KR20090101837A - Curable silicone rubber composition and semiconductor device - Google Patents

Abstract

PURPOSE: A curable silicone rubber composition is provided to ensure transparency and enough adhesion strength to thermoplastic plastic such as PPA and metal electrode. CONSTITUTION: A curable silicone rubber composition includes linear organopolysiloxane and resin-structured organopolysiloxane. The linear organopolysiloxaneis represented by chemical formula 1 and has 10 ~ 1,000,000 mPa·s of viscosity at 25 °C. The resin-structured organopolysiloxane comprises an SiO2 unit, R3kR4pSiO0.5 unit, and R3qR4rSiO0.5 unit.

Description

Curable Silicone Rubber Composition and Semiconductor Device {CURABLE SILICONE RUBBER COMPOSITION AND SEMICONDUCTOR DEVICE}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an addition-curable silicone rubber composition, in particular a thermoplastic silicone such as PPA (polyphthalic acid amide resin) and a liquid crystal polymer (LCP) and a curable silicone rubber composition having good adhesion to electrode noble metals such as silver and gold and the like. A semiconductor device sealed with cargo.

The silicone rubber composition is used for various applications because it forms a cured product having excellent properties such as weather resistance and heat resistance and rubber properties such as hardness and elongation.

 Recently, as thermoplastics having excellent heat resistance, PPA (polyphthalic acid amide resin), LCP (liquid crystal polymer) and the like have been examined as materials of various packages, and metals such as Ag, Au, Ni, Pd, etc. are used as the frame and electrode. have. However, it is difficult to firmly adhere silicone rubber to them. In addition, the solder conditions in the apparatus formed using these materials are changed to the high temperature solder which does not contain lead. Therefore, there arises a problem that peeling occurs easily at the interface between the package and the silicone resin due to preservation at high temperature stress, temperature cycle, and high temperature and high humidity. Moreover, the problem that a silicone resin deteriorates, hardens, and a crack generate | occur | produces by heat_generation | fever of LED (light emitting diode) arises (for example, refer patent document 1).

In general, in the addition-curable silicone rubber composition, the adhesion is improved by the addition of various silane coupling agents, but the coupling agent containing a large amount of epoxy groups has a high refractive index and impairs the transparency of the composition. In addition, if a strong reaction occurs, it becomes discolored, becomes cloudy, and is unsuitable for light use. Although the addition-curable silicone rubber composition of patent document 2 is excellent in adhesiveness with metals, such as Ag, Au, Ni, and Pd, from the viewpoint of discoloration resistance and light resistance, use as an optical use is insufficient.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2003-174059

[Patent Document 2] Japanese Patent Application Laid-Open No. 2007-002234

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and includes materials of various packages made of thermoplastics such as PPA (polyphthalic acid amide resin) and LCP (liquid crystal polymer), which are difficult to adhere, and metals such as Ag, Au, Ni, and Pd. It aims at providing the curable silicone rubber composition which provides sufficient adhesive strength also to the electrode which consists of, and provides the hardened | cured material which has favorable transparency, and the semiconductor device sealed by the hardened | cured material of this composition.

MEANS TO SOLVE THE PROBLEM As a result of earnestly examining in order to achieve the said objective, the curable silicone rubber composition whose difference in refractive index between predetermined organosiloxane components is below a predetermined value is the material of the various packages which consist of thermoplastic plastics, such as PPA and LCP. The semiconductor device sealed by the said hardened | cured material which has sufficient adhesive strength with respect to the board | substrate which is difficult to adhere | attaches, such as an electrode which consists of metals, such as Ag, Au, Ni, Pd, etc., is excellent in transparency, and is sealed It was found that this was excellent and came to complete this invention.

