Addition-curable silicone resin composition and die attach material for semiconductor device

Abstract

To provide a silicone composition that achieves both of thermal conductivity and reduced elasticity.SOLUTION: A silicone composition includes: (A-1) branched polysiloxane represented by a formula (R11R22SiO1 / 2)a(R23SiO1 / 2)b(R22SiO2 / 2)c(R2SiO3 / 2)d(SiO4 / 2)e (R1 is an alkenyl group, R2 is an alkyl group, 0.01<a<0.15, 0.3<b<0.6, 0.25<e<0.67), (A-2) linear polysiloxane represented by a formula (R1R22SiO1 / 2)2(R22SiO2 / 2)x(R32SiO2 / 2)y (R3 is an aryl group, x>0, y≥0, 0.85≤(x / (x+y))), (B) linear polysiloxane represented by a formula (R23SiO1 / 2)2(HR2SiO2 / 2)j(R22SiO2 / 2)k(0.60≤(j / (j+k))≤0.95), (C) a catalyst, and (D) a thermally conductive filler in a flake shape having an average particle size of 3 μm or more. The silicone composition yields a cured product having thermal conductivity of 1.0 W / m K or more and a storage elastic modulus at -40°C of 150 MPa or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an addition-curable silicone resin composition and a die attach material for semiconductor devices. [Background technology]

[0002] Addition-curable silicone resins used as die attach agents in the electronic materials field have been attracting attention in recent years due to their advantages over conventional organic polymer resins such as epoxy resins and acrylic resins, such as high reliability in terms of moisture resistance and heat resistance, high stress relaxation capacity due to the ability to reduce elasticity, and easy handling.

[0003] For semiconductor applications, when mounting MEMS sensors or CMOS image sensors on a substrate, sensor die attach adhesives are required to reduce the transmission of impacts from the substrate to the chip and to mitigate stress over a wide operating temperature range. Methylphenyl silicone resins that harden into a gel or rubber state and have a low phenyl group content as a substituent are known to have a glass transition temperature of -50°C or below and very little change in storage modulus over a wide temperature range, making them ideal for use as die attach agents for the above sensors.

[0004] In recent years, due to the increasing heat generation caused by the larger chip size, particularly in CMOS image sensors, die attach adhesives are also required to have thermal conductivity. To impart thermal conductivity to die attach adhesives, a common approach is to heavily load a thermally conductive filler into the silicone resin. However, this increases the storage modulus of the cured product, raising concerns about increased warping of the sensor chip (Patent Document 1). On the other hand, if the silicone resin itself is formulated with a low modulus of elasticity so that the cured product becomes a gel, a low modulus of elasticity can be achieved even with a high loading of thermally conductive filler, but this raises concerns about reduced strength for holding the sensor chip (Patent Document 2).

[0005] Furthermore, silicone resins containing large amounts of highly volatile low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less are known to cause various problems when used as die attach agents for sensors. In particular, with CMOS image sensors, if low-molecular-weight siloxane compounds volatilized during processes subject to heat, such as the die attach agent curing process or reflow, adhere to the on-chip lens formed on the top surface of the chip, they can interfere with the incident light reaching the color filter during operation of the completed package, raising the risk of malfunction. Therefore, there is a demand for a low content of low-molecular-weight siloxanes with a degree of polymerization of 10 or less in the overall resin.

[0006] As described above, when conventional thermally conductive addition-curable silicone resin compositions are used as die attach agents for semiconductors, it is difficult to achieve both thermal conductivity and low elasticity while still achieving high resin strength in the cured product. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent Publication No. 2015-093970 [Patent Document 2] Patent Publication No. 2013-124257 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the above problems, and has an object to provide an addition-curable silicone resin composition that provides excellent resin strength in the cured product, and that combines thermal conductivity with low elasticity, and that also has excellent adhesion to substrates. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides an addition-curable silicone resin composition, comprising: (A-1) The following formula (1) (R 1 1R2 2SiO 1 / 2 ) a (R 2 3SiO 1 / 2 ) b (R 2 2SiO 2 / 2 ) c (R 2 SiO 3 / 2 ) d (SiO 4 / 2 ) e (1) (where R 1 is an alkenyl group having 2 to 8 carbon atoms, R 2 are independently alkyl groups having 1 to 12 carbon atoms, 0.01 < a < 0.15, 0.3 < b < 0.6, 0 ≦ c, 0 ≦ d, 0.25 < e < 0.67, provided that a + b + c + d + e = 1 is a number that satisfies this condition.) is a branched organopolysiloxane represented by and having two or more alkenyl groups having 2 to 8 carbon atoms in one molecule, (A-2) The following formula (2) (R 1 R 2 2SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) x (R 3 2SiO 2 / 2 ) y (2) (where R 1 and R 2 are the same as above respectively, R 3 is an aryl group having 6 to 12 carbon atoms independently, x and y are such that x > 0, y ≧ 0, 0.85 ≦ (x / (x + y)), and moreover, 50 ≦ x + y ≦ 5000 is a number that satisfies this condition.) is a linear organopolysiloxane represented by (B) The following formula (3) (R 2 3SiO 1 / 2 )2(HR 2 SiO 2 / 2 )<0^000034>(R 2 2SiO 2 / 2 ) k (3) (where R 2are the same as above, and j and k are positive numbers satisfying 0.60≦(j / (j+k))≦0.95, and 30≦j+k≦120, and the content of hydrosilyl group-containing organosilicon compounds having 1 to 10 silicon atoms is 5% by mass or less; (C) an addition cure catalyst, and (D) A flake-shaped thermally conductive filler having an average particle size (D50) of 3 μm or more. An addition-curable silicone resin composition comprising: The cured product of the addition-curable silicone resin composition has a thermal conductivity of 1.0 W / m·K or more and a storage modulus at −40°C of 150 MPa or less.

[0010] Such an addition-curable silicone resin composition can provide an addition-curable silicone resin composition that has excellent resin strength in the cured product, and that has both thermal conductivity and low elasticity.

[0011] Furthermore, the component (D) is preferably silver particles.

[0012] With such an addition-curable silicone resin composition, it is possible to obtain an addition-curable silicone resin composition that achieves both higher thermal conductivity and lower elasticity.

[0013] The addition-curable silicone resin composition of the present invention further contains, as an adhesion promoter (E), a compound represented by the following formula (4): (MeSiO 3 / 2 ) p1 (EpSiO 3 / 2 ) p2 (EpMeSiO 2 / 2 ) q1 (MeSiO 2 / 2 ) q2 (ViMeSiO 2 / 2 ) q3 (OR 5 ) r (4) (In the formula, Me is a methyl group, Ep is a monovalent organic group having an epoxy group, Vi is a vinyl group, and R 5 is an alkyl group having 1 to 12 carbon atoms, 0 ≦ p1 < 0.35, 0 ≦ p2 < 0.35, 0 ≦ q1 < 0.35, 0.4 ≦ q2 < 0.7, 0 < q3 < 0.1, 0 ≦ r < 0.05, and 0.15 ≦ (p2 + q1) / (p1 + p2 + q1 + q2 + q3 + r) ≦ 0.35, provided that p1 + p2 + q1 + q2 + q3 + r = 1.) It preferably contains a branched organopolysiloxane represented by , having a weight average molecular weight of 1,500 to 8,000 and an epoxy equivalent of 250 to 500 g / eq.)

