JP2009102602A - Adhesive composition and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive composition having a viscosity excellent in workability, and being superior in adhesiveness and thermal conductivity. <P>SOLUTION: This adhesive composition comprises a filler (A), a solvent (B) and a binder (C), wherein the filler (A) has a tap density of ≥6.5 g/m<SP>3</SP>and ≤8.5 g/m<SP>3</SP>, and is a mixed powder of a globular or substantially globular filler and a flat filler, and the solvent (B) has a boiling point of ≥150°C and ≤260°C, has a vapor rate of ≤10 (except 0) based on the vapor rate of 100 of n-butyl acetate at 25°C and 55% RH, and has ≥5% and ≤100% in a volume ratio based on the amount of the binder (C). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an adhesive composition and a semiconductor device.

  When manufacturing a semiconductor device, as a method of adhering a semiconductor element and a lead frame (supporting member for mounting a semiconductor element), a filler such as silver powder is dispersed in a resin such as an epoxy resin or a polyimide resin to form a paste. A method of using this as an adhesive is known. In this method, a paste-like adhesive is applied to a die pad of a lead frame using a dispenser, a printing machine, a stamping machine, etc., and then a semiconductor element is die-bonded and bonded by heat curing to manufacture a semiconductor device. The obtained semiconductor device is further sealed with a sealing material and packaged with a semiconductor, and then soldered and mounted on a wiring board. Since recent mounting requires high density and high efficiency, a surface mounting method in which a lead frame of a semiconductor device is directly soldered to the surface of a substrate is mainly used for solder mounting. In this surface mounting method, reflow soldering for heating the entire substrate with infrared rays or the like is used, and the package is heated to a high temperature of 200 ° C. or higher. At this time, if moisture exists in the inside of the package, particularly in the adhesive layer, the moisture is vaporized and wraps around between the die pad and the sealing material, and a crack (reflow crack) is generated in the package. This reflow crack significantly lowers the reliability of the semiconductor device, and is therefore a serious problem / technical problem. The adhesive often used for bonding the semiconductor element and the semiconductor element mounting support member has a high temperature. Reliability has been demanded starting with the adhesive strength of the time.

  Furthermore, in recent years, with the progress of high speed and high integration of semiconductor elements, high heat dissipation characteristics are required in order to ensure the operational stability of semiconductor devices in addition to the reliability such as adhesive strength that has been required conventionally. It came to be able to. That is, in order to solve the above-described problems, an adhesive composition having high adhesive force and high thermal conductivity, which is used as an adhesive for joining a heat dissipation member and a semiconductor element, has been demanded.

  There is a method to increase the filling rate of the filler in order to increase the thermal conductivity of the adhesive, but even when using a filler with a high tap density so far, if a single filler is used, the tap density will not increase sufficiently, Alternatively, there is a drawback that a highly filled conductive adhesive cannot be produced, for example, the filler settles and a uniform paste cannot be obtained. The method for producing a highly-fillable filler described in Non-Patent Document 1 is a method in which spherical particles are combined and mixed uniformly. That is, it is described that a relative density of 80% or more is theoretically obtained by regularly arranging spherical filler particles and filling the gaps with spherical filler particles having a smaller particle diameter.

In addition, as described in Patent Document 1, in order to prevent the viscosity of the adhesive from increasing and the workability from decreasing due to an increase in the filler content, if a large amount of solvent is mixed, adhesion after curing Solvents remained in the layer and voids were easily generated, leading to deterioration in heat dissipation characteristics and reliability.
JP 2006-73811 A Published by Nikkan Kogyo Shimbun, edited by the Society of Powder Engineering, Handbook of Powder Engineering, First Edition, 1st Edition, February 1986 (pages 101-107).

  The subject of this invention is providing the adhesive composition which has the viscosity excellent in workability | operativity, and was excellent in adhesiveness and heat conductivity. Moreover, the subject of this invention is providing the semiconductor device formed by adhere | attaching a semiconductor element and the supporting member for semiconductor element mounting using the said adhesive composition.

The present invention is (1) an adhesive composition containing a filler (A), a solvent (B) and a binder (C),
The filler (A) has a tap density of 6.5 g / cm ³ or more and 8.5 g / cm ³ or less, and is a mixed powder of a spherical or substantially spherical filler and a flat filler,
The solvent (B) has a boiling point of 150 ° C. or more and 260 ° C. or less, and an evaporation rate when the evaporation rate of n-butyl acetate at 25 ° C. and 55% RH is 100 or less (excluding 0). Further, the present invention relates to an adhesive composition characterized in that the blending amount with respect to the binder (C) is 5% or more and 100% or less by volume ratio.

  The present invention also relates to (2) the adhesive composition according to the above (1), wherein the viscosity at 25 ° C. at a rotational speed of 0.5 rpm is 70 Pa · s or more and 200 Pa · s or less.

  The present invention also relates to (3) a semiconductor device formed by bonding a semiconductor element and a semiconductor element mounting support member using the adhesive composition according to (1) or (2).

  ADVANTAGE OF THE INVENTION According to this invention, it has the viscosity excellent in workability | operativity and can provide the adhesive composition excellent in adhesiveness and heat conductivity. Moreover, according to this invention, the semiconductor device formed by adhere | attaching a semiconductor element and the supporting member for semiconductor element mounting using the said adhesive composition can be provided.

The adhesive composition of the present invention is an adhesive composition containing a filler (A), a solvent (B), and a binder (C), and the filler (A) has a tap density of 6.5 g / cm ³ or more. 8.5 g / cm ³ or less, and a mixed powder of a spherical or substantially spherical filler and a flat filler, and the solvent (B) has a boiling point of 150 ° C. or higher and 260 ° C. or lower and 25 ° C. And the evaporation rate when the evaporation rate of n-butyl acetate at 55% RH is 100 is 10 or less (excluding 0), and the blending amount with respect to the binder (C) is 5% or more and 100% or less by volume ratio. It is characterized by.

  Hereinafter, each component contained in the adhesive composition of the present invention will be described.

Filler (A)
The filler (A) used in the present invention has a tap density of 6.5 g / cm ³ or more and 8.5 g / cm ³ or less. When the tap density of the filler (A) is less than 6.5 g / cm ³ , the viscosity of the adhesive composition tends to increase and workability tends to decrease, and fillers exceeding 8.5 g / cm ³ Not realistic. The tap density of the filler (A) is preferably 7.0 g / cm ³ or more and 8.5 g / cm ³ or less, more preferably 7.0 g / cm ³ or more and 8.0 g / cm ³ or less.