Accordingly, the present invention is a straight-chain organopolysiloxane (A-1) represented by the following general formula (A) having a viscosity of 10 to 1,000,000 mPa · s at 25 ° C., or

An organopolysiloxane (A-2) in the organopolysiloxane (A-1), a resin structure, SiO _{2 ^{units, R 3 k R 4 p SiO}} 0 .5 units and ^{_{R 3 q R 4 r SiO 0}} .5 Wherein, in the formula, R ³ is a vinyl or allyl group, R ⁴ is a monovalent hydrocarbon group containing no aliphatic unsaturated bonds, k is 2 or 3, p is 0 or 1, and k is + p = 3, q is 0 or 1, r is 2 or 3, q + r = 3) and a combination with organopolysiloxane,

(Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group independently of each other, R ² is an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bonds independently of each other, x and y are each 0 or a positive integer) And x + y is the number which makes the viscosity of 25 degreeC of this organopolysiloxane into 10-1,000,000 mPa * s, p is an integer of 1-3)

(B) organohydrogenpolysiloxane which has 2 or more SiH groups in 1 molecule,

(C) metal-based condensation reaction catalyst,

(D) a platinum group metal-based addition reaction catalyst and

(E) containing an organopolysiloxane adhesion imparting component containing two or more kinds of functional groups selected from alkenyl groups, alkoxy groups and epoxy groups,

It is a curable silicone rubber composition characterized by the difference of the maximum value and the minimum value of refractive index of each of (A) component, (A) component and (B) component, and (E) component each 0.03 or less. Moreover, this invention provides the semiconductor device which sealed the semiconductor chip with the hardened | cured material of this composition.

The curable silicone rubber composition of the present invention provides effective adhesion to substrates such as Ag and PPA, which have been very difficult to adhere until now, and the semiconductor device sealed by the cured product of this composition can withstand strict reliability tests. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic perspective view explaining the measuring method of the shear adhesive force in the Example of this invention.

It is a schematic sectional drawing explaining the package shape used for the humidification reflow test in the Example of this invention.

<Brief description of symbols for the main parts of the drawings>

1, 2: mention

3: composition (cured) layer

6: package

7: sealing material (silicone rubber composition)

8: lead frame (silver plated)

9: chip

10: wire

[(A-1) linear organopolysiloxane]

The component (A-1) has a viscosity at 25 ° C of 10 to 1,000,000 mPa · s, particularly preferably 100 to 100,000 mPa · s. The said viscosity can be measured by a rotational viscometer. This linear organopolysiloxane is represented by the following general formula (1), and has a vinyl group on the silicon atoms at both ends of the molecular chain. Moreover, the branched structure (trifunctional siloxane unit) of the quantity which does not inhibit the objective of this invention can also be contained in molecular chain.

<Formula 1>

(Wherein R ¹ is independently an unsubstituted or substituted monovalent hydrocarbon group, R ² is an unsubstituted or substituted monovalent hydrocarbon group independently of each other having no aliphatic unsaturated bond, and x and y are each 0 or a quantity) X + y is the number which makes the viscosity of 25 degreeC of this organopolysiloxane into 10-1,000,000 mPa * s, p is an integer of 1-3)

In Formula 1, R ¹ is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, specifically, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl Alkyl groups such as groups, pentyl groups, neopentyl groups, hexyl groups, cyclohexyl groups, octyl groups, nonyl groups and decyl groups; Aryl groups such as phenyl group, tolyl group, xylyl group and naphthyl group; Aralkyl groups such as benzyl, phenylethyl and phenylpropyl groups; Alkenyl groups such as vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group, hexenyl group, cyclohexenyl group and octenyl group; And some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine, bromine, chlorine, cyano groups, etc., for example, chloromethyl group, chloropropyl group, bromoethyl group, trifluoropropyl group, etc. Halogen substituted alkyl groups, cyanoethyl groups, etc. are mentioned. Preferably, R ¹ is a methyl group, a phenyl group, or a vinyl group.

In addition, as R ² , a monovalent hydrocarbon group having 1 to 10 carbon atoms, in particular 1 to 6 carbon atoms is preferable, and the same ones as those of the specific examples of R ¹ except the aliphatic unsaturated bonds such as alkenyl groups can be exemplified. . As R ^{2, a} methyl group and a phenyl group are preferable.

The following are illustrated as (A-1) component.