[0014] With such an addition-curable silicone resin composition, an addition-curable silicone resin cured product excellent in adhesion to various base materials represented by an organic substrate can be obtained.)

[0015] Further, the addition-curable silicone resin composition of the present invention preferably further contains an inorganic filler as the component (F).)

[0016] In the addition-curable silicone resin composition of the present invention, for the purpose of improving the strength of the obtained cured product, imparting thixotropy to improve the coating workability of the die attach material, and suppressing the sedimentation of the thermal conductivity filler during storage, an inorganic filler can be appropriately blended.)

[0017] Further, it is preferable that the amount of the low molecular siloxane compound having a polymerization degree of 10 or less in the whole addition-curable silicone resin composition is 1% by mass or less.)

[0018] With such an addition-curable silicone resin composition, there is little adhesion of contaminants to peripheral members during curing, and defects in customer processes can be suppressed.)

[0019] Further, the present invention provides a die attach material for a semiconductor device comprising the above addition-curable silicone resin composition.)

[0020] Such a die attach material for semiconductor devices can provide a highly reliable semiconductor device because it has both high thermal conductivity and low elasticity while maintaining high resin strength after curing. [Effects of the Invention]

[0021] The addition-curable silicone resin composition of the present invention, when used as a die-attach material for semiconductor devices, can provide an addition-curable silicone resin composition that exhibits excellent resin strength in the cured product, achieves both thermal conductivity and low elasticity, and also exhibits excellent adhesive properties. For this reason, the addition-curable silicone resin composition of the present invention is extremely useful as a die-attach material for semiconductor devices.

[0022] The reason for this effect is thought to be that, by using the specific organopolysiloxanes in the specific combinations described above, both thermal conductivity and low elasticity are achieved while the resin strength of the cured product is excellent, compared to addition-curable silicone resin compositions containing ordinary thermally conductive fillers. DETAILED DESCRIPTION OF THE INVENTION

[0023] As described above, there has been a need for the development of an addition-curable silicone resin composition that provides excellent resin strength in the cured product, and that also has both thermal conductivity and low elasticity, as well as excellent adhesion to substrates.

[0024] As a result of extensive research into the above-mentioned problems, the present inventors discovered that by using specific organopolysiloxanes in specific combinations, it is possible to achieve both thermal conductivity and low elasticity while maintaining excellent resin strength in the cured product, as compared to addition-curable silicone resin compositions containing ordinary thermally conductive fillers, and thus completed the present invention.

[0025] That is, the present invention provides an addition-curable silicone resin composition, (A-1) The following formula (1) (R 1 1R 2 2SiO 1 / 2 ) a (R2 3SiO 1 / 2 ) b (R 2 2SiO 2 / 2 ) c (R 2 SiO 3 / 2 ) d (SiO 4 / 2 ) e (1) (wherein, R 1 is an alkenyl group having 2 to 8 carbon atoms, R 2 are each independently an alkyl group having 1 to 12 carbon atoms, and a satisfies 0.01 < a < 0.15, b satisfies 0.3 < b < 0.6, c satisfies 0 ≦ c, d satisfies 0 ≦ d, and e satisfies 0.25 < e < 0.67, provided that a + b + c + d + e = 1.) and is a branched organopolysiloxane having two or more alkenyl groups having 2 to 8 carbon atoms in one molecule, (A-2) The following formula (2) (R 1 R 2 2SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) x (R 3 2SiO 2 / 2 ) y (2) (wherein, R 1 and R 2 are the same as above respectively, R 3 is an aryl group having 6 to 12 carbon atoms independently, x and y satisfy x > 0, y ≧ 0, 0.85 ≦ (x / (x + y)), and 50 ≦ x + y ≦ 5000.) and is a linear organopolysiloxane represented by (B) The following formula (3) (R 2 3SiO 1 / 2 )2(HR 2 SiO 2 / 2 ) j (R 2 2SiO 2 / 2 ) k (3) (wherein, R 2are the same as above, and j and k are positive numbers satisfying 0.60≦(j / (j+k))≦0.95, and 30≦j+k≦120, and the content of hydrosilyl group-containing organosilicon compounds having 1 to 10 silicon atoms is 5% by mass or less; (C) an addition cure catalyst, and (D) A flake-shaped thermally conductive filler having an average particle size (D50) of 3 μm or more. An addition-curable silicone resin composition comprising: The cured product of the addition-curable silicone resin composition has a thermal conductivity of 1.0 W / m·K or more and a storage modulus at −40° C. of 150 MPa or less.

[0026] The present invention will be described in detail below, but the present invention is not limited thereto.

[0027] The addition-curable silicone resin composition of the present invention contains the above components (A-1) to (D), and may further contain various known additives as necessary. Each component will be described below.

[0028] <(A-1) Branched Organopolysiloxane> The component (A-1) is represented by the following formula (1), and is a branched organopolysiloxane having two or more alkenyl groups having 2 to 8 carbon atoms per molecule. (R 1 1R 2 2SiO 1 / 2 ) a (R 2 3SiO 1 / 2 ) b (R 2 2SiO 2 / 2 ) c (R 2 SiO 3 / 2 ) d (SiO 4 / 2 ) e (1) (In the formula, R 1is an alkenyl group having 2 to 8 carbon atoms, R 2 is independently an alkyl group having 1 to 12 carbon atoms, 0.01 < a < 0.15, 0.3 < b < 0.6, 0 ≦ c, 0 ≦ d, 0.25 < e < 0.67, provided that the numbers satisfy a + b + c + d + e = 1.)

[0029] In the above formula (1), R 1 As the alkenyl group having 2 to 8 carbon atoms, particularly 2 to 6 carbon atoms, specifically, vinyl group, allyl group, isopropenyl group, butenyl group, pentenyl group, hexenyl group, cyclohexenyl group, etc. are exemplified, and particularly the vinyl group is preferred.)

[0030] In the above formula (1), R 2 As the alkyl group having 1 to 12 carbon atoms, particularly preferably 1 to 10 carbon atoms, specifically, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert - butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, octyl group, nonyl group, decyl group, etc. can be exemplified. As the above R 2 Regarding the alkyl group, considering the heat resistance of the silicone cured product produced from the obtained addition - curable silicone resin composition under high - temperature conditions, alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group are preferred, and particularly the methyl group is preferred.)

