JP5278384B2 - Die-bonding agent composition for optical semiconductor element and optical semiconductor device using the composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide die bond agent composition for an optical semiconductor element capable of providing a cured material excellent in heat resistance, UV resistance, and adhesiveness. <P>SOLUTION: The die bond agent composition for an optical semiconductor element contains the following components: (A) a silicone resin having a unit expressed by general formula (1): [R<SP>1</SP>R<SP>2</SP><SB>x</SB>SiO<SB>(3-x)/2</SB>] at a molar fraction of 0.25 to 0.75, a unit expressed by general formula (3): [(R<SP>3</SP><SB>2</SB>SiO)<SB>n</SB>] at a molar fraction of 0.25 to 0.75, and an epoxy equivalent value of 200 to 1,300 g/eq, wherein R<SP>1</SP>is a group expressed by formula (2), R<SP>4</SP>is a divalent group, R<SP>2</SP>is a hydroxyl group, a monovalent hydrocarbon group, or an alkoxy group, x is an integer of 0, 1 or 2, R<SP>3</SP>is a monovalent hydrocarbon group, and n is an integer of 3 to 15; (B) an epoxy resin including the group of formula (2); (C) a curing agent; (D) a curing catalyst; (E) an inorganic filler; (F) a silane coupling agent; and (G) an antioxidant agent. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a die-bonding agent composition for bonding an optical semiconductor element to a substrate or the like, and more specifically, a silicone resin having an alicyclic epoxy group and a linear organopolysiloxane structure having a predetermined length, and an alicyclic type The present invention relates to a die bond agent composition containing an epoxy resin and giving a cured product excellent in heat resistance, UV resistance and adhesiveness, and an optical semiconductor device using the same.

  As the die bond agent composition for optical semiconductor elements, a bisphenol A type epoxy resin excellent in adhesiveness and mechanical strength, an epoxy resin having no UV absorption, for example, a hydrogenated bisphenol A type epoxy resin or an alicyclic epoxy resin, A composition containing a curing agent and a curing catalyst is frequently used. However, as the luminance and output of the LED element increase, there are problems of discoloration and cracking of the adhesive layer due to light, heat, etc. from the LED element.

  As a solution to these problems, a resin in which an epoxy group is introduced into a silicone resin that does not absorb UV and gives a flexible cured product is known. For example, a cyclic ether such as a glycidyl group or an epoxycyclohexyl group. There is a silicone resin (Patent Document 1) having one or more containing groups. Moreover, although it is a sealant use, the reaction product (patent document 2) of an epoxy alkoxysilane and silanol, and the thing using together an alicyclic epoxy modified silicone resin and an alicyclic epoxy resin (patent document 3) It has been known. However, none of these is satisfactory as a die-bonding agent in terms of heat resistance and adhesiveness.

JP 2008-45088 A Japanese Patent Laid-Open No. 7-97433 JP 2006-282898 A

This invention is made | formed in view of the said situation, and it aims at providing the die-bonding agent composition for optical semiconductor elements which gives the hardened | cured material excellent in heat resistance, UV resistance, and adhesiveness.

  The present inventors have found that the above-described problems can be achieved by using a cycloaliphatic epoxy resin in combination with a silicone resin having an alicyclic epoxy group and a linear organopolysiloxane structure having a predetermined length.

That is, the present invention
The die-bonding agent composition for optical semiconductor elements containing the following (A)-(G) component is provided.
(A) The structural unit represented by the general formula (1) is included at a molar fraction of 0.25 to 0.75, and the structural unit represented by the general formula (3) is included at a molar fraction of 0.25 to 0.00. 100 parts by mass of a silicone resin having an epoxy equivalent of 200 to 1300 g / eq,

General formula (1):
[R ¹ R ² _x SiO _{(3-x) / 2} ] (1)
[In Formula (1),
R ¹ represents the following formula (2):

(In Formula (2), R ⁴ is a C _1-20 divalent group)
A group represented by
R ² is a hydroxyl group, a C _1-20 monovalent hydrocarbon group, or a C _1-6 alkoxy group, and when there are a plurality of R ^{2 in the} silicone resin, they are the same or different,
x is an integer of 0, 1 or 2, and when there are a plurality of x in the silicone resin, they are the same or different. ],