  The filler (A) preferably has a relative density of 60% to 85%, more preferably 65% to 80%. If the relative density is less than 60%, the viscosity of the adhesive composition tends to increase and workability tends to decrease, and a filler exceeding 85% is not practical.

  The filler (A) used in the present invention is a mixed powder of a spherical or substantially spherical filler and a flat filler. In the present invention, by using a mixed powder of a spherical or substantially spherical filler and a flat filler, the tap density can be easily improved and adjusted, and both high thermal conductivity and low viscosity can be achieved. On the other hand, when a single-shaped filler is used, problems such as insufficient tap density and sedimentation of the filler are likely to occur.

The spherical or substantially spherical filler used in the present invention preferably has a long average particle size in the range of 0.6 μm to 3.0 μm, and more preferably in the range of 1 μm to 2.5 μm. If the average particle size of the major axis is less than 0.6 μm, the viscosity of the adhesive composition tends to increase and the workability tends to decrease, and if it exceeds 3.0 μm, the tap density of the mixed powder tends not to increase sufficiently. The spherical or substantially spherical filler preferably has a tap density of 4.2 g / cm ³ or more and 6.3 g / cm ³ or less, and 4.5 g / cm ³ or more and 6.0 g / cm ³ or less. Is more preferable. When the tap density is less than 4.2 g / cm ³ , the tap density of the mixed powder tends not to be sufficiently increased, and a spherical or substantially spherical filler exceeding 6.3 g / cm ³ is not practical. The spherical or substantially spherical filler preferably has a relative density in the range of 40% to 60%, and more preferably in the range of 43% to 57%. If the relative density is less than 40%, the tap density of the mixed powder tends not to increase sufficiently, and a spherical or nearly spherical filler exceeding 60% is not practical. The spherical or substantially spherical filler preferably has an aspect ratio in the range of 1 to 1.5. When the aspect ratio exceeds 1.5, the tap density of the mixed powder tends not to be sufficiently increased.

The flat filler used in the present invention preferably has a long average particle diameter in the range of 8 μm to 25 μm, and more preferably in the range of 10 μm to 20 μm. When the average particle diameter of the major axis is less than 8 μm, the tap density of the mixed powder tends not to be sufficiently increased, and when it exceeds 25 μm, workability such as dispensing property and printability tends to be lowered. Further, the flat filler preferably has a tap density of 4.8 g / cm ³ or more and 7.3 g / cm ³ or less, and preferably 5.0 g / cm ³ or more and 7.0 g / cm ³ or less. . If the tap density is less than 4.8 g / cm ³ , the tap density of the mixed powder tends not to be sufficiently increased, and a flat filler exceeding 7.3 g / cm ³ is not practical. Further, the flat filler preferably has a relative density of 45% or more and 70% or less, and more preferably 47% or more and 67% or less. If the relative density is less than 45%, the tap density of the mixed powder tends not to increase sufficiently, and a flat filler exceeding 70% is not practical. The flat filler preferably has an aspect ratio in the range of 3 or more and 20 or less, and more preferably in the range of 5 or more and 15 or less. If the aspect ratio is less than 3, the tap density of the mixed powder tends not to be sufficiently increased, and if it exceeds 20, the contact property between the fillers is deteriorated and sufficient thermal conductivity tends not to be obtained in the cured product.

  The average particle size is 50% by volume, and can be determined by measurement using a master sizer / laser scattering type particle size distribution analyzer (manufactured by Malvern).

  The tap density can be determined in accordance with JIS Z-2540 by putting 100 g of filler in a graduated cylinder, tapping 600 times, and converting from the input weight 100 g and the volume indicated by the graduated cylinder after 600 taps.

  The relative density can be obtained from the following equation.

Relative density (%) = (tap density / true density) × f × 100
(Where f is a correction coefficient based on actual measurement values)
The aspect ratio refers to the ratio of the major axis to the minor axis of the filler particles (major axis / minor axis). In the present invention, the filler particles are mixed well in a curable resin having a low viscosity, and the particles are allowed to settle, and the resin is cured as it is, and the resulting cured product is cut in the vertical direction, The shape of the appearing particles is magnified and observed with an electron microscope, and for each of at least 100 particles, the major axis / minor axis of each particle is determined, and the average value thereof is taken as the aspect ratio. Here, the minor axis is the distance between the two parallel lines that form the shortest interval among the combinations of two parallel lines that are in contact with the outside of the particles that appear on the cut surface. On the other hand, the major axis is a distance between two parallel lines that are perpendicular to the parallel line that determines the minor axis and that is the longest interval among the two parallel lines that are in contact with the outside of the particle. is there. The rectangle formed by these four lines is the size that the particles just fit within.

  The filler used in the present invention is a mixed powder of a spherical or substantially spherical filler and a flat filler, but the specifications and required characteristics of the adhesive composition such as viscosity, coating area, film thickness, and bonding member The combination and ratio of mixing may be appropriately selected according to the conditions. For example, the heat conduction in the planar direction preferably increases the mixing ratio of the flat filler from the viewpoint of the contact area between fillers, orientation, etc., and the heat conduction in the cross-sectional direction increases the volume occupied by a single particle in the cross-sectional direction. Therefore, it is preferable to increase the mixing ratio of the spherical or substantially spherical filler. Moreover, although adhesive strength changes with joining specifications, generally in the adhesive composition apply | coated smoothly with respect to the base material, a flat filler shows a higher value than a spherical or substantially spherical filler. From the viewpoints of heat conduction, adhesive strength, workability, reliability, etc., the mixing ratio of the spherical or substantially spherical filler and the flat filler is a weight ratio, and the spherical or substantially spherical filler: the flat filler is 10 : It is preferable that it is the range of 90-70: 30, and it is more preferable that it is the range of 20: 80-50: 50. When the mixing ratio of the flat filler is less than 30%, it is difficult to form a heat conduction path in the film thickness direction of the paste layer, and the effect of improving the heat conductivity tends to be inferior. The flat filler inside tends to settle.

  In addition, when a flat filler is mainly used, the viscosity of the adhesive composition increases. On the other hand, when the spherical or substantially spherical filler is mainly used, the viscosity becomes lower and the workability is improved than when the flat filler is mainly used. In addition, when the viscosity of the adhesive composition when the spherical or substantially spherical filler is mainly used and when the adhesive composition is mainly used when the flat filler is mainly used, the ratio of the spherical or substantially spherical filler is changed to that of the flat filler. Can be higher than the ratio.

  The filler used in the present invention preferably has a thermal conductivity of 50 W / mK to 2500 W / mK. When the thermal conductivity is less than 50 W / mK, there is a tendency that sufficient thermal conductivity cannot be obtained in the cured product, and those exceeding 2500 WmK are difficult to obtain and tend to be inferior in productivity.