[0031] Also, in the above formula (1), the content ratio a of R 1 1R 2 2SiO 1 / 2 units is in the range of 0.01 < a < 0.15 with respect to the total of the siloxane units a + b + c + d + e = 1, preferably in the range of 0.03 ≦ a ≦ 0.13. Also, the content ratio b of R 2 3SiO 1 / 2 units is 0.3 < b < 0.6 with respect to the total of the siloxane units a + b + c + d + e = 1, preferably in the range of 0.35 ≦ b ≦ 0.5. Further, the content ratio e of SiO 4 / 2 units is 0.25 < e < 0.67 with respect to the total of the siloxane units a + b + c + d + e = 1, preferably in the range of 0.3 ≦ e ≦ 0.6.)

[0032] In addition, R in the above formula (1) 2 2SiO 2 / 2 The above content ratios of units c and R 2 SiO 3 / 2 The content d of the units is an arbitrary unit, and 0≦c and 0≦d, respectively, where the total of the siloxane units is a+b+c+d+e=1. c is preferably 0, and d is preferably 0≦d≦30.

[0033] The component (A-1) can be easily synthesized by mixing compounds serving as the source units in the above-mentioned ranges and carrying out co-hydrolysis and condensation in the presence of an acid, for example.

[0034] Here, the above R 1 1R 2 2SiO 1 / 2 Examples of the unit source include organosilicon compounds such as triorganochlorosilane, triorganoalkoxysilane, and hexaorganodisiloxane, which are represented by the following structural formulas. 1 1R 2 2SiO 1 / 2 The unit sources are not limited to these.

[0035] [ka]

[0036] Here, the above R 2 3SiO 1 / 2 Examples of the unit source include organosilicon compounds such as triorganochlorosilane, triorganoalkoxysilane, and hexaorganodisiloxane, which are represented by the following structural formulas. 2 3SiO 1 / 2 The unit sources are not limited to these.

[0037] [ka]

[0038] Here, the SiO 4 / 2Examples of the unit source include organic silicon compounds such as tetrachlorosilane and tetraalkoxysilane represented by the following structural formula. 4 / 2 The unit sources are not limited to these.

[0039] [ka]

[0040] There are no particular limitations on the molecular weight of component (A-1), and for example, the weight average molecular weight as measured by GPC can be 1,000 to 20,000, preferably 2,000 to 10,000. Furthermore, component (A-1) may be either solid or liquid at 25°C.

[0041] <(A-2) Linear Organopolysiloxane> The component (A-2) is represented by the following formula (2), and has two R 1 It is a linear organopolysiloxane having an alkenyl group having 2 to 8 carbon atoms. (R 1 R 2 2SiO 1 / 2 )2(R 2 2SiO 2 / 2 ) x (R 3 2SiO 2 / 2 ) y (2) (In the formula, R 1 and R 2 are the same as above, and R 3 are independently an aryl group having 6 to 12 carbon atoms, and x and y are numbers such that x>0, y≧0, 0.85≦(x / (x+y)), and 50≦x+y≦5000.

[0042] In the above formula (2), R 1 Specific examples of alkenyl groups having 2 to 8 carbon atoms, particularly preferably 2 to 6 carbon atoms, include vinyl groups, allyl groups, isopropenyl groups, butenyl groups, pentenyl groups, hexenyl groups, and cyclohexenyl groups, with vinyl groups being particularly preferred.

[0043] In the above formula (2), R 2 Specific examples of alkyl groups having 1 to 12 carbon atoms, particularly 1 to 10 carbon atoms, include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl. 2 As the alkyl group, in consideration of the heat resistance under high temperature conditions of the silicone cured product produced from the resulting addition-curable silicone resin composition, alkyl groups such as methyl, ethyl, propyl, and isopropyl groups are preferred, and methyl groups are particularly preferred.

[0044] In the above formula (2), R 3 Specific examples of the aryl group having 6 to 12 carbon atoms include a phenyl group and a naphthyl group, with a phenyl group being particularly preferred. When a linear organopolysiloxane having a predetermined number of phenyl groups introduced therein is used, the storage modulus of the resulting addition-curable silicone resin cured product can be kept low in the low-temperature range.

[0045] In the above formula (2), x is x>0, preferably 85 to 3400, and y is y≧0, preferably 0 to 600, more preferably 8 to 600. Furthermore, x and y are numbers that satisfy 50≦x+y≦5000, and preferably 100≦x+y≦4000. Furthermore, 0.85≦(x / (x+y)), and preferably 0.90≦(x / (x+y)). Within the above ranges, compatibility with component (A-1) and the component (B) described below is good, and an addition-curable silicone resin cured product with high resin strength is obtained.

[0046] The component (A-2) is preferably in a liquid state at 25°C, and more preferably has a viscosity at 25°C of 8 to 30,000 mPa·s as measured with a rotational viscometer according to the method described in JIS K 7117-1:1999.

[0047] Specific examples of the component (A-2) include the following:

[0048] [ka]

[0049] The amount of component (A-2) blended is, for example, 100 to 3,000 parts by mass, preferably 100 to 2,000 parts by mass, more preferably 100 to 1,000 parts by mass, even more preferably 150 to 950 parts by mass, and extremely preferably 200 to 900 parts by mass, per 100 parts by mass of component (A-1).

[0050] <(B) Linear organohydrogenpolysiloxane> Component (B) is a linear organohydrogenpolysiloxane represented by the following formula (3). (R 2 3SiO 1 / 2 )2(HR 2 SiO 2 / 2 ) j (R 2 2SiO 2 / 2 ) k (3) (In the formula, R 2 are the same as above, j and k are positive numbers such that 0.60≦(j / (j+k))≦0.95, and 30≦j+k≦120.

[0051] Furthermore, the content of the hydrosilyl group-containing organosilicon compound having 1 to 10 silicon atoms in component (B) is no more than 5% by mass, and preferably no more than 1% by mass.

[0052] The above-mentioned component (B) acts as a crosslinking agent, and a cured silicone product is formed from the addition-curable silicone resin composition of the present invention by an addition reaction between alkenyl groups (particularly preferably vinyl groups) bonded to silicon atoms in the above-mentioned components (A-1) and (A-2) and hydrogen atoms (hydrosilyl groups) bonded to silicon atoms in the component (B).

[0053] HR in the above formula (3) 2 SiO 2 / 2Unit content j and R 2 2SiO 2 / 2 The relationship of the unit content k is in the range of 0.60≦(j / (j+k))≦0.95, preferably 0.70≦(j / (j+k))≦0.90, and 30≦j+k≦120, preferably 40≦j+k≦110.

[0054] In the above formula (3), R 2 are the same as above. 2 In consideration of the heat resistance of the cured silicone product produced from the resulting addition-curable silicone resin composition when left at high temperatures for an extended period of time, alkyl groups such as methyl, ethyl, propyl, and isopropyl are preferred as the alkyl group, with methyl being particularly preferred.