Wherein p is 1 or 2, q is an integer of 0 to 3, x and y are each an integer of 0 or more satisfying 0 <x + y ≦ 2,000, preferably 5 ≦ x + y ≦ 1,500, more preferably Is 10 ≦ x + y ≦ 1,000, and is an integer satisfying 0 ≦ y / (x + y) ≦ 0.5, preferably 0 ≦ y / (x + y) ≦ 0.35. As such (A-1), the following are illustrated.

x and y are as described above.

[(A-2) Organopolysiloxane of Resin Structure]

In addition, in this invention, the organopolysiloxane of resin structure can be used together with said organopolysiloxane. A resin structure (namely, three-dimensional mesh-like structure) organopolysiloxane is SiO _{2 ^{units, R 3 k R 4 p SiO}} 0 .5 units and ^{_{R 3 q R 4 r SiO 0}} .5 rise of the resin structure comprising the unit Ganopolysiloxane (wherein, in the above formula, R ³ is a vinyl group or allyl group, R ⁴ is an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bonds, k is 2 or 3, p is 0 or 1 K + p = 3, q is 0 or 1, r is 2 or 3, and q + r = 3. Moreover, as monovalent hydrocarbon group R <^4> , the C1-C10 same thing as said R <^2> , especially the thing of 1-6 are mentioned.

Here, the case where the organopolysiloxane is SiO ₂ units in the resin structure as a unit, R ³ _k R ⁴ _p SiO _0.5 units of b units, R ³ _q R ⁴ _r SiO _0.5 units c ₀ a unit, these units ratio As a molar ratio,

(b + c) /a=0.3 to 2, in particular 0.7 to 1.5

c / a = 0.1 to 2, in particular 0.2 to 1.5

It is preferable that it is preferable that this organopolysiloxane has the weight average molecular weight of polystyrene conversion by GPC of 500-10,000.

In addition, the organopolysiloxane of the resin structure, in addition to the a unit, b unit, and c unit, difunctional siloxane units and trifunctional siloxane units (that is, organosilsesquioxane units) impair the object of the present invention It may contain a small amount in the range which does not make it.

The organopolysiloxane of such a resin structure can be synthesize | combined easily by combining the compound used as each unit member so that it may become the said molar ratio, and performing co-hydrolysis, for example in presence of an acid.

Here, as said a unit member, a sodium silicate, an alkyl silicate, a polyalkyl silicate, silicon tetrachloride, etc. can be illustrated.

In addition, the following compound can be illustrated as b unit member.

In addition, the following compound can be illustrated as a c unit member.

The organopolysiloxane (A-2) of the said resin structure exhibits the effect of improving the physical strength of hardened | cured material, and the tackiness of the surface. Preferably, (A-2) component is mix | blended in the quantity of 20-70 mass% in (A) component, More preferably, it mix | blends in the quantity of 30-60 mass%. When the compounding quantity of the organopolysiloxane of resin structure is too large, the viscosity of a composition may become remarkably high or a crack may arise easily in hardened | cured material.

[(B) organohydrogenpolysiloxane]

The organohydrogenpolysiloxane (B) acts as a crosslinking agent and forms a cured product by addition reaction of the SiH group and the alkenyl group in the component (A) in the above components. Such organohydrogenpolysiloxane has 2 or more, preferably 3 or more SiH groups in 1 molecule. Especially as said organohydrogenpolysiloxane, it is represented by following General formula (2), The thing which has 2 or more, preferably 3 or more SiH groups in 1 molecule is used preferably.

H _a (R ⁵ ) _b SiO _{(4-ab) / 2}

(Wherein R ⁵ is the same or different unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond, a is 0.001 ≦ a <2, b is 0.7 ≦ b ≦ 2, and 0.8 ≦ a + b ≦ It is a number to satisfy 3)

In Formula 2, R ⁵ is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, particularly 1 to 7 carbon atoms, and for example, lower alkyl groups such as methyl groups and aryl groups such as phenyl groups, and the like. The thing illustrated by the substituent R <^2> of 1 is mentioned. A and b are preferably a number such that 0.05 ≦ a ≦ 1, 0.8 ≦ b ≦ 2, and 1 ≦ a + b ≦ 2.7. There is no restriction | limiting in particular in the position of the hydrogen atom couple | bonded with the silicon atom, The terminal of a molecule | numerator may be non-terminal.