  In the adhesive composition of the present invention, the blending ratio of the filler and the binder is preferably 93: 7 to 97: 3, more preferably 93: 7 to 95: 5, by weight. If the weight ratio of the filler is less than 93%, sufficient thermal conductivity tends to be not obtained in the cured product, and if it exceeds 97%, the adhesive strength tends to decrease. On the other hand, the blending ratio of the filler and the binder is a volume ratio, and the filler: binder is preferably 60:40 to 80:20, and more preferably 60:40 to 70:30. When the volume ratio of the filler is less than 60%, sufficient thermal conductivity tends to be not obtained in the cured product, and when it exceeds 80%, the adhesive strength tends to decrease.

  There is no restriction | limiting in particular as a filler used by this invention, Various well-known things can be used, for example, conductive powder, such as gold | metal | money, platinum, silver, copper, nickel, palladium, iron, aluminum, stainless steel Body, silicon oxide, aluminum nitride, boron nitride, aluminum borate, aluminum oxide, magnesium oxide, diamond, and other nonconductive powders. Among these, diamond, boron nitride, aluminum nitride, alumina, gold Platinum, silver, copper, nickel, aluminum, and palladium are preferable in terms of ensuring high thermal conductivity and availability, and silver is particularly preferable in terms of oxidation resistance, cost, and characteristics. These can be used alone or in combination of two or more.

In the present invention, since a mixed powder having a tap density of 6.5 g / cm ³ or more and 8.5 g / cm ³ or less is used, when mixing with a binder, it is not necessary to premix filler particles with each other. Since it is only necessary to mix the mixed powder, the time required for mixing and dispersing can be shortened. And since the mixed powder with high relative density of 60% or more and 85% or less is used, it can be made into a paste with a small amount of binder, and when mixed with the binder, the viscosity immediately after starting mixing is also low, so it is easy Can be mixed uniformly.

Solvent (B)
The adhesive composition containing the solvent contains a solvent in the volume reduction amount of the adhesive composition after being applied and after being cured by heat treatment, than the adhesive composition not containing the solvent. Only big. Further, the adhesive composition containing a solvent in the course of heat treatment has a much lower viscosity of the adhesive composition, and the filler contained in the adhesive composition becomes dense in the binder. Due to these factors, it is considered that the adhesive composition containing the solvent has better thermal conductivity and less variation than the adhesive composition containing no solvent. Further, the solvent is preferably a solvent in which the viscosity of the adhesive composition at the time of heat treatment is greatly reduced. Conversely, when the heat treatment is performed with fast drying properties, the solvent is dried and the viscosity of the adhesive composition is not greatly reduced. It is not preferable.

  When various solvents were examined based on the above idea, the boiling point was 150 ° C. or more and 260 ° C. or less, and the evaporation rate when the evaporation rate of n-butyl acetate at 25 ° C. and 55% RH was 100 was 10 or less. It was found that the solvent (except 0) exhibited the effects of the present invention.

  The solvent (B) used in the present invention has a boiling point of 150 ° C. or higher and 260 ° C. or lower. When the boiling point of the solvent (B) is less than 150 ° C., the solvent contained in the adhesive composition after coating is quickly dried, that is, the solvent composition is rapidly dried during the coating to heat treatment process, so that the viscosity of the adhesive composition is high. Therefore, the filler does not become dense in the binder, the heat conduction after the heat treatment decreases, and the variation increases. If the boiling point of the solvent (B) exceeds 260 ° C., the drying speed of the solvent is slow, so that it is unsuitable for a short heat treatment step. The boiling point of the solvent (B) is preferably 170 ° C. or higher and 240 ° C. or lower, more preferably 180 ° C. or higher and 220 ° C. or lower.

  The solvent (B) used in the present invention has an evaporation rate of 10 or less (excluding 0) when the evaporation rate of n-butyl acetate at 25 ° C. and 55% RH is 100. When a solvent having an evaporation rate exceeding 10 is used, the viscosity of the adhesive composition is greatly reduced because the solvent contained in the adhesive composition after coating is quickly dried, that is, the solvent is quickly dried during the coating to heat treatment steps. do not do. Therefore, the filler does not become dense in the binder, the heat conduction after the heat treatment decreases, and the variation increases. The evaporation rate of the solvent (B) is preferably 5 or less (excluding 0), more preferably 3 or less (excluding 0).

In the present invention, the evaporation rate is a relative rate when the evaporation rate of n-butyl acetate at a temperature of 25 ° C. and a relative humidity of 55% RH is 100. Specifically, 10 g of a solvent is dropped onto a glass petri dish having a diameter of 90 mm, and the dry weight loss after leaving this in an atmosphere of 25 ° C., 55% RH and 1 atm for 1 hour is defined as A. Also, B represents the amount of decrease in dry weight after 10 g of n-butyl acetate is left in the same atmosphere as above for 1 hour. The evaporation rate can be determined by A / B × 100.
Specific examples of the solvent (B) used in the present invention include ethylene glycol butyl ether, ethylene glycol phenyl ether, diethylene glycol methyl ether, diethylene glycol ethyl ether, diethylene glycol butyl ether, diethylene glycol isobutyl ether, diethylene glycol hexyl ether, triethylene glycol methyl ether, Diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl methyl ether, triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, ethylene glycol ethyl ether acetate Ethylene glycol butyl ether acetate, diethylene glycol ethyl ether acetate, diethylene glycol butyl ether acetate, propylene glycol propyl ether, dipropylene glycol methyl ether, dipropylene glycol ethyl ether, dipropylene glycol propyl ether, dipropylene glycol butyl ether, dipropylene glycol dimethyl ether, tri Propylene glycol methyl ether, tripropylene glycol dimethyl ether, dipropylene glycol methyl ether acetate, 3-methyl-3-methoxybutanol, ethyl lactate, butyl lactate, γ-butyrolactone, α-terpineol, isophorone, p-cymene, 1,3- Dimethyl-2-imidazolidinone, Nisoru and the like.

The said solvent can be used individually by 1 type or in mixture of 2 or more types. When mixing two or more solvents, the boiling point of the mixed solvent is 150 ° C. or higher and 260 ° C. or lower, and the evaporation rate of n-butyl acetate at 25 ° C. and 55% RH is 100. The evaporation rate is selected to be 10 or less (excluding 0).
The blending amount of the solvent is 10% or more and 100% or less, and preferably 40% or more and 100% or less with respect to the binder (C) from the viewpoint of thermal conductivity and workability. Moreover, it is preferable that the compounding quantity of a solvent is the range of 2-10 weight% with respect to adhesive composition, and it is more preferable that it is the range of 2-7.5 weight%.

