparative Examples 11 to 13
The compounds used in Examples and Comparative Examples are illustrated below.
(1) Acrylic ester compound and methacrylic ester compound FA-512A (trade name of acrylate manufactured by Hitachi Chemical Co., Ltd., dicyclopentenyloxyethyl acrylate)
FA-711MM (trade name of acrylate manufactured by Hitachi Chemical Co., Ltd., pentamethylpiperidyl methacrylate)
R712 (trade name of acrylate manufactured by Nippon Kayaku Co., Ltd., ethoxylated bisphenol F diacrylate)

(2) Peroxide (radical initiator)
Perbutyl O (trade name of peroxide manufactured by Nippon Oil & Fats Co., Ltd. represented by the following structure, t-butylperoxy 2-ethylhexanoate, 10 hour half-life temperature; 73 ° C.),
Perhexyl O (trade name of peroxide manufactured by Nippon Oil & Fats Co., Ltd. shown by the following structure, t-hexylperoxy 2-ethylhexanoate, 10 hour half-life temperature; 70 ° C.),
Perhexa 25O (trade name of peroxide manufactured by NOF Corporation shown by the following structure, 2,5-dimethyl-2,5-bis (2-ethylhexanoylperoxy) hexane, 10-hour half-life temperature; 66 ° C),
Trigonox 22-70E (trade name of peroxide manufactured by Kayaku Akzo Co., Ltd. represented by the following structure, 1,1-di-t-butylperoxycyclohexane, 10 hour half-life temperature; 93 ° C.)

(3) Flexible material CTBNX-1300X31 (Ube Industries, Ltd. product name of carboxy terminal acrylonitrile butadiene copolymer, number average molecular weight: 10,000),
PB-3600 (trade name of epoxidized polybutadiene manufactured by Daicel Chemical Industries, Ltd., number average molecular weight: 3,500)

(4) Epoxy resin YDCN-700-7 (trade name of cresol novolac type epoxy resin manufactured by Toto Kasei Co., Ltd.)

(5) Epoxy resin curing agent Dicyandiamide (trade name: jER Cure DICY7, manufactured by Japan Epoxy Resin Co., Ltd.)

(6) Coupling agent γ-glycidoxypropyltrimethoxysilane (trade name: KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.),
γ-methacryloxypropyltrimethoxysilane (trade name: SZ-6030, manufactured by Toray Dow Corning Co., Ltd.)

(7) Filler a. Non-spherical filler R-972 (trade name of silica manufactured by Nippon Aerosil Co., Ltd., shape: agglomerated particles in which spherical primary fine particles are agglomerated, average particle size of secondary particles = about 16 μm), aspect Ratio = 1.5
HP-P1-HJ (trade name of boron nitride manufactured by Mizushima Alloy Iron Co., Ltd., shape: lump, average particle size = 0.8 μm), aspect ratio = 2
b. Spherical filler SO-E3 (trade name of silica manufactured by Admatex Co., Ltd., shape: spherical, average particle size = 1.0 μm, aspect ratio of about 1),
SO-E5 (trade name of silica manufactured by Admatechs Co., Ltd., shape: spherical, average particle size = 1.6 μm, aspect ratio of about 1),
SO-E6 (trade name of silica manufactured by Admatex Co., Ltd., shape: spherical, average particle size = 2.2 μm, aspect ratio of about 1),
SE5050-SEJ (trade name of silica manufactured by Admatechs Co., Ltd., shape: spherical, average particle size = 1.5 μm, aspect ratio of about 1, treated with surface treatment agent (epoxysilane),
SE5050-SMJ (trade name of silica manufactured by Admatechs Co., Ltd., shape: spherical, average particle size = 1.5 μm, aspect ratio of about 1, treated with a surface treatment agent (methacrylic silane),
SE2050-SMJ (trade name of silica manufactured by Admatechs Co., Ltd., shape: spherical, average particle size = 0.5 μm, aspect ratio of about 1, surface treatment agent (treated with methacrylic silane),

  Each material was mixed at the blending ratio shown in Table 1 and kneaded using a reiki machine, and then defoamed at 666.61 Pa (5 Torr) or less for 60 minutes to obtain a resin paste composition. . The characteristics (viscosity, bleedout length, die shear strength, chip warp, void) of this resin paste composition were examined by the following method. The results are shown in Table 1.

(1) Viscosity:
Using an EHD type rotational viscometer (manufactured by Tokyo Keiki Co., Ltd.) and a 3 ° cone rotor, the viscosity (Pa · s) at 25 ° C. of 0.5 rpm and 5 rpm was measured, and the ratio (thixotropy) was determined.

(2) Bleed-out length:
About 120 μg of resin paste composition is coated on a glass epoxy substrate with solder resist (AUS308) in a single spot (circular shape) and left at room temperature for 1 hour to cause bleeding out (spreading or spreading of resin paste composition). ) Was confirmed with a microscope (HI-SCOPE Advanced KH-3000 manufactured by Hilox Co., Ltd.). Thereafter, the sample was heated to 120 ° C. in 30 minutes and cured by heating at 120 ° C. for 1 hour, and the presence or absence of bleed-out after curing (spreading or spreading of the resin paste composition) was observed with a microscope ( HI-SCOPE Advanced KH-3000 manufactured by Hilox Co., Ltd., and the length of the bleed out based on the part where the bleed out length (the length of the resin paste composition spreads or oozes out) is the longest. Asked.