[0055] Because such linear organohydrogenpolysiloxanes contain a large number of siloxane units with silicon-bonded hydrogen atoms on the D units, the curing properties can be adjusted by steric hindrance during the addition curing reaction. Furthermore, they have high wettability with substrates, and any hydrosilyl groups that remain unincorporated into the addition curing reaction with alkenyl groups due to steric hindrance can be converted to hydroxysilyl groups by the addition reaction catalyst, contributing to improved adhesion to substrates.

[0056] Furthermore, the amount of hydrosilyl groups in the linear organohydrogenpolysiloxane of component (B) is preferably 0.7 to 1.5 mol / 100 g, and more preferably 1.0 to 1.4 mol / 100 g.

[0057] Specific examples of the linear organohydrogenpolysiloxane of component (B) include the following: [ka] (wherein j and k are the same as above.)

[0058] The amount of component (B) blended is preferably such that the total number of silicon-bonded hydrogen atoms in component (B) is in the range of 1.0 to 2.0 moles, and particularly preferably 1.1 to 1.5 moles, per mole of silicon-bonded alkenyl groups in the entire addition-curable silicone resin composition. When the total number of silicon-bonded hydrogen atoms in component (B) is within this range, the curing reaction proceeds smoothly, and a silicone cured product can be obtained with high adhesion to the substrate.

[0059] <(C) Addition curing catalyst> The addition curing catalyst of component (C) is blended to promote the addition curing reaction of the addition-curable silicone resin composition of the present invention and is available in platinum, palladium, and rhodium types. However, from the standpoint of cost and other factors, examples include platinum, platinum-based catalysts such as chloroplatinic acid, for example, HPtCl·mH2O, KPtCl·mH2O, KHPtCl·mH2O, KPtCl·mH2O, KPtCl·mH2O (m is a positive integer), and complexes of these with hydrocarbons such as olefins, alcohols, or alkenyl-group-containing organopolysiloxanes, which can be used alone or in combination of two or more. Furthermore, platinum-based catalysts may also be used that become active when exposed to ultraviolet light due to ligand cleavage.

[0060] The amount of addition curing catalyst blended is preferably in the range of 0.1 to 60 ppm, more preferably 1 to 50 ppm, in platinum group metal mass units, per 100 parts by mass of the entire addition curable silicone resin composition. When the amount of addition curing catalyst blended is within this range, the addition curable silicone resin composition has good storage properties and the addition curing reaction proceeds smoothly when heated.

[0061] <(D) Thermally conductive filler> Component (D), a flake-shaped thermally conductive filler with an average particle size (D50) of 3 μm or greater, is blended to improve the thermal conductivity of the addition-curable silicone resin composition of the present invention; specifically, it refers to a filler with a thermal conductivity of 20 W / m·K or greater. Inorganic substances and metals can be selected as the thermally conductive filler material. The use of flake-shaped silver particles is preferred because they maintain a low storage modulus for the cured product obtained from the addition-curable silicone composition and have high thermal conductivity.

[0062] The particle size of the thermally conductive filler can be selected depending on the film thickness when mounted for the intended use. When used as a die attach material for semiconductor devices, the average particle size is preferably 3 to 10 μm, more preferably 4 to 8 μm. In the present invention, the average particle size (D50) refers to the median diameter on a volume basis measured by laser diffraction.

[0063] The amount of thermally conductive filler blended is preferably in the range of 65 to 90 parts by mass, and more preferably 70 to 85 parts by mass, per 100 parts by mass of the total addition-curable silicone resin composition. When the blending amount of thermally conductive filler is within this range, the cured product obtained from the addition-curable silicone resin composition will have a low storage modulus and will exhibit high cured product strength and thermal conductivity.

[0064] <(E) Adhesion aid> In addition to the components (A-1) to (D), an adhesion promoter may also be added to the addition-curable silicone resin composition of the present invention.

[0065] The adhesive aid of component (E) is blended to more favorably exhibit adhesion to a substrate when the addition-curable silicone resin composition of the present invention is cured. It is a branched organopolysiloxane represented by the following formula (4), having a weight-average molecular weight of 1,500 to 8,000 and an epoxy equivalent of 250 to 500 g / eq. (MeSiO 3 / 2 ) p1 (EpSiO 3 / 2 ) p2 (EpMeSiO2 / 2 ) q1 (Me2SiO 2 / 2 ) q2 (ViMeSiO 2 / 2 ) q3 (OR 5 ) r (4) (In the formula, Me is a methyl group, Ep is a monovalent organic group having an epoxy group, Vi is a vinyl group, and R 5 is an alkyl group having 1 to 12 carbon atoms. For the molar fractions (contents) p1 to r of the repeating units, 0 ≦ p1 < 0.35, 0 ≦ p2 < 0.35, 0 ≦ q1 < 0.35, 0.4 ≦ q2 < 0.7, 0 < q3 < 0.1, 0 ≦ r < 0.05, and 0.15 ≦ (p2 + q1) / (p1 + p2 + q1 + q2 + q3 + r) ≦ 0.35, provided that p1 + p2 + q1 + q2 + q3 + r = 1.)

[0066] In the above formula (4), specific examples of the monovalent organic group having an epoxy group represented by Ep include organic groups such as 3-glycidoxypropyl group, 2-(3,4-epoxycyclohexyl)ethyl group, 5,6-epoxyhexyl group, 7,8-epoxyoctyl group, etc. Particularly, from the viewpoint of storage stability in the state of being blended in the addition-curable silicone resin composition, Ep is preferably a 3-glycidoxypropyl group. Also, as the alkyl group having 1 to 12 carbon atoms of R 5 , a methyl group is particularly preferred.)

[0067] Thus, the branched organopolysiloxane having a large weight-average molecular weight and a small epoxy equivalent has a large polarity difference from the component (A-1) and the component (A-2), and thus easily migrates to the interface with the substrate during curing, so that good adhesiveness can be exhibited. Further, since it has a vinyl group on the D unit, it is incorporated into the addition-curable silicone resin composition by an addition curing reaction, so that bleed-out after curing can be suppressed. Furthermore, compared with those having a vinyl group on the M unit, it is mildly incorporated into the composition, so that sufficient room for accommodation with the substrate can be provided.)