Binder (C)
The binder (C) used in the present invention is an epoxy resin (C1), an acrylonitrile butadiene copolymer (C2), an epoxidized polybutadiene (C3), an epoxy resin curing agent (C4), an acrylate compound or a methacrylate compound. (C5) and a radical initiator (C6) are contained.

  Hereinafter, the components (C1) to (C6) included in the binder (C) will be described.

Epoxy resin (C1)
The epoxy resin (C1) used in the present invention 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 Corporation, Product name), R-301 (Oilized Shell Epoxy Co., Ltd., product name), YL-980 (Oilized Shell Epoxy Co., Ltd. product name)], Bisphenol F type epoxy resin [YDF-170 (Tohto Kasei Co., Ltd., Product) Name)], bisphenol AD type epoxy resin [R-1710 (Mitsui Petrochemical Co., Ltd., trade name)], phenol novolac type epoxy resin [N-730S (Dainippon Ink Chemical Co., Ltd., trade name), Quatrex- 2010 (Dow Chemical Company, trade name)], cresol novolac type epoxy resin [YDCN-70 S (Toto Kasei Co., Ltd., trade name), EOCN-100 (Nippon Kayaku Co., Ltd., trade name)], polyfunctional epoxy resin [EPPN-501 (Nippon Kayaku Co., Ltd., trade name), TACTIX-742 (Dow)・ Chemical company, trade name), VG-3010 (Mitsui Petrochemical Co., Ltd., trade name), 1032S (Oka Chemical Shell Epoxy Co., Ltd., trade name)], epoxy resin having a naphthalene skeleton [HP-4032 (Dainippon) Ink Chemical Industry Co., Ltd., trade name)], cycloaliphatic epoxy resin [EHPE-3150, CEL-3000 (Daicel Chemical Industries, trade name), DME-100 (New Nippon Rika Co., Ltd., trade name)], Aliphatic epoxy resin [W-100 (Shin Nihon Rika Co., Ltd., trade name)], amine type epoxy resin [ELM-100 (Sumitomo Chemical Co., Ltd., merchandise) ), YH-434L (Toto Kasei Co., Ltd., trade name), TETRAD-X, TETRAC-C (Mitsubishi Gas Chemical Co., Ltd., trade name)], resorcinol type epoxy resin [Denacol EX-201 (Nagase Chemical Industries, Ltd., Product name)], neopentyl glycol type epoxy resin [Denacol EX-211 (Nagase Kasei Kogyo Co., Ltd., trade name)], hexane dinel 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., trade name)], represented by the following general formula (I) Epoxy resin [E-XL-24, E-XL-3L (Mitsui Toatsu Chemicals, Inc. , Product name)] and the like.

(In general formula (I), a represents an integer of 0 to 5)
These epoxy resins may be used alone or in combination of two or more.

  Moreover, as an epoxy resin (C1), you may include the epoxy compound (reactive diluent) which has only one epoxy group in 1 molecule. Such an epoxy compound is used in a range that does not impair the properties of the adhesive composition of the present invention, but is preferably used in a range of 0 to 30% by weight with respect to the total amount of the epoxy resin. Examples of such commercially available epoxy compounds include PGE (Nippon Kayaku Co., Ltd., trade name), PP-101 (Toto Kasei Co., Ltd., trade name), ED-502, 509, 509S (Asahi Denka Kogyo Co., Ltd., Product name), YED-122 (Oilized Shell Epoxy Co., Ltd., trade name), KBM-403 (Shin-Etsu Chemical Co., Ltd., trade name), TSL-8350, TSL-8355, TSL-9905 (Toshiba Silicone Co., Ltd.) Product name).

Acrylonitrile butadiene copolymer (C2)
The acrylonitrile butadiene copolymer (C2) used in the present invention preferably has at least one functional group selected from an epoxy group, a carboxyl group, an amino group and a vinyl group in the molecule. The acrylonitrile butadiene copolymer (C2) is a ratio of the epoxy resin (C1) and the epoxy resin: acrylonitrile butadiene copolymer = 10: 90 to 90:10 (parts by weight) in advance at 20 ° C. to 120 ° C. The reaction can be carried out for about minutes to 6 hours. In the reaction, an organic solvent having a relatively high boiling point such as butyl cellosolve, carbitol, butyl cellosolve, carbitol acetate, ethylene glycol diethyl ether, α-terpineol can be used as necessary.

  The number average molecular weight of the acrylonitrile butadiene copolymer (C2) is preferably 500 to 10,000. When the number average molecular weight is less than 500, chip warpage tends to occur, and when it exceeds 10,000, the viscosity of the adhesive composition tends to increase and workability tends to be inferior. The number average molecular weight is a value measured by a vapor pressure osmosis method or a value measured by gel permeation chromatography using a standard polystyrene calibration curve (hereinafter referred to as GPC method).

  The blending amount of the acrylonitrile butadiene copolymer (C2) is preferably 10 to 100 parts by weight, and more preferably 30 to 80 parts by weight with respect to 100 parts by weight of the epoxy resin (C1). When the blending amount is less than 10 parts by weight, chip warpage tends to occur easily, and when it exceeds 100 parts by weight, the viscosity increases and workability tends to decrease.

Epoxidized polybutadiene (C3)
The epoxidized polybutadiene (C3) used in the present invention is preferably one having an epoxy equivalent of 100 to 500 (g / eq). When the epoxy equivalent is less than 100 (g / eq), the viscosity increases and the workability of the adhesive composition tends to decrease. When it exceeds 500 (g / eq), the adhesive strength during heating tends to decrease. is there. The epoxy equivalent is determined by the perchloric acid method. Epoxy polybutadiene (C3) having a hydroxyl group in the molecule may be used.

  The number average molecular weight of the epoxidized polybutadiene (C3) is preferably 500 to 10,000. When the number average molecular weight is less than 500, chip warpage tends to occur, and when it exceeds 10,000, the viscosity of the adhesive composition tends to increase and workability tends to be inferior. The number average molecular weight is a value measured by GPC method.

  The blending amount of the epoxidized polybutadiene (C3) is preferably 10 to 100 parts by weight, and more preferably 30 to 80 parts by weight with respect to 100 parts by weight of the epoxy resin (C1). If the blending amount is less than 10 parts by weight, chip warpage tends to occur easily, and if it exceeds 100 parts by weight, the viscosity of the adhesive composition tends to increase and the workability tends to be inferior.