General formula (3):
[(R ³ ₂ SiO) _n ] (3)
(Wherein R ³ is a C _1-20 monovalent hydrocarbon group and n is an integer of 3 to 15)

(B) Epoxy resin having a group represented by the above formula (2) 10 to 100 parts by mass (C) Curing agent having a functional group reactive with an epoxy group (A) Component and epoxy in component (B) The amount by which the functional group reactive with the epoxy group becomes 0.3 to 1.0 mol with respect to 1 mol of the total of the groups (D) curing catalyst (A) component and (B) component in total 100 mass 0.01 to 3 parts by mass with respect to parts (E) Inorganic filler (A) to (D) 3 to 30 parts by mass (F) silane coupling agent with respect to 100 parts by mass in total of components 0.1 to 0. 5 mass parts (G) antioxidant 0.1-0.5 mass parts.

  The present invention also provides an optical semiconductor device to which the above-mentioned die bond agent composition is applied. More specifically, an optical semiconductor device comprising a substrate and an optical semiconductor element bonded on the substrate by a cured product layer of the die bond agent composition is provided.

  The composition of the present invention is excellent in heat resistance, UV resistance and adhesiveness, and can form a cured product suitable as a die bond agent.

The measurement result by ²⁹ Si-NMR of the organopolysiloxane obtained in Synthesis Example 1 is shown.

<(A) Silicone resin>
(A) The silicone resin has the formula (1):
[R ¹ R ² _x SiO _{(3-x) / 2} ] (1)
(In the formula (1), R ¹ is the following formula (2):

(In Formula (2), R ⁴ is a C _1-20 divalent group)
A group represented by
R ² is a group independently selected from a hydroxyl group, a C _1-20 monovalent hydrocarbon group, and a C _1-6 alkoxy group,
x is an integer of 0, 1 or 2. ]
At least one structural unit (hereinafter also referred to as “unit a”) having a molar fraction of 0.25 to 0.75, and formula (3):
[(R ³ ₂ SiO) _n ] (3)
(In the formula, R ³ are each independently a C _1-20 monovalent hydrocarbon group, and n is an integer of 3 to 15).
The structural unit represented by (hereinafter also referred to as “unit b”) at a molar fraction of 0.25 to 0.75,
It is a silicone resin having an epoxy equivalent of 200 to 1300 g / eq.

In addition to the unit a and the unit b, the silicone resin as the component (A) may contain other siloxane units (hereinafter also referred to as “unit c”) as structural units. As the unit c, for example, the formula (4):
[R ⁵ R ² _y SiO _{(3-y) / 2} ] (4)
(In the formula (4), R ⁵ is, for example, an aryl group such as a phenyl group, a toluyl group or a naphthyl group, a cycloalkyl group such as a cyclopentyl group or a cyclohexyl group, preferably a phenyl group,
R ² is as described above,
y is an integer of 0, 1 or 2, and when there are a plurality of units c in the silicone resin, these units c are the same or different. ]
As unit c, when R ⁵ is a phenyl group, it is advantageous in terms of improving resin strength and adhesive strength.

  The molar fraction in the silicone resin of the component (A) of the unit c is 0 to 0.3, preferably 0 to 0.2.

  The silicone resin as component (A) can be represented by the following average composition formula (5) as a preferred example.

(In the formula (5), R ¹ , R ² , R ³ , x and n are as described above,
R ⁵ is an aryl group or a cycloalkyl group,
y is independently an integer of 0, 1 or 2;
a is a number from 0.25 to 0.75,
b is a number from 0.25 to 0.75,
c is a number from 0 to 0.3, where a + b + c = 1. )

In Formula (3) and Formula (5), n is an integer of 3 to 15, preferably 3 to 10. When n is less than the lower limit, heat resistance is poor. On the other hand, when n exceeds the upper limit, the hardness and adhesive strength of the cured product are lowered. x is an integer of 0, 1 or 2 independently of each other. In the silicone resin, a unit in which x is 0 (T unit), a unit in which x is 1 (D unit), and a unit in which x is 2 (M unit) are both present in one molecule. The proportion of these units depends on the type of R ^{2 in} the monomer (epoxy group-containing silane) used in the production method described later and the degree of progress of hydrolysis / condensation. The abundance ratio of T unit, D unit and M unit is preferably a molar ratio of T unit: (total of D unit and M unit) of 1: 99-60: 40, more preferably 2: 98-58: 42. More preferably, it is 4:96 to 56:44, and still more preferably 5:95 to 50:50. Furthermore, the molar ratio of T unit: D unit: M unit is preferably 1:84:15 to 60: 39: 1, more preferably 2:82:16 to 58: 41: 1, and even more preferably. Is from 4:78:18 to 56: 42: 2, and more preferably from 5:75:20 to 50: 48: 2. When there are too many ratios of T unit, there exists a tendency for the light resistance of hardened | cured material to worsen.

In the (R ³ ₂ SiO) _n unit represented by the formula (3), for example, the unit in which n is 3 has the following structure.

The (R ³ ₂ SiO) _n unit may be in the main chain when the silicone resin is linear, or may be in any branched chain as long as it is branched. By containing the (R ³ ₂ SiO) _n unit, a cured product having excellent thermal shock resistance can be obtained.

In the formula (1), R ¹ is a monovalent group including an epoxycyclohexyl group represented by the following formula (2).

In the formula (2), R ⁴ is a C _1-20 divalent group such as an alkylene group such as methylene, ethylene or propylene, or an oxyalkylene group such as oxymethylene, oxyethylene or oxypropylene (that is, —OR—). Where R is an alkylene group which binds to the cyclohexane ring in formula (2), a carbonyl group, and an oxycarbonyl group (ie —OC (═O) —, in formula (2), the carbonyl group side binds to the cyclohexane ring. ) Is included. R ⁴ is preferably an alkylene group, more preferably an ethylene group. Examples of the group having an ethylene group include a β- (3,4-epoxycyclohexyl) ethyl group.

In the silicone resin as the component (A), 2 to 50, preferably 5 to 30, R ¹ are present per molecule. When the number of the groups is less than the lower limit, the hardness of the cured product obtained by curing the composition is low, and when the number exceeds the upper limit, the strength of the cured product is low and cracks are likely to occur.

R ² is a group selected from a hydroxyl group, a C _1-20 monovalent hydrocarbon group, and a C _1-6 alkoxy group. Examples of the hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group and butyl group, cycloalkyl groups such as cyclopentyl group and cyclohexyl group, aryl groups such as phenyl group, alkaryl groups such as tolyl group, norbonenyl. Examples thereof include a crosslinked cyclic group such as a group. _{Examples of the} C _1-6 alkoxy group include a methoxy group and an ethoxy group. Preferably, R ² is a methyl group or a phenyl group.

R ³ is, independently of each other, a C _1-20 monovalent hydrocarbon group, and the groups described above with respect to R ² are exemplified.

a is a number of 0.25 to 0.75, preferably a number of 0.4 to 0.7. If a is less than the lower limit value, the amount of epoxy groups is small, so the degree of cure of the composition is low, and if it exceeds the upper limit value, the amount of epoxy groups is large, and the synthesized resin gels, which is not preferable. b is a number of 0.25 to 0.75, preferably a number of 0.3 to 0.6. c is a number from 0 to 0.3, preferably a number from 0 to 0.2. When c exceeds the upper limit, the light resistance of the cured product tends to deteriorate. Formula (5) is a composition formula showing the average abundance of each structural unit, and a + b + c = 1.

The component (A) is a linear organopolysiloxane represented by the following formula (6):

(In the above formula, R ³ is as described above, X is a hydrolyzable group such as an alkoxy group and a halogen atom, and m is an integer of 1 to 13.)
Following formula (7):

(In the above formula, R ¹ and R ² are as described above, but at least one of R ² is a hydroxyl group or a C _1-6 alkoxy group.)
The epoxy group-containing silane represented by the formula (8), which is a monomer for forming an optional unit c, if necessary:

(In the above formula, R ² and R ⁵ are as described above, but at least one of R ² is a hydroxyl group or a C _1-6 alkoxy group.)