Examples of the organohydrogenpolysiloxane include tris (dimethylhydrogensiloxy) methylsilane, tris (dimethylhydrogensiloxy) phenylsilane, 1,1,3,3-tetramethyldisiloxane, 1,3,5, 7-tetramethylcyclotetrasiloxane, both terminal trimethylsiloxy group blocking methylhydrogenpolysiloxane, both terminal trimethylsiloxy group blocking dimethylsiloxanemethylhydrogensiloxane copolymer, both terminal dimethylhydrogensiloxy group blocking dimethylpolysiloxane, both terminal dimethylhydroxy Rosenoxy group block dimethylsiloxane methyl hydrogen siloxane copolymer, both terminal trimethylsiloxy group block methyl hydrogen siloxane diphenyl siloxane copolymer, both terminal trimethyl siloxy group block methyl hydrogen siloxane diphenyl siloxane dimethyl siloxane copolymer _{, (CH 3) 2 HSiO 1} /2 copolymer containing units and SiO _{4/2 units, (CH 3) 2 HSiO 1} /2 units and SiO _4/2 units And the like (C ₆ H ₅₎ copolymer containing SiO _3/2 units.

As an example of organohydrogenpolysiloxane (B), the following linear thing is mentioned.

Wherein R ⁵ is as defined above and r is 0 or 1. c and d are each an integer of 0≤c≤500, preferably 0≤c≤200, 0≤d≤500, preferably 0≤d≤200, provided that d is 2 when r is 0 The above is an integer. (c + d) is an integer satisfying 1 ≦ c + d ≦ 1000, preferably 1 ≦ c + d ≦ 300. The following are mentioned as an example of such an organohydrogenpolysiloxane (B).

(c1 + c2 = c)

As an example of organohydrogenpolysiloxane (B), the branched compound represented by a following formula is also mentioned.

The molecular structure of the organohydrogenpolysiloxane of component (B) may be any one of linear, cyclic, branched and three-dimensional mesh structures, but the number (or degree of polymerization) of silicon atoms in one molecule is 3 to 1,000, In particular, about 3 to about 300 are used.

Such organohydrogenpolysiloxanes usually hydrolyze chlorosilanes such as R ⁵ SiHCl ₂ , (R ⁵ ) ₃ SiCl, (R ⁵ ) ₂ SiCl ₂ , (R ⁵ ) ₂ SiHCl (R ⁵ is the same as above). Or by equilibrating the siloxane obtained by hydrolysis.

The compounding quantity of this organohydrogenpolysiloxane is an amount effective in hardening | curing the said (A) component, The SiH group is 0.7-4.0 mol per mole of the total amount of an alkenyl group (for example, a vinyl group) in (A) component, Preferably Preferably it is used in the amount which becomes a molar ratio of 1.0-3.0 mol, more preferably 1.2-2.0 mol. When the said molar ratio is less than the said lower limit, it may become difficult to obtain hardened | cured material, and when it exceeds the said upper limit, unreacted SiH group may remain in a large quantity in hardened | cured material, and it may become the cause of the rubber property changing with time. have.

[(C) Metallic Condensation Reaction Catalyst]

The (C) metal-based condensation reaction catalyst reacts functional groups such as an epoxy group and an alkoxy group in the (E) adhesion-providing component described later. As the metal, aluminum and zirconium are preferable. Since the said condensation catalyst may ring-open-polymerize silicone by heat etc., a zirconia-type catalyst is more preferable by the storage and use condition of a composition. Examples of the aluminum catalyst include aluminum trihydroxide, aluminum alcoholate, aluminum acylate, salts of aluminum acylate, aluminosyloxy compound and aluminum metal chelate compound, among which aluminum chelate compound is preferable. As a catalyst containing such an aluminum chelate compound, ACS, Kerof EB-2 (all are brand names, Hof Seiyaku Co., Ltd.), etc. are mentioned, for example.