Epoxy resin curing agent (C4)
The epoxy resin curing agent (C4) used in the present invention is not particularly limited as long as it is usually used as a curing agent for epoxy resins. For example, phenol novolak resin [H-1 (Maywa Kasei Co., Ltd., trade name), VR-9300 (Mitsui Toatsu Chemical Co., Ltd., trade name)], phenol aralkyl resin [XL-225 (Mitsui Toatsu Chemical Co., Ltd., trade name)], allylated phenol novolak resin [AL-VR-9300 (Mitsui East) Pressure Chemical Co., Ltd., trade name)], microcapsule type curing agent consisting of a reaction product of epoxy resin and amine compound [Novacure (Asahi Kasei Kogyo Co., Ltd., trade name)], bisphenol F, bisphenol A, bisphenol AD, allylated bisphenol F, allylated bisphenol A, allylated bisphenol AD, dicyandiamide, bottom Special phenol resin represented by general formula (II) [PP-700-300 (Nippon Petrochemical Co., Ltd., trade name)], dibasic acid dihydrazide represented by general formula (III) below [ADH, PDH, SDH] (Nippon Hydrazine Kogyo Co., Ltd., trade name)] and the like.

(In general formula (II), R ¹ represents an alkyl group having 1 to 6 carbon atoms, R ² represents hydrogen or an alkyl group having 1 to 6 carbon atoms, and b represents an integer of 2 to 4).

(In the general formula (III), R ³ represents a divalent aromatic hydrocarbon 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.)
These epoxy resin curing agents (C4) may be used alone or in combination of two or more.

  It is preferable that the compounding quantity of an epoxy resin hardening | curing agent (C4) is 0.01-90 weight part with respect to 100 weight part of epoxy resins (C1), and it is more preferable that it is 0.1-50 weight part. . When the compounding amount of the epoxy resin curing agent (C4) is less than 0.01 parts by weight, the curability tends to decrease, and when it exceeds 90 parts by weight, the viscosity increases and the workability tends to decrease.

  If necessary, a curing accelerator can be added to the adhesive composition of the present invention. Examples of the curing accelerator include organic boron salt compounds [EMZ · K, TPPK (Hokuko Chemical Co., Ltd., trade name)], tertiary amines or salts thereof [DBU, U-CAT102, 106, 830, 840, 5002 ( San Apro, trade name)], imidazoles [Cureazole, 2P4MHZ, C17Z, 2PZ-OK (Shikoku Chemicals, trade name)] and the like.

  The epoxy resin curing agent (C4) and the curing accelerator added as necessary may be used alone, or a plurality of epoxy resin curing agents (C4) and a curing accelerator may be used in appropriate combination. Also good. It is preferable that the compounding quantity of a hardening accelerator is 20 weight part or less with respect to 100 weight part of epoxy resins (C1).

Acrylic ester compound or methacrylic ester compound (C5)
The acrylic ester compound or methacrylic ester compound (C5) used in the present invention is a compound having one or more acrylic groups or methacrylic groups in one molecule, preferably the following general formulas (IV) to (IV): The compound represented by XIII) is used.

The compound represented by general formula (IV) is the following compound.

(In General Formula (IV), R ⁴ represents hydrogen or a methyl group, and R ⁵ is an aliphatic hydrocarbon group having a divalent aliphatic or cyclic structure having 1 to 100 carbon atoms, preferably 1 to 36 carbon atoms. Represents.)
Specific examples of the compound represented by the general formula (IV) 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] acrylate compounds such as decyl 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, isobornyl methacrylate, tricyclo [5.2.1.0 ^{2, 6]} methacrylate and decyl methacrylate And the like; compounds.

The compound represented by general formula (V) is the following compound.

(In general formula (V), R ⁴ and R ⁵ represent the same as those in general formula (IV).)
Specific examples of the compound represented by the general formula (V) include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and the like.

The compound represented by general formula (VI) is the following compound.

(In general formula (VI), R ⁴ represents the same as in general formula (IV), R ⁶ represents hydrogen, methyl group or phenoxymethyl group, R ⁷ represents hydrogen, alkyl having 1 to 6 carbon atoms. A group, a dicyclopentenyl group, a phenyl group or a benzoyl group, and b represents an integer of 1 to 50.)
Specific examples of the compound represented by the general formula (VI) include diethylene glycol acrylate, polyethylene glycol acrylate, polypropylene glycol acrylate, 2-methoxyethyl acrylate, 2-ethoxyethyl acrylate, 2-butoxyethyl acrylate, methoxydiethylene glycol acrylate, and methoxypolyethylene. Acrylate compounds such as glycol acrylate, dicyclopentenyloxyethyl acrylate, 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 methacrylate, 2-methoxyethyl methacrylate, 2-ethoxyethyl methacrylate, 2-butoxyethyl methacrylate, methoxydiethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, dicyclopentenyloxyethyl methacrylate, 2-phenoxyethyl methacrylate, phenoxydiethylene glycol methacrylate , Methacrylate compounds such as phenoxypolyethylene glycol methacrylate, 2-benzoyloxyethyl methacrylate, 2-hydroxy-3-phenoxypropyl methacrylate;

The compound represented by the general formula (VII) is the following compound.

(In General Formula (VII), R ⁴ represents the same as in General Formula (IV), R ⁸ represents a phenyl group, a nitrile group, —Si (OR ⁹ ) ₃ (R ⁹ has 1 to 6 carbon atoms). Represents an alkyl group),

(R ¹⁰ , R ¹¹ and R ¹² each independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms, and R ¹³ represents hydrogen, an alkyl group having 1 to 6 carbon atoms or a phenyl group). c represents a number of 0, 1, 2 or 3. )
Specific examples of the compound represented by the general formula (VII) include benzyl acrylate, 2-cyanoethyl acrylate, γ-acryloyloxypropyltrimethoxysilane, glycidyl acrylate, tetrahydrofurfuryl acrylate, tetrahydropyranyl acrylate, dimethylaminoethyl acrylate, Diethylaminoethyl acrylate, 1,2,2,6,6, -pentamethylpiperidinyl acrylate, 2,2,6,6, -tetramethylpiperidinyl acrylate, acryloyloxyethyl phosphate, acryloyloxyethyl phenyl acid phosphate, acrylate compounds such as β-acryloyloxyethyl hydrogen phthalate and β-acryloyloxyethyl hydrogen succinate; 2-cyanoethyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, glycidyl methacrylate, tetrahydrofurfuryl methacrylate, tetrahydropyranyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, 1,2,2,6,6-penta Methacrylate such as methyl piperidinyl methacrylate, 2,2,6,6, -tetramethylpiperidinyl methacrylate, methacryloyloxyethyl phosphate, methacryloyloxyethyl phenyl acid phosphate, β-methacryloyloxyethyl hydrogen phthalate, β-methacryloyloxy Methacrylate compounds such as ethyl hydrogen succinate;

The compound represented by the general formula (VIII) is the following compound.