[0068] Also, MeSiO in the above formula (4)3 / 2 The above content fraction p1 of the unit ranges from 0 ≦ p1 < 0.35, particularly preferably from 0 ≦ p1 ≦ 0.3, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Also, EpSiO 3 / 2 The above content fraction p2 of the unit ranges from 0 ≦ p2 < 0.35, particularly preferably from 0 ≦ p2 ≦ 0.3, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Further, EpMeSiO 2 / 2 The above content fraction q1 of the unit ranges from 0 ≦ q1 < 0.35, particularly preferably from 0 ≦ q1 ≦ 0.3, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Also, Me2SiO 2 / 2 The above content fraction q2 of the unit is 0.4 ≦ q2 < 0.7, particularly preferably in the range of 0.45 ≦ q2 ≦ 0.65, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Also, ViMeSiO 2 / 2 The above content fraction q3 of the unit is 0 < q3 < 0.1, particularly preferably in the range of 0 < q3 ≦ 0.08, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Further, OR 5 The above content fraction r of the unit is 0 ≦ r < 0.05, particularly preferably in the range of 0 ≦ r ≦ 0.03, with respect to the total of the siloxane units p1 + p2 + q1 + q2 + q3 + r = 1. Also, 0.15 ≦ (p2 + q1) / (p1 + p2 + q1 + q2 + q3 + r) ≦ 0.35.

[0069] Also, the weight average molecular weight of the branched organopolysiloxane of the above formula (4) is in the range of 1,500 to 8,000, preferably in the range of 2,000 to 7,500. If the weight average molecular weight is 8,000 or less, there is no risk that the appearance of the silicone resin cured product will become cloudy, and if the weight average molecular weight is 1,500 or more, sufficient adhesion to the substrate can be obtained. The weight average molecular weight Mw referred to in the present invention shall refer to the weight average molecular weight using polystyrene as a standard substance by gel permeation chromatography (GPC) measured under the following conditions.

[0070] [Measurement Conditions] Developing solvent: tetrahydrofuran (THF) ·Flow rate: 0.6mL / min Detector: Refractive index detector (RI) Column: TSK Guardcol u mn SuperH-L ·TSKgel SuperH4000(6.0mmI.D.×15cm×1) ·TSKgel SuperH3000(6.0mmI.D.×15cm×1) ·TSKgel SuperH2000(6.0mmI.D.×15cm×2) (All manufactured by Tosoh Corporation) Column temperature: 40℃ Sample injection volume: 20 μL (0.5% by mass THF solution)

[0071] Furthermore, the epoxy equivalent of the branched organopolysiloxane of formula (4) is in the range of 250 to 500 g / eq, preferably 300 to 450 g / eq. If the epoxy equivalent is 500 g / eq or less, sufficient adhesion to the substrate can be obtained, and if the epoxy equivalent is 250 g / eq or more, there is no risk of separation from the silicone resin composition.

[0072] The component (E) can be easily synthesized by mixing the compounds serving as the source units in the above-mentioned ranges and carrying out co-hydrolysis and condensation in the presence of a base, for example.

[0073] Here, the above EpSiO 3 / 2 Unit source and EpMeSiO 2 / 2 Examples of the unit source include organosilicon compounds represented by the following structural formulas, but usable EpSiO 3 / 2 Unit source and EpMeSiO 2 / 2 The unit sources are not limited to these.

[0074] [ka]

[0075] The amount of component (E) blended is preferably in the range of 0.1 to 10 parts by mass, and particularly preferably in the range of 0.2 to 5 parts by mass, per 100 parts by mass of the total addition-curable silicone resin composition. If the amount of component (E) blended is 0.2 parts by mass or more, excellent adhesion to the substrate is achieved, and if it is 5 parts by mass or less, it can be used without problems in coating workability, and is therefore preferred.

[0076] <(F) Inorganic filler> The addition-curable silicone resin composition of the present invention can be appropriately blended with an inorganic filler for the purposes of improving the strength of the resulting cured product, imparting thixotropy to improve the application workability of the die attach material, and suppressing settling of the thermally conductive filler during storage. Examples of inorganic fillers include fumed silica and quartz powder, and the use of fumed silica is particularly preferred.

[0077] When an inorganic filler is blended, the blending amount is preferably 10% by mass or less, more preferably 0.1 to 5% by mass, based on 100% by mass of the entire silicone resin composition. In particular, when fumed silica is used as the inorganic filler, it is preferable that the silica surface be treated with a hydrophobic group from the viewpoint of compatibility with the silicone resin. Specific examples of the hydrophobic group include siloxane groups such as trimethylsilyl and dimethylsilyl groups.

[0078] Furthermore, the surface treatment also has the effect of suppressing the interaction between the epoxy groups contained in the component (E) and the hydroxysilyl groups on the surface of the fumed silica, thereby improving storage stability. For this reason, it is preferable that the fumed silica be sufficiently surface-treated, and specifically, fumed silica having a specific surface area of ​​150 m 2 / g or more 290m 2 / g or less, preferably 170m 2 / g or more 230m 2It is preferable to use fumed silica having a specific surface area of ​​230 to 290 m. As the fumed silica surface-treated with a siloxane-based functional group, a commercially available product is R812 (specific surface area: 230 to 290 m) surface-treated with a trimethylsilyl group, manufactured by Nippon Aerosil Co., Ltd. 2 / g) and RX300 (specific surface area 180-220 m 2 / g), R976 (specific surface area 225-275 m) surface-treated with dimethylsilyl groups 2 / g), R976S (specific surface area 215~265m 2 / g) etc.

[0079] <Cure inhibitor> The addition-curable silicone resin composition of the present invention can contain a cure inhibitor for the purpose of adjusting the cure rate, etc. Examples of cure inhibitors include vinyl group-containing organopolysiloxanes such as tetramethyltetravinylcyclotetrasiloxane, hexavinyldisiloxane, and 1,3-divinyltetramethyldisiloxane, acetylene alcohols such as ethynylcyclohexanol and 3-methyl-1-butyn-3-ol, and silane- or siloxane-modified versions thereof, hydroperoxides, tetramethylethylenediamine, benzotriazole, triallyl isocyanurate, alkyl maleates, and mixtures thereof.

[0080] When a cure inhibitor is added, it can be added preferably in an amount of 0.001 to 1.0 part by mass, and particularly preferably 0.005 to 0.5 part by mass, per 100 parts by mass of the total silicone resin composition.

[0081] <Low molecular weight siloxane compound> In the addition-curable silicone resin composition of the present invention, the amount of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less in the entire resin composition is preferably 1% by mass or less, and more preferably 0.5% by mass or less. If the amount of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less is equal to or less than this amount, it is possible to provide a semiconductor package that causes little contamination of surrounding components and does not impair operation.

[0082] The content of low molecular weight siloxane compounds having a degree of polymerization of 10 or less referred to in the present invention refers to the content of siloxane compounds determined by gas chromatography under the following conditions.