Examples of zirconium catalysts include zirconium alkoxides such as zirconium tetranormal propoxide and zirconium tetranormal butoxide, zirconium tributoxy monoacetonate, zirconium tributoxy monoacetylacetonate, and zirconium tetraacetylacetonate. Zirconium acylate, such as a zirconium tributoxy monostearate zirconium acetate, etc. are illustrated.

The compounding amount of the metal-based condensation reaction catalyst is preferably 0.005 to 10% by mass, more preferably 0.05 to 2% by mass relative to the total mass of the component (A) and the component (E). If it is less than the said lower limit, sufficient effect may not be acquired, and if it exceeds the said upper limit, it may affect the hardening characteristic (hardness, external appearance, etc.) of resin.

[(D) Platinum Group Metal-Based Addition Reaction Catalyst]

(D) A platinum group metal catalyst is mix | blended in order to produce the addition hardening reaction of the composition of this invention. Examples of the catalyst include platinum-based, palladium-based and rhodium-based ones, but platinum-based ones such as platinum, platinum black and chloroplatinic acid, for example, H ₂ PtCl ₆ · mH ₂ O, K _{2 PtCl 6, KHPtCl 6 · mH 2} O, K 2 PtCl 4, K 2 PtCl 4 · mH 2 O, PtO 2 · mH 2 O (m is a positive integer), etc. and mixtures thereof with hydrocarbons such as olefins, alcohols, or Complex with a vinyl group containing organopolysiloxane, etc. can be illustrated. These can be used individually or in combination of 2 or more types.

A compounding quantity of these catalyst components may be a so-called catalyst effective amount, and is usually used in the range of 0.1 to 1,000 ppm, preferably 0.5 to 200 ppm, in terms of platinum group metal (mass) relative to the mass of (A).

[(E) Adhesion Contributing Component]

(E) Adhesion provision component is organopolysiloxane containing 2 or more types of functional groups chosen from an alkenyl group, an alkoxy group, and an epoxy group. As an example of an alkenyl group, the vinyl group and allyl group couple | bonded with the silicon atom are mentioned. As an example of an alkoxy group, the trimethoxysilyl group couple | bonded with the silicon atom through the methoxy group, an ethoxy group, and a silethylene group is mentioned. Examples of the epoxy group include glycidoxypropyl group and 3,4-epoxycyclohexylethyl group. The organopolysiloxane contains 4 to 100 silicon atoms, preferably 4 to 50 silicon atoms, more preferably about 4 to 20 carbon atoms, and has a polystyrene reduced weight average molecular weight of 150 to 4000 linear or cyclic orls. Organosiloxane.

Examples of the (E) adhesion imparting component include those represented by the following chemical formulas.

(Wherein g, h and i are each a positive integer where g + h + i satisfies 1 to 50, preferably 4 to 20)

(Wherein L, M and N are each positive integers in which L + M + N satisfies 3 to 8, preferably 4 to 6)

0.01-10 mass parts is preferable with respect to 100 mass parts of (A) component, As for the compounding quantity of (E) adhesion provision component, More preferably, it is 0.01-5 mass parts, Most preferably, it is 0.1-3 mass parts. When the compounding quantity of (E) component is less than the said added value, adhesiveness with respect to a base material is inadequate, and when too large, it may adversely affect the hardness and surface tag property of hardened | cured material.

In the composition of the present invention, the difference between the maximum value and the minimum value among the refractive indices of each of the component (A), the mixture of the component (A) and the component (B), and the component (E) is 0.03 or less, preferably 0.02 or less, and more preferably It is characterized by being 0.015 or less. Here, "refractive index" is, may indicate a refractive index n _D for the D line of sodium in 25 ℃, and measured using an Abbe's refractometer. When the difference in refractive index is equal to or less than the above-mentioned value, not only the compatibility of these components is increased, but also the transparency of the cured product is high, which is preferable for sealing the light emitting element.