(3) Die share strength:
The resin paste composition was bonded by curing the following support member and Si chip under the following curing conditions. This was measured for shear adhesive strength (MPa) when heated (after being held at 260 ° C. for 20 seconds) using an automatic adhesive strength tester (BT4000, manufactured by Dage). The die shear strength was measured for 10 test pieces.
Chip size: 2mm x 2mm x 0.4mm
Support member: Glass epoxy substrate with solder resist (AUS308) Curing condition: Temperature rise to 120 ° C in 30 minutes, cure at 120 ° C for 1 hour

(4) Chip warpage:
The resin paste composition was bonded by curing the following support member and Si chip under the following curing conditions. The chip warpage was measured using a high-precision shape measurement system (KS-1100, manufactured by KEYENCE). In addition, the measurement of the chip warp was observed for five test pieces, and the warp for the diagonal was measured.
Chip size: 7mm x 7mm x 0.4mm
Support member: Glass epoxy substrate with solder resist (AUS308) Curing condition: Temperature rise to 120 ° C in 30 minutes, cure at 120 ° C for 1 hour

(5) Void:
Using the resin paste compositions obtained in Examples and Comparative Examples, the following support members and Si chips were cured and bonded under the following curing conditions. Thereafter, the number of voids was confirmed with a scanning ultrasonic microscope. Each of the five samples was observed, and the number of samples in which even one void was generated was determined.
Chip size: 7mm x 7mm x 0.4mm
Support member: Glass epoxy substrate with solder resist (AUS308) Curing condition: Temperature rise to 120 ° C in 30 minutes, cure at 120 ° C for 1 hour

  From the results of Table 1, the resin paste composition of the present invention (Example 1) has a die shear strength after curing even when cured at a low temperature as compared with a conventional paste composition that requires high temperature curing (Comparative Example 13). Strong and no bleed out is observed.

  In addition, since Comparative Example 11 is a spherical filler, the specific surface area per unit part by weight is small, so that the viscosity can be reduced. However, if the viscosity is too low, the workability is lowered (sagging), and the die share is reduced. There is a tendency for strength to decrease. The reason why the die shear strength is lowered is presumed that the spherical filler alone reduces the specific surface area and reduces the contact area with the substrate, and if the viscosity of the resin paste composition is too low, Dripping occurs, causing problems such as adhering to unnecessary portions and non-uniform coating amount, resulting in a decrease in workability.

  Further, in Comparative Example 12, the resin paste composition cannot be reduced in viscosity by not using a spherical filler, and workability is not good (an improvement in assembly speed). On the other hand, the present invention uses a spherical filler and a non-spherical filler in combination, and by using a filler containing them, excessive viscosity reduction is prevented, thereby improving workability (improving assembly speed). It turns out that the resin paste composition excellent in the adhesive strength which can maintain die shear strength is obtained.

  In short, in general, if the resin component to be used is reduced in viscosity, resin bleeding (bleed out) is more likely to occur, so in the resin paste composition of the present invention, as described above, due to the filler as a filler. It is characterized by designing a low viscosity, thereby preventing the occurrence of bleed out before curing.

On the other hand, bleed-out may occur if the standing time before curing becomes long. In addition, bleed out may occur during curing (temperature rise).
Bleed out is related to viscosity, and is particularly affected by the viscosity of the resin. As described above, when the resin component has a low viscosity, bleeding out is likely to occur. When the resin component has a high viscosity, the occurrence of bleeding out is suppressed, but the workability tends to decrease.

  Therefore, the present invention prevents the occurrence of bleed out by curing before the viscosity of the resin is lowered during curing, and a specific peroxide (radical initiator), a spherical filler, a non-spherical filler, It can be seen that the combination of these suppresses the occurrence of bleeding out before and during curing.

  That is, according to the resin paste composition of the present invention, low temperature curing and low viscosity are possible, and as a result, generation of bleed out can be prevented, and warpage of the semiconductor element and the substrate can be reduced. It can be seen that this can reduce the warpage.

DESCRIPTION OF SYMBOLS 1 Semiconductor element 2 BGA board 3 Solder ball 4 Die bonding material (resin paste composition)
5 Wire bond 6 Electrode on semiconductor element 7 Electrode on BGA substrate 8 Mold resin

Claims (8)

(A) a compound selected from an acrylic ester compound and a methacrylic ester compound,
(B) a peroxide represented by the following general formula (1) and represented by the general formulas (1) and (2) having a 10-hour half-life temperature of 60 to 80 ° C.,
(In the formula (1), R represents an alkyl group having 1 to 10 carbon atoms or an organic group represented by the following general formula (2), and R ¹ represents an alkyl group having 3 to 10 carbon atoms.)
(In Formula (2), R ² represents an alkylene group having 1 to 6 carbon atoms, and R ³ represents an alkyl group having 3 to 10 carbon atoms.)
(C) flexible material, and
(D) A resin paste composition comprising a filler containing a non-spherical filler and a spherical filler.   A semiconductor package is mounted on a BGA substrate and bonded, and then the wire on the electrode on the BGA substrate and the electrode on the semiconductor element existing around the semiconductor element is bonded by wire bonding between the BGA substrate and the semiconductor element. The resin paste composition according to claim 1, which is used for the adhesion.   The resin paste composition according to claim 1, wherein the non-spherical filler of the component (D) is a bulk filler.   Furthermore, the resin paste composition in any one of Claims 1-3 containing an epoxy resin and an epoxy resin hardening | curing agent.   Furthermore, the resin paste composition in any one of Claims 1-4 containing a coupling agent.   The resin paste composition according to claim 1, wherein the component (C) is a liquid rubber or a thermoplastic resin.   Content of the said (B) component is 0.5-10 mass parts with respect to 100 mass parts of said (A) component, The resin paste composition in any one of Claims 1-6.   A semiconductor device formed by bonding a semiconductor element to a BGA substrate using the resin paste composition according to claim 1, wire bonding, and sealing.