(In general formula (VIII), R ⁴ and R ⁵ are the same as those in general formula (IV).)
Specific examples of the compound represented by the general formula (VIII) include ethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,3. -Diacrylate compounds such as butanediol diacrylate, neopentyl glycol diacrylate, dimer diol diacrylate; ethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonane Dimethacrylate compounds such as diol dimethacrylate, 1,3-butanediol dimethacrylate, neopentyl glycol dimethacrylate, and dimer diol dimethacrylate;

The compound represented by the general formula (IX) is the following compound.

(In general formula (IX), R ⁴ represents the same as in general formula (IV), and R ⁵ and b represent the same as in general formula (VI).)
Specific examples of the compound represented by the general formula (IX) include diacrylates such as diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, and polypropylene glycol diacrylate. Compounds; dimethacrylate compounds such as diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, tripropylene glycol dimethacrylate, polypropylene glycol dimethacrylate; and the like.

The compound represented by general formula (X) is the following compound.

(In general formula (X), R ⁴ represents the same as in general formula (IV), and R ¹⁴ and R ¹⁵ each independently represent hydrogen or a methyl group.)
Specific examples of the compound represented by the general formula (X) include a reaction product of 1 mol of bisphenol A, bisphenol F or bisphenol AD and 2 mol of glycidyl acrylate, 1 mol of bisphenol A, bisphenol F or 1 mol of bisphenol AD and 2 mol of glycidyl methacrylate. There are reactants.

The compound represented by the general formula (XI) is the following compound.

(In general formula (XI), R ⁴ represents the same as in general formula (IV), R ¹⁴ and R ¹⁵ represent the same as in general formula (X), and R ¹⁶ and R ¹⁷ represent Independently represents hydrogen or a methyl group, and d and e each independently represent an integer of 1 to 20.)
Specific examples of the compound represented by the general formula (XI) 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, dimethacrylate of polyethylene oxide adduct of bisphenol F or bisphenol AD, dimethacrylate of polypropylene oxide adduct of bisphenol A, bisphenol F or bisphenol AD.

The compound represented by the general formula (XII) is the following compound.

(In general formula (XII), R ⁴ represents the same as in general formula (IV), R ¹⁸ , R ¹⁹ , R ²⁰ and R ²¹ each independently represent hydrogen or a methyl group, Represents an integer of 20.)
Specific examples of the compound represented by the general formula (XII) include bis (acryloyloxypropyl) polydimethylsiloxane, bis (acryloyloxypropyl) methylsiloxane-dimethylsiloxane copolymer, bis (methacryloyloxypropyl) polydimethylsiloxane, bis ( Methacryloyloxypropyl) methylsiloxane-dimethylsiloxane copolymer.

The compound represented by the general formula (XIII) is the following compound.

(In general formula (XIII), R ⁴ represents the same as in general formula (IV), and g, h, i, j and k each independently represent a number of 1 or more, preferably 1 to 10. )
Specific examples of the compound represented by the general formula (XIII) include a reaction product obtained by reacting a polybutadiene to which maleic anhydride is added and an acrylic ester compound or a methacrylic ester compound having a hydroxyl group in the molecule, and hydrogen thereof. There is no particular limitation as long as it is a compound having an additive and having at least one acrylic group or methacryl group in one molecule. For example, MM-1000-80, MAC-1000-80 (both Nippon Petrochemical Co., Ltd.) Product name).

  As the acrylic ester compound or methacrylic ester compound (C5), the above compounds can be used alone or in combination of two or more.

  The blending amount of the acrylic ester compound or the methacrylic ester compound (C5) is 5 to 100 with respect to 100 parts by weight of the total amount of the epoxy resin (C1), the acrylonitrile butadiene copolymer (C2) and the epoxidized polybutadiene (C3). It is preferable that it is a weight part, and it is more preferable that it is 10-50 weight part. If the blending amount is less than 5 parts by weight, the curability in a short time tends to be inferior, and if it exceeds 100 parts by weight, the adhesive strength tends to decrease.

Radical initiator (C6)
The radical initiator (C6) used in the present invention is not particularly limited, but is preferably a peroxide from the viewpoint of voids and the like, and is decomposed from the viewpoint of curability and viscosity stability of the adhesive composition. The thing whose temperature is 70-170 degreeC is preferable.

  Specific examples of the radical initiator (C6) include 1,1,3,3-tetramethylperoxy 2-ethylhexanoate, 1,1-bis (t-butylperoxy) cyclohexane, 1,1-bis. (T-butylperoxy) cyclododecane, di-t-butylperoxyisophthalate, t-butylperbenzoate, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di ( t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne, cumene hydroperoxide and the like.

  It is preferable that the compounding quantity of a radical initiator (C6) is 0.1-10 weight part with respect to 100 weight part of total amounts of an acrylic ester compound or a methacrylic ester compound (C5), 0.5-5 More preferred are parts by weight.

Other additives The adhesive composition of the present invention may further include a moisture absorbent such as calcium oxide and magnesium oxide, a silane coupling agent, a titanate coupling agent, an aluminum coupling agent, and a zircoaluminate coupling as necessary. Adhesive strength improvers such as additives, nonionic surfactants, wetting improvers such as fluorosurfactants, antifoaming agents such as silicone oil, ion trapping agents such as inorganic ion exchangers, polymerization inhibitors, bleed inhibitors Other additives such as can be appropriately added.

  Examples of the silane coupling agent include vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxy. Silane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, hexamethyldisilazane, N, O- (bistrimethylsilyl) acetamide, N-methyl-3-aminopropyltrimethoxysilane, 4,5-dihydroimidazolepropyltriethoxysilane, γ-mercaptopropyltriethoxysilane, γ-mercaptopropylme Rudimethoxysilane, 3-cyanopropyltrimethoxysilane, methyltri (methacryloyloxyethoxy) silane, methyltri (glycidyloxy) silane, 2-ethylhexyl-2-ethylhexylphosphonate, γ-glycidoxypropylmethyldimethoxysilane, vinyltriacetoxysilane Γ-anilinopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, N-trimethylsilylacetamide, dimethyltrimethylsilylamine, diethyltrimethylsilylamine, trimethylsilylimidazole, trimethylsilyl isocyanate, dimethylsilyl diisocyanate, Methyl silyl triisocyanate, vinyl silyl triisocyanate, fluoro Examples include phenylsilyl triisocyanate, tetraisocyanate silane, and ethoxysilane triisocyanate.