As a preferable combination of (A) component, (B) component, and (E) component which satisfy | fills the requirements of the said refractive index, the combination which (A) component, (E) component does not contain an aromatic group, (A) component, One or more of (B) component and (E) component contain an aromatic group, and the combination whose maximum value and minimum value in mol% of the aromatic group in each component satisfy | fill the following formula is mentioned. In the latter, the aromatic group is preferably a phenyl group, the mole% being the percentage of the molar amount of the aromatic group to the total molar amount of the substituents bonded to the silicon atoms.

[(Max-min) / max)] ≤0.3

[Other additives]

In addition to the above-mentioned (A)-(E) component, the composition of this invention can mix | blend the various additives known by itself as needed. For example, Reinforcing inorganic fillers, such as fumed silica and fumed titanium dioxide; And non-reinforcing inorganic fillers such as calcium carbonate, calcium silicate, titanium dioxide, ferric oxide, carbon black, and zinc oxide, in a range that does not impair the object of the present invention, preferably 1 to 50% by mass of the whole composition of the present application. It can mix | blend suitably.

Although the silicone rubber composition of this invention is manufactured by mixing each component mentioned above uniformly, normally, it divides into two liquids so that hardening does not advance, and mixes two liquids at the time of use, and hardens. Of course, a small amount of hardening inhibitors, such as acetylene alcohol, can also be added and used as 1 liquid. In addition, as a two-liquid mixing type, it is necessary to avoid copper liquid mixture of (B) component and (C) component from the danger of a dehydrogenation reaction.

Moreover, as for the viscosity in 25 degreeC measured by the rotational viscometer of the obtained silicone rubber composition, 100 to 10,000,000 mPa * s, Especially about 300-500,000 mPa * s are preferable.

The silicone rubber composition of the present invention is immediately cured by heating if necessary, and has high transparency and adheres very well to a package material such as LCP or a metal substrate, and thus covers semiconductor chips such as LEDs, photodiodes, CCDs, CMOS, and the like. Or it can be widely used as a sealing material.

In addition, the curing conditions of the composition of the present invention is not particularly limited, but can be cured at 40 to 250 ° C, preferably 60 to 200 ° C, for about 5 minutes to 10 hours, preferably about 30 minutes to 6 hours.

In order to coat | cover or seal the semiconductor chip mounted on the support body, it can heat-harden after shaping | molding to a required shape which applies the composition of this invention on this semiconductor chip.

Hereinafter, although an Example and a comparative example demonstrate this invention, this invention is not limited to the following Example. In addition, in the following example, a part represents a mass part, Me represents a methyl group, Ph represents a phenyl group, and Vi represents a vinyl group. In addition, the refractive index shows a refractive index n _D for the D line of sodium measured in the 25 ℃ using an Abbe's refractometer.

Example 1

Formula i

<Formula i>

Polysiloxane (VF) and 50 parts, SiO ₂ units of 50 mol% represented _{by, (CH 3) 3 SiO 0} .5 units 42.5 of methyl vinyl resin structure comprising in mol% and Vi ₃ SiO _{0 .5} 7.5% mole units of the siloxane (VMQ) 50 parts were mixed. The refractive index of the mixture was 1.41. Formula (ii) in an amount such that the amount of SiH groups in the mixture is 1.5 times mole per total amount of vinyl groups in the VF and VMQ components.

<Formula ii>

Organohydrogenpolysiloxane represented by was added and mixed. 0.05 part of an octyl alcohol modified solution (platinum concentration 2 mass%) of chloroplatinic acid, 0.1 part of aluminum chelate catalysts (ACS (brand name), Hof Seiyaku Co., Ltd.) to the obtained mixture (refractive index 1.41), and the following general formula

1 part of adhesion | attachment provision components (refractive index 1.42) shown by the following were mixed, and the silicone rubber composition was produced.

Example 2

The adhesion imparting component used in Example 1 is represented by the following formula

A silicone rubber composition was prepared in the same manner as in Example 1 except that the refractive index represented by was changed to 1.43.

Example 3

A mixture of 100 parts of vinylsiloxane represented by the following formula (refractive index 1.51) and 8 parts of hydrogensiloxane represented by the following formula (refractive index 1.51) was prepared.