[0083] [Measurement conditions] Equipment: GC-2014 (Shimadzu Corporation) Column: Product name: HP-5MS (Agilent Technologies, Inc., inner diameter: 0.25 mm, length: 30 m, packing material: (5%-phenyl)-methylpolysiloxane) Detector: FID detector (detector temperature: 300°C) Sample: 1.0 g of sample was dissolved in 10 mL of n-tetradecane / acetone standard solution (concentration: 20 μg / mL) to prepare a sample. ·Injection volume: 1μL Oven temperature: 50℃-280℃ / 23 minutes-280℃ / 17 minutes Carrier gas: Type...Helium, Linear velocity...34.0cm / s

[0084] <Thermal conductivity> The addition-curable silicone resin composition of the present invention has a thermal conductivity of at least 1.0 W / m K, and preferably at least 1.5 W / m K, after curing. If the cured resin has a thermal conductivity of at least this value, when used as a semiconductor die attach agent, it can sufficiently dissipate heat generated by the semiconductor chip, thereby reducing the power consumption of the semiconductor package and preventing breakdowns.

[0085] In the present invention, the thermal conductivity of the cured product of the addition-curable silicone resin composition can be a value obtained using a resin material thermal resistance measuring device (manufactured by Hitachi Technology & Services), which uses a steady-state measurement principle.

[0086] <Storage modulus at -40℃> The addition-curable silicone resin composition of the present invention has a storage modulus of 150 MPa or less, and preferably 100 MPa or less, of the cured resin at −40° C. If the storage modulus of the cured resin at −40° C. is equal to or less than this value, warping of the semiconductor package in the operating temperature range is reduced, and operational malfunctions can be suppressed.

[0087] In the present invention, the storage modulus at −40° C. of the cured product of the addition-curable silicone resin composition can be a value measured using a dynamic viscoelasticity measuring apparatus (DMA) “Q800” manufactured by TA Instruments Japan, Inc.

[0088] The addition-curable silicone resin composition of the present invention can be applied to a substrate and then cured depending on the application. Heat curing can be carried out at a temperature of preferably 70 to 130°C, more preferably 90 to 1200°C. A heating temperature within the above range is preferred because it improves the adhesive strength between the substrate and the cured resin, making it possible to obtain a semiconductor package with minimal warping. The heat curing time may be 0.5 to 2.5 hours, and a step curing method may also be used.

[0089] The addition-curable silicone resin composition of the present invention uses the specific organopolysiloxanes in a specific combination, thereby providing an addition-curable silicone resin composition with superior resin strength compared to conventional addition-curable silicone resin compositions, making it suitable for use in electrical and electronic components, and specifically as a die attach material for semiconductor devices. [Example]

[0090] EXAMPLES The present invention will be specifically explained below using examples and comparative examples, but the present invention is not limited to these.

[0091] In the examples below, "parts" refers to "parts by mass," and Me represents "methyl group," Vi represents "vinyl group," and Ep' represents "γ-glycidoxypropyl group." The weight-average molecular weight refers to the weight-average molecular weight measured by GPC under the conditions described above. In the examples below, the amount of SiH groups refers to the number of moles of hydrogen atoms directly bonded to silicon atoms in the molecule, and is measured by a Bruker nuclear magnetic resonance (NMR) measurement device. 1 The value was determined by H-NMR measurement using dimethyl sulfoxide (DMSO) as an internal standard. The amount of SiVi groups indicates the number of moles of vinyl groups directly bonded to silicon atoms in the molecule, and was measured using a Bruker nuclear magnetic resonance (NMR) measurement device. 1 The values ​​were determined by H-NMR measurement using DMSO as an internal standard.

[0092] <Component (A-1)> (a1-1) : The siloxane unit is ViMe2SiO 1 / 2 10 mol% of units, Me3SiO 1 / 2 40 mol% of units, SiO 4 / 2 A branched organopolysiloxane that is solid at 25°C, expressed in units of 50 mol%, has an SiVi group content of 0.08 mol / 100 g, has a weight average molecular weight of 5,600 as measured by GPC, and contains 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less. (a1-2) : The siloxane unit is ViMe2SiO 1 / 2 10 mol% of units, Me3SiO 1 / 2 35 mol% of units, MeSiO 3 / 2 25 mol% of units, SiO 4 / 2 A branched organopolysiloxane that is liquid at 25°C, expressed in units of 30 mol%, has an SiVi group content of 0.09 mol / 100 g, has a weight average molecular weight of 4,900 as measured by GPC, and contains 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less.

[0093] <Component (A-2)> (a2-1) :The following formula (ViMe2SiO 1 / 2 )2(Ph2SiO 2 / 2 )20 (MeSiO 2 / 2 ) 350 A linear organopolysiloxane having a SiVi group content of 0.006 mol / 100 g, being liquid at 25°C, containing 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and having a viscosity of 5,100 mPa·s at 25°C. (a2-2) :The following formula (ViMe2SiO 1 / 2 )2(Me2SiO 2 / 2 ) 388 A linear organopolysiloxane having a SiVi group content of 0.006 mol / 100 g, being liquid at 25°C, containing 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and having a viscosity of 5,000 mPa·s at 25°C.

[0094] <(B) component> (b-1) :The following formula (MeSiO 1 / 2 )2(HMeSiO 2 / 2 ) 72 (MeSiO 2 / 2 ) 24 an organohydrogenpolysiloxane having a hydrosilyl group content of 1.14 mol / 100 g, being liquid at 25°C, containing 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and having a viscosity of 163 mPa·s at 25°C. (b-2) :The following formula (MeSiO 1 / 2 )2(HMeSiO 2 / 2 ) 86 (MeSiO 2 / 2 ) 10 an organohydrogenpolysiloxane having a hydrosilyl group content of 1.40 mol / 100 g, being liquid at 25°C, containing 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and having a viscosity of 165 mPa·s at 25°C.

[0095] <(C) component> (c-1) : A 1,3-divinyltetramethyldisiloxane solution of a 1,3-divinyltetramethyldisiloxane complex of platinum (0) having a platinum content of 2 mass% and an SiVi group content of 1.05 mol / 100 g

[0096] <(D) component> (d-1) : Flake silver powder "AgC-237" (Fukuda Metal Foil) with an average particle size (D50) of 6.5 μm pink Kogyosha) (d-2) : Flake silver powder "AgC-239" (Fukuda Metal Foil) with an average particle size (D50) of 2.4 μm pink Kogyosha) (for comparison) (d-3) : Flake silver powder "FA-D-1" (manufactured by DOWA Electronics Co., Ltd.) with an average particle size (D50) of 4.2 μm (d-4) : Flake silver powder "AgC-223" (Fukuda Metal Foil) with an average particle size (D50) of 7.6 μm pink Kogyosha) (d-5) : Spherical silver-plated copper core powder "TFM-C05P" (manufactured by Toyo Aluminum Co., Ltd.) with an average particle size (D50) of 6.1 μm (for comparison) (d-6) : Spherical aluminum oxide "AC-9204" (manufactured by Admatechs Co., Ltd.) with an average particle size (D50) of 5.7 μm (for comparison)