  Examples of titanate coupling agents include isopropyl triisostearoyl titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri (dioctyl phosphate) titanate, Isopropyltricumylphenyl titanate, isopropyltris (dioctylpyrophosphate) titanate, tetraisopropylbis (dioctylphosphite) titanate, tetraoctylbis (ditridecylphosphite) titanate, tetra (2,2-diallyloxymethyl-1-butyl) Bis (ditridecyl) phosphite titanate, dicumylpheny Oxyacetate titanate, bis (dioctylpyrophosphate) oxyacetate titanate, diisostearoyl ethylene titanate, bis (dioctylpyrophosphate) ethylene titanate, diisopropoxybis (2,4-pentadionate) titanium (IV), diisopropylbistriethanol Amino titanate, titanium lactate, acetoacetic ester titanate, di-i-propoxybis (acetylacetonato) titanium, di-n-butoxybis (triethanolaminato) titanium, dihydroxybis (lactato) titanium, titanium-i-propoxy Octylene glycolate, titanium stearate, tri-n-butoxy titanium monostearate, titanium lactate ethyl ester, titanium tri There is ethanol Ami sulfonate, and the like.

  Examples of the polymerization inhibitor include quinones, hydroquinone, nitro / nitroso compounds, amines, polyoxy compounds, p-tert-butylcatechol, picric acid, dithiobenzoyl disulfide and other sulfur-containing compounds, cupric chloride, diphenylpicryl. Examples include, but are not limited to, hydrazyl, tri-p-nitrophenylmethyl, triphenylferdazyl, N- (3-N-oxyanilino-1,3-dimethylbutylidene) aniline oxide, and the like. .

  Examples of the bleed inhibitor include fatty acids such as perfluorooctanoic acid, octanoic acid amide, and oleic acid, perfluorooctylethyl acrylate, silicone, and the like.

  The adhesive composition of the present invention preferably has a viscosity at a rotation speed of 0.5 rpm at 25 ° C. of 70 Pa · s to 200 Pa · s, more preferably 90 Pa · s to 150 Pa · s. When the viscosity is less than 70 Pa · s, the adhesive composition after application tends to spread, and when it exceeds 200 Pa · s, the workability tends to deteriorate.

  The adhesive composition of the present invention preferably has a thixo value of 4.0 or more and 9.5 or less, and more preferably 5.0 or more and 9.5 or less. When the thixo value is less than 5.0, the adhesive composition after application tends to bleed, and when it exceeds 9.5, bleed does not occur but the workability tends to be deteriorated. There is a tendency that the smoothness of the surface of the adhesive composition is deteriorated.

The viscosity of the adhesive composition is determined from the formula (1) using an EHD type rotational viscometer manufactured by Tokyo Keiki Seisakusho, measuring at a rotation speed of 0.5 rpm at 25 ° C., and using a value at 0.5 rpm. I can do it.
Viscosity (Pa · s) = value at 0.5 rpm × f1 (1)
(In Formula (1), f1 is a correction coefficient of 0.5 rpm.)
The thixo value is measured by using an EHD type rotational viscometer manufactured by Tokyo Keiki Seisakusho at a rotation speed of 0.5 rpm and 5 rpm at 25 ° C., and using formula (2) using a value at 0.5 rpm and 5 rpm. You can ask.
Thixo value = (value at 0.5 rpm × f1) / (value at 5 rpm × f2) (2)
(In Formula (2), f1 is a correction coefficient of 0.5 rpm, and f2 is a correction coefficient of 5 rpm.)
In order to produce the adhesive composition of the present invention, the filler (A), the solvent (B), and the binder (C) are stirred together in a batch or divided together with a diluent and various additives that are added as necessary. A dispersing / dissolving device such as a vessel, a raker, a three-roller, a planetary mixer, etc. may be appropriately combined, and heated, mixed, dissolved, granulated and kneaded or dispersed as necessary to form a uniform paste.

  The glass transition point of the hardened | cured material obtained by heat-curing the adhesive composition of this invention is 40-180 degreeC normally, Preferably it is the range of 70-180 degreeC. When the glass transition point is less than 40 ° C., it may be very difficult or impossible to produce an adhesive composition having a good balance with other properties such as thermal conductivity, adhesive strength, and flexibility of the joint. is there. When the glass transition point exceeds 180 ° C., the ratio of the epoxy resin has to be reduced, which may reduce the adhesive strength.

  The semiconductor device of the present invention can be obtained by bonding a semiconductor element and a support member for mounting a semiconductor element using the adhesive composition of the present invention. As shown in FIGS. 1 and 2, after bonding the semiconductor element to the semiconductor element mounting support member, a wire bonding process and a sealing process are performed as necessary. Examples of the semiconductor element include an IC chip and an LED chip. As the support member for mounting a semiconductor element, for example, a lead frame such as a 42 alloy lead frame, a copper lead frame, a palladium PPF lead frame, a glass epoxy substrate (a substrate made of glass fiber reinforced epoxy resin), a BT substrate (cyanate monomer and its component) And an organic substrate such as a BT resin-containing substrate made of an oligomer and bismaleimide.

  In order to adhere a semiconductor element to a semiconductor element mounting support member using the adhesive composition of the present invention, first, the adhesive composition is applied to the semiconductor element mounting support member by a dispensing method, a screen printing method, a stamping method, or the like. After coating, the semiconductor element can be pressure-bonded and then heated and cured using a heating device such as an oven or a heat block. Heat curing is usually performed by heating at 50 to 300 ° C. for 1 second to 10 hours. Furthermore, it can be set as the completed semiconductor device by sealing by a normal method after passing through a wire bond process.

  EXAMPLES Next, although an Example demonstrates this invention in detail, this invention is not restrict | limited by this. The materials used in Examples 1 to 6 and Comparative Examples 1 to 6 were prepared or obtained as follows.

Filler (A):
AgC-224 (Fukuda Metal Foil Powder Co., Ltd., trade name, flat silver powder, average particle size 10 μm, tap density 5.5 g / cm ³ , relative density 52%)
SPQ05S (Mitsui Mining & Smelting Co., Ltd., trade name, spherical silver powder, average particle size 0.85 μm, tap density 4.6 g / cm ³ , relative density 44%)
SPQ08S (Mitsui Mining & Smelting Co., Ltd., trade name, spherical silver powder, average particle size 1.5 μm, tap density 4.8 g / cm ³ , relative density 46%)
TCG-1 (Tokuriki Chemical Laboratory Co., Ltd., trade name, flat silver powder, average particle size 4.5 μm, tap density 5.0 g / cm ³ , relative density 48%)
Solvent (B):
Dipropylene glycol methyl ether (boiling point 188 ° C, evaporation rate 3)
Diethylene glycol dibutyl ether (boiling point 256 ° C, evaporation rate <1)
Propylene glycol methyl ether acetate (boiling point 156 ° C, evaporation rate 34)
Diethylene glycol 2-ethylhexyl ether (boiling point 272 ° C., evaporation rate <1)
Binder (C):
Epoxy resin (C1): YDF-170 (Toto Kasei Co., Ltd., trade name, bisphenol F type epoxy resin, epoxy equivalent = 170) 7.5 parts by weight and YL-980 (Oilized Shell Epoxy Co., Ltd., trade name, bisphenol) 7.5 parts by weight of A-type epoxy resin, epoxy equivalent = 185) were heated to 80 ° C. and stirred for 1 hour to obtain a uniform epoxy resin solution.