To 100 parts of the mixture, 0.05 parts of an octyl alcohol-modified solution of platinum chloride (platinum concentration 2% by mass), 0.1 part of an aluminum chelate catalyst (ACS (trade name), manufactured by Hope Seiyaku), and an adhesion imparting component

A silicone rubber composition was prepared in the same manner as in Example 1 using 1 part of the adhesion imparting component having a refractive index of 1.50.

Example 4

Formula i

<Formula i>

A vinyl methyl siloxane (VMQ) 50 having a resin structure composed of 50 parts of polysiloxane (VF), 50 mol% of SiO ₂ units, 42.5 mol% of (CH ₃ ) ₃ SiO _0.5 units, and 7.5 mol% of Vi ₃ SiO _0.5 units. The parts were mixed. The refractive index of the mixture was 1.41. Formula (ii) in an amount such that the amount of SiH in the mixture is 1.5 times mole per total amount of vinyl groups in the VF and VMQ components.

<Formula ii>

Organohydrogenpolysiloxane represented by was added and mixed. To the obtained mixture (refractive index 1.41), 0.05 parts of an octyl alcohol modified solution (platinum concentration 2% by mass) of chloroplatinic acid, 0.1 part of zirconium alkoxide (Orgatics ZA60 (trade name), manufactured by Matsumoto Kosho), and the following chemical formula

1 part of adhesion | attachment provision components (refractive index 1.42) shown by the following were mixed, and the silicone rubber composition was produced.

Comparative Example 1

A silicone rubber composition was prepared in the same manner as in Example 1 except that the aluminum metal chelate catalyst ACS was not added.

Comparative Example 2

A silicone rubber composition was prepared in the same manner as in Example 3 except that the aluminum metal chelate catalyst ACS was not added.

Comparative Example 3

A silicone rubber composition was produced in the same manner as in Example 1 except that the adhesion imparting component used in Example 1 was changed to the adhesion imparting component used in Example 3.

[Assessment Methods]

Each composition was evaluated by the following method. The results are shown in Tables 1 to 3 below.

<Appearance, Light Transmittance, Tensile Strength, Hardness, Elongation>

The composition was heat-molded at 150 ° C./4 hours to form a cured product having a thickness of 1 mm to visually observe the appearance. In addition, the light transmittance (450 nm) was measured with the absorbance photometer. In addition, tensile strength, hardness (measured using an A-type spring tester), and elongation rate were measured in accordance with JIS K 6301.

<PPA Shear Adhesion>

As shown in FIG. 1, one end of each of the base pieces (1) and (2) of PPA (polyphthalic acid amide resin) production having a width of 25 mm was sandwiched between the composition layers 3, which were seamed at a thickness of 1 mm. The layer was sandwiched over 10 mm in length and heated at 150 ° C. for 4 hours to cure the composition layer 3. The specimen thus prepared was left at room temperature for 12 hours or more, and then tensile shear adhesion was measured by pulling both ends 4 and 5 of the specimen in the direction of the arrow in the direction of the arrow.

Coagulation Fracture Rate

With respect to the fracture surface of the test body when the shear adhesion force was measured, the cohesive failure (i.e., PPA and silicone rubber (cured product of the composition layer 3)) was not interfacially peeled with respect to the entire fracture surface. The ratio (percentage) of the area of the broken part was evaluated as the cohesive failure rate.

<Reflow Resistance>

The silicone rubber composition was enclosed in the dummy package (trade name: Submodel, Solvay) shown in FIG. 2, it hardened | cured on the conditions of 150 degreeC / 4 hours, and the humidification reflow test was performed according to MSL level 2. In FIG. 2, the semiconductor chip 9 is mounted on the silver-plated pad of the lead frame 8 in the recessed part of the package 6 which consists of PPA (polyphthalic acid amide resin), and is attached to the wire 10. In FIG. Is connected to the electrode. The silicone rubber composition 7 was injected into the recess and cured to seal the semiconductor chip 9 and the wire 10. The obtained device was placed in a 85 ° C / 85% thermostat, and the chip 9 was energized for 20 hours at a predetermined time, and the presence or absence of peeling of the composition (7) was observed. In addition, the humidification reflow test was allowed to stand for 16 hours in an atmosphere of 60 ° C./90% RH in accordance with the MSL test method, and then sufficiently absorbed. Peeling and crack generation up to 1000 hours were observed visually. These results are shown in Table 3. In addition, in Table 3, a numerical value shows the ratio (%) of the apparatus in which the defect occurrence in sample number n = 20 was recognized.