[0097] <(E) component> (e-1) : The siloxane unit is Ep'SiO 3 / 2 29 mol% Me2SiO 2 / 2 64 mol% ViMeSiO 2 / 2 A branched organopolysiloxane having 6 mol% OMe units and 1 mol% OMe units, a weight average molecular weight of 2,400, an SiVi group content of 0.05 mol / 100 g, an epoxy equivalent of 330 g / eq, which is liquid at 25°C, contains 0.3 mass% low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and has a viscosity at 25°C of 350 mPa·s. (e-2) : The siloxane unit is MeSiO3 / 2 25 mol% of units, Ep'MeSiO 2 / 2 22 mol% of units, Me2SiO 2 / 2 47 mol% ViMeSiO 2 / 2 A branched organopolysiloxane having 5 mol% OMe units and 1 mol% OMe units, a weight average molecular weight of 4,500, an SiVi group content of 0.05 mol / 100 g, an epoxy equivalent of 435 g / eq, which is liquid at 25°C, contains 0.1 mass% of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and has a viscosity at 25°C of 355 mPa s.

[0098] <(F) Component> (f-1) : Fumed silica "RX300" manufactured by Nippon Aerosil Co., Ltd.

[0099] <Cure inhibitor> (g-1) : Ethynylcyclohexanol

[0100] [Examples 1 to 8, Comparative Examples 1 to 5] The addition-curable silicone resin compositions of Examples 1 to 8 and Comparative Examples 1 to 5 were prepared according to the blending ratios (values ​​are in parts by mass) shown in Tables 1 and 2, and the compositions were evaluated for hardness, tensile strength, elongation at break, storage modulus of the cured product at -40°C, adhesion, thermal conductivity, content of low-molecular-weight siloxane compounds with a degree of polymerization of 10 or less, and storage stability using the test methods described below. The results of each measurement are shown in Tables 1 and 2.

[0101] (a) Hardness The addition-curable silicone resin composition was heated at 100°C for 1 hour using a hot air circulation dryer to produce a silicone cured product. The durometer of the silicone cured product was measured in accordance with JIS K 6253-3:2012 using a Type A durometer.

[0102] (b) Tensile strength, elongation at break The addition-curable silicone resin composition was heated in a hot air circulating dryer at 100°C for 1 hour to produce a silicone cured product. The tensile strength and elongation at break of the silicone cured product were measured in accordance with JIS K 6250.

[0103] (c) Storage modulus of cured product at -40°C The addition-curable silicone resin composition was heated in a hot air circulating dryer at 100°C for 1 hour to produce a 2 mm thick sheet of cured silicone. The storage modulus of the cured silicone material at -40°C was measured using a TA Instruments Japan Q800 dynamic viscoelasticity measuring device (DMA).

[0104] (d) Adhesiveness A predetermined amount of addition-curable silicone resin composition was applied to an FR-4 glass epoxy substrate, and a 3.0 mm x 3.0 mm Si chip was die-bonded to it. The composition was then heat-cured for 1 hour at 100°C using a hot air circulating dryer. After heating, the package was removed and cooled to 25°C. The adhesive strength between the chip and the substrate was measured using a bond tester (Nordson Advanced Technologies: Dage4000) for 50 tests for each cured resin, and the average adhesive strength was calculated.

[0105] (e) Thermal conductivity The addition-curable silicone resin composition was heated at 100°C for 1 hour using a hot air circulation dryer to produce sheet-shaped silicone cured products with thicknesses of 0.5 mm, 1 mm, and 2 mm.

[0106] The cured material of each thickness was cut into 10mm squares, and the thermal resistance value for each thickness was obtained using a resin material thermal resistance measuring device (manufactured by Hitachi Technology and Services), which uses the steady-state measurement principle (load: 100kPa). After plotting the three measurement results, an approximate curve was drawn using linear approximation, and the thermal conductivity of each cured resin was calculated from the slope of the linear approximation curve and the size of the cured material.

[0107] (f) Content of low molecular weight siloxane compounds with a degree of polymerization of 10 or less The content of low molecular weight siloxane compounds with a degree of polymerization of 10 or less in the addition-curable silicone resin composition was measured using the same method as described above.

[0108] (g) Storage stability The addition-curable silicone resin compositions were stored in a -20°C freezer for one month, and then thawed to room temperature, after which the surface condition was observed. Those in which no separation of the resin and filler was observed were marked with an "O", and those in which separation was observed were marked with an "X".

[0109] [Table 1]

[0110] [Table 2]

[0111] The above evaluation tests revealed that the addition-curable silicone resin compositions of the present invention (Examples 1 to 8) exhibited excellent resin strength and achieved both thermal conductivity and low modulus. In contrast, Comparative Example 1 exhibited a high storage modulus at -40°C and low thermal conductivity due to the average particle size (D50) of component (D) being less than 3 μm. Comparative Example 2 exhibited low thermal conductivity due to the absence of a thermally conductive filler. Comparative Example 3 did not contain component (A-1), resulting in very low strength and adhesiveness of the cured resin. Furthermore, in Comparative Example 4, component (D) was not in flake form, and component separation was observed during storage. In Comparative Example 5, component (D) was also not in flake form, resulting in an excessively high storage modulus at -40°C of the cured resin. Therefore, the addition-curable silicone resin compositions of the present invention exhibited excellent resin strength and achieved both thermal conductivity and low modulus, demonstrating their usefulness as die attach materials for semiconductor devices.

[0112] This specification includes the following inventions.

[0113] [1]: An addition-curable silicone resin composition, comprising (A-1) a branched organopolysiloxane represented by the following formula (1) (R 1 1R 2 2SiO 1 / 2 ) a (R 2 3SiO 1 / 2 ) b (R 2 2SiO 2 / 2 ) c (R 2 SiO 3 / 2 ) d (SiO 4 / 2 ) e (1) (wherein, R 1 is an alkenyl group having 2 to 8 carbon atoms, R 2 are each independently an alkyl group having 1 to 12 carbon atoms, 0.01 < a < 0.15, 0.3 < b < 0.6, 0 ≤ c, 0 ≤ d, 0.25 < e < 0.67, provided that a + b + c + d + e = 1. A branched organopolysiloxane having two or more alkenyl groups having 2 to 8 carbon atoms in one molecule), (A-2) a linear organopolysiloxane represented by the following formula (2) (R 1 R 2 2SiO 1 / 2 ])2(R 2 2SiO 2 / 2 ) x (R[[ID=??]] 3 2SiO?? 2 / 2 ) y (2) (wherein, R 1 and R 2 are the same as above, R 3 is an aryl group having independent carbon atoms of 6 to 12, x and y are x > 0, y ≥ 0, 0.85 ≤ (x / (x + y)), and 50 ≤ x + y ≤ 5000. A linear organopolysiloxane represented by), (B) the following formula (3) (R 2 3SiO​​​​​​​​​​​​​​are the same as above, and j and k are positive numbers satisfying 0.60≦(j / (j+k))≦0.95, and 30≦j+k≦120. An addition-curable silicone resin composition comprising: a linear organohydrogenpolysiloxane represented by the formula (I), wherein the content of a hydrosilyl group-containing organosilicon compound having 1 to 10 silicon atoms is 5% by mass or less; (C) an addition curing catalyst; and (D) a flake-shaped thermally conductive filler having an average particle size (D50) of 3 μm or more; wherein the cured product of the addition-curable silicone resin composition has a thermal conductivity of 1.0 W / m·K or more and a storage modulus at −40°C of 150 MPa or less.