Acrylonitrile butadiene copolymer (C2): CTBNX-1300 × 9 (Ube Industries, Ltd., trade name, carboxyl group-terminated acrylonitrile butadiene copolymer)
Epoxidized polybutadiene (C3): E-1000-8.0 (Nippon Petrochemical Co., Ltd., trade name)
Epoxy resin curing agent (C4): Dicyandiamide Curing accelerator: C17Z (Shikoku Chemicals, trade name, imidazole)
Methacrylic acid ester compound (C5): ethylene glycol dimethacrylate radical initiator (C6): dicumyl peroxide Diluent: PP-101 (Toto Kasei Co., Ltd., trade name, alkylphenylglycidyl ether)

Examples 1-6
Each material was mixed at a blending ratio (% by weight) shown in Table 1 and kneaded using three rolls, and then defoamed for 10 minutes at 5 Torr or less to obtain an adhesive composition.

Comparative Examples 1-6
Each material was mixed at a blending ratio (% by weight) shown in Table 2 and kneaded using three rolls, and then defoamed at 5 Torr or less for 10 minutes to obtain an adhesive composition.

  The properties of the filler and the solvent, and the properties of the adhesive compositions obtained in Examples 1 to 6 and Comparative Examples 1 to 6 were examined by the following methods. The results are shown in Tables 1 and 2.

(1) Average particle diameter: After taking a small amount of filler in a test tube and dispersing with water or isopropyl alcohol, the particle diameter is measured by a laser diffraction / scattering method (Mastersizer 2000, Malvern), and 50% by volume. The particle size was defined as the average particle size. (2) Tap density: In accordance with JIS Z-2504, 100 g of filler was precisely weighed, put into a measuring cylinder with a funnel, tapped 600 times at a drop of 20 mm and a speed of 60 times / minute, and the weight of the charged 100 g and 600 times. It calculated | required in conversion from the volume which the graduated cylinder after a tap shows.

(3) Relative density: Calculated by (tap density / true density) × f × 100. However, f is a correction coefficient by an actual measurement value.

(4) Viscosity: Using an EHD type rotational viscometer (manufactured by Tokyo Keiki Seisakusho), the viscosity was measured at 25 ° C. at rotation speeds of 0.5 rpm and 5 rpm, and each measurement value was multiplied by a correction coefficient.

(5) Thixo value: calculated from the ratio of the viscosity at a rotation speed of 0.5 rpm to the viscosity at the rotation speed of 5 rpm.

(6) Die shear strength: About 0.2 mg of the adhesive composition was applied on a palladium plated lead frame (PPF, land portion: 10 mm × 8 mm), and a 2 mm × 2 mm silicon chip (thickness 0.4 mm) was formed thereon. Then, heat treatment was performed at 180 ° C. for 1 hour in a clean oven (Espec Corp.). A universal bond tester (manufactured by Daisy Corporation, 4000 series) was used to measure the shear strength (MPa) after heating at 200 ° C. and 260 ° C. for 30 seconds at a measurement speed of 500 μm / s and a measurement height of 120 μm.

(7) Thermal conductivity of cured product of adhesive composition: The adhesive composition was heat treated at 180 ° C. for 1 hour to obtain a 10 mm × 10 mm × 1 mm test piece. The thermal diffusivity of this test piece was measured by a laser flash method (manufactured by Netch, LFA 447, 25 ° C.), and the thermal diffusivity and the ratio obtained with a differential scanning calorimeter (Pyris 1 manufactured by PerkinElmer) From the product of the heat capacity and the specific gravity obtained by the Archimedes method, the cured product thermal conductivity (W / m · K) of the adhesive composition at 25 ° C. was calculated.

  The adhesive compositions of Examples 1 to 6 have a viscosity excellent in workability, and can improve the thermal conductivity while maintaining the adhesive strength. The adhesive composition of Comparative Example 1 having a low tap density has increased viscosity and reduced workability. In the adhesive compositions of Comparative Examples 2 to 3 using a single-shaped filler, a sufficient tap density cannot be obtained, the viscosity increases, and the workability decreases. In the adhesive composition of Comparative Example 4 containing no solvent, the viscosity increases and the thermal conductivity of the cured product decreases. The adhesive composition of Comparative Example 5 containing a solvent having a high evaporation rate has an increased viscosity and does not improve the thermal conductivity of the cured product. The adhesive composition of Comparative Example 6 containing a solvent having a high boiling point does not improve the thermal conductivity of the cured product.

It is sectional drawing of an example of the semiconductor device using the adhesive composition of this invention. It is another example sectional drawing of the semiconductor device using the adhesive composition of this invention.

Explanation of symbols

1 Semiconductor device (chip)
2 Support elements for semiconductor element mounting (lead frames)
3 Adhesive Layer Consisting of Adhesive Composition of the Present Invention 4 Wire 5 Sealing Material 6 Semiconductor Element Mounting Support Member (Glass Epoxy Substrate)
7 Electrode 8 Semiconductor element (LED chip)
9 Translucent sealing material

Claims (3)

An adhesive composition comprising a filler (A), a solvent (B) and a binder (C),
The filler (A) has a tap density of 6.5 g / cm ³ or more and 8.5 g / cm ³ or less, and is a mixed powder of a spherical or substantially spherical filler and a flat filler,
The solvent (B) has a boiling point of 150 ° C. or more and 260 ° C. or less, and an evaporation rate when the evaporation rate of n-butyl acetate at 25 ° C. and 55% RH is 100 or less (excluding 0). Yes, an adhesive composition, wherein the blending amount with respect to the binder (C) is 5% or more and 100% or less by volume ratio.   The adhesive composition according to claim 1, wherein the viscosity at 25 ° C at a rotation speed of 0.5 rpm is 70 Pa · s or more and 200 Pa · s or less.   A semiconductor device formed by bonding a semiconductor element and a support member for mounting a semiconductor element using the adhesive composition according to claim 1.