n = 20 (number of samples)

Comparative Example 3 is a composition missing the requirement of the refractive index of the present invention. The device using the composition had good thermal shock resistance but poor transparency.

Industrial availability

The composition of the invention is suitable for sealing semiconductors, in particular optical semiconductors.

Claims (8)

(A) a linear organopolysiloxane (A-1) represented by the following formula (1) and having a viscosity of 10 to 1,000,000 mPa · s at 25 ° C., or An organopolysiloxane (A-2) in the organopolysiloxane (A-1), a resin structure, SiO _{2 ^{units, R 3 k R 4 p SiO}} 0 .5 units and ^{_{R 3 q R 4 r SiO 0}} .5 Wherein, in the formula, R ³ is a vinyl or allyl group, R ⁴ is a monovalent hydrocarbon group containing no aliphatic unsaturated bonds, k is 2 or 3, p is 0 or 1, and k + p = 3, q is 0 or 1, r is 2 or 3, q + r = 3) and a combination with organopolysiloxane, <Formula 1> (Wherein R ¹ is an unsubstituted or substituted monovalent hydrocarbon group independently of each other, R ² is an unsubstituted or substituted monovalent hydrocarbon group having no aliphatic unsaturated bonds independently of each other, x and y are each 0 or a positive integer) X + y is the number which makes the viscosity of 25 degreeC of this organopolysiloxane into 10-1,000,000 mPa * s, and p is an integer of 1-3) (B) organohydrogenpolysiloxane which has 2 or more SiH groups in 1 molecule, (C) metal-based condensation reaction catalyst, (D) a platinum group metal-based addition reaction catalyst, and (E) containing an organopolysiloxane adhesion imparting component containing two or more kinds of functional groups selected from alkenyl groups, alkoxy groups and epoxy groups, Curable silicone rubber composition, wherein the difference between the maximum value and the minimum value of the refractive indexes of each of the component (A), the mixture of the component (A) and the component (B), and the component (E) is 0.03 or less. The curable silicone rubber composition according to claim 1, wherein a difference between the maximum value and the minimum value of each of the refractive indexes of the component (A), the mixture of the component (A) and the component (B), and the component (E) is 0.02 or less. The curable silicone rubber composition according to claim 1 or 2, wherein the component (A-2) is contained at 20 to 70 mass% in the component (A). Curable silicone rubber composition of Claim 1 or 2 in which both (A) component and (E) component do not contain an aromatic group. At least one of (A) component, (B) component, and (E) component contains an aromatic group, The maximum value and minimum value in mol% of the aromatic group in each component are a mathematical formula of Claim 1 or 2, A curable silicone rubber composition characterized by satisfying a formula [(maximum value-minimum value) / maximum value)]? The component (B) is used in an amount such that the SiH group in the component (B) is 0.7 to 4.0 mol per mol of the alkenyl group in the component (A), and the component (E) is 100 mass of the component (A). 0.01 to 10 parts by mass with respect to the part, (C) component to 0.005 to 10 mass% with respect to 100 parts by mass in total of the component (A) and (E), and (D) component to the mass of the component (A). Curable silicone rubber composition, containing 0.1 to 1,000 ppm in terms of platinum group metal. The curable silicone rubber composition according to claim 1 or 2, wherein the component (C) is an aluminum catalyst or a zirconium catalyst. The semiconductor device which has a semiconductor chip and the hardened | cured material of the curable silicone rubber composition of Claim 1 or 2 which coat | covers or seals the said chip | tip.