[0114] [2]: The addition-curable silicone resin composition according to the above [1], wherein the component (D) is silver particles.

[0115] [3]: Furthermore, as an adhesive aid (E), a compound represented by the following formula (4) (MeSiO 3 / 2 ) p1 (EpSiO 3 / 2 ) p2 (EpMeSiO 2 / 2 ) q1 (MeSiO 2 / 2 ) q2 (ViMeSiO 2 / 2 ) q3 (OR 5 ) r (4) (wherein Me is a methyl group, Ep is a monovalent organic group having an epoxy group, Vi is a vinyl group, and R 5is an alkyl group having 1 to 12 carbon atoms, 0≦p1<0.35, 0≦p2<0.35, 0≦q1<0.35, 0.4≦q2<0.7, 0<q3<0.1, 0≦r<0.05, and 0.15≦(p2+q1) / (p1+p2+q1+q2+q3+r)≦0.35, provided that p1+p2+q1+q2+q3+r = 1. It is represented by (), has a weight average molecular weight of 1,500 to 8,000, and contains a branched organopolysiloxane having an epoxy equivalent of 250 to 500 g / eq. The addition-curable silicone resin composition according to the above [1] or [2], characterized in that it contains the above.

[0116] [4]: Further, the addition-curable silicone resin composition according to the above [1], [2], or [3], characterized in that it contains an inorganic filler as the (F) component.

[0117] [5]: The addition-curable silicone resin composition according to the above [1], [2], [3], or [4], characterized in that the amount of the low molecular weight siloxane compound having a degree of polymerization of 10 or less in the whole addition-curable silicone resin composition is 1% by mass or less.

[0118] [6]: A die attach material for a semiconductor device, characterized in that it is made of the addition-curable silicone resin composition according to the above [1], [2], [3], [4], or [5].

[0119] Note that the present invention is not limited to the above embodiments. The above embodiments are examples, and any configuration that has a substantially identical configuration to the technical idea described in the claims of the present invention and exhibits the same operational effects is included in the technical scope of the present invention.

Claims

1. An addition-curable silicone resin composition, comprising: (A-1) The following formula (1) (R １ １ R ２ ２ SiO １／２ ) ａ (R ２ ３ SiO １／２ ) ｂ (R ２ ２ SiO ２／２ ) ｃ (R ２ SiO ３／２ ) ｄ (SiO ４／２ ) ｅ (1) (In the formula, R １ is an alkenyl group having 2 to 8 carbon atoms, R ２ are independently an alkyl group having 1 to 12 carbon atoms, and are numbers satisfying the relationship: 0.01<a<0.15, 0.3<b<0.6, 0≦c, 0≦d, and 0.25<e<0.67, and a+b+c+d+e=1. and a branched organopolysiloxane having two or more alkenyl groups having 2 to 8 carbon atoms in one molecule, (A-2) The following formula (2) (R １ R ２ ２ SiO １／２ ) ２ (R ２ ２ SiO ２／２ ) ｘ (R ３ ２ SiO ２／２ ) ｙ (2) (In the formula, R １ and R ２ are the same as above, and R ３ are independently an aryl group having 6 to 12 carbon atoms, x is 85 to 3400, y is 8 to 600, and is a number satisfying 0.85≦(x / (x+y)) and 93≦x+y≦4000. a linear organopolysiloxane represented by the formula: (B) The following formula (3) (R ２ ３ Yes １／２ ) ２ (HR) ２ Yes ２／２ ) ｊ (R ２ ２ Yes ２／２ ) ｋ (3) (In the formula, R ２ are the same as above, and j and k are positive numbers satisfying 0.60≦(j / (j+k))≦0.95, and 30≦j+k≦120, in which the content of hydrosilyl group-containing organosilicon compounds having 1 to 10 silicon atoms is 5% by mass or less; (C) an addition cure catalyst, and (D) A flake-shaped thermally conductive filler having an average particle size (D50) of 3 μm or more. An addition-curable silicone resin composition comprising: The cured product of the addition-curable silicone resin composition has a thermal conductivity of 1.0 W / m K or more and a storage modulus at −40° C. of 150 MPa or less, and The blending amount of the component (A-2) is 100 to 3,000 parts by mass per 100 parts by mass of the component (A-1), An addition-curable silicone resin composition characterized in that the blend amount of component (B) is an amount such that the total number of silicon-bonded hydrogen atoms in component (B) is in the range of 1.0 to 2.0 moles per mole of total silicon-bonded alkenyl groups in the entire addition-curable silicone resin composition.

2. 2. The addition-curable silicone resin composition according to claim 1, wherein component (D) is silver particles.

3. Furthermore, as the adhesive aid (E), a compound represented by the following formula (4) (MeSi) ３／２ ) ｐ１ (EpSiO) ３／２ ) ｐ２ (Ep. Me. Si.) ２／２ ) ｑ１ (Me) ２ SiO ２／２ ) ｑ２ (Violet) ２／２ ) ｑ３ (OR) ５ ) ｒ (4) (In the formula, Me is a methyl group, Ep is a monovalent organic group having an epoxy group, Vi is a vinyl group, and R ５ represents an alkyl group having 1 to 12 carbon atoms, 0≦p1<0.35, 0≦p2<0.35, 0≦q1<0.35, 0.4≦q2<0.7, 0<q3<0.1, 0≦r<0.05, and 0.15≦(p2+q1) / (p1+p2+q1+q2+q3+r)≦0.35, provided that p1+p2+q1+q2+q3+r=1.

2. The addition-curable silicone resin composition according to claim 1, which contains a branched organopolysiloxane having a weight-average molecular weight of 1,500 to 8,000 and an epoxy equivalent of 250 to 500 g / eq.

4. 2. The addition-curable silicone resin composition according to claim 1, further comprising an inorganic filler as component (F).

5. The addition-curable silicone resin composition as a whole contains a low-molecular-weight siloxane compound having a degree of polymerization of 10 or less.

2. The addition-curable silicone resin composition according to claim 1, wherein the amount of the copolymer is 1% by weight or less.

6. A die attach material for semiconductor device, comprising the addition-curable silicone resin composition according to any one of claims 1 to 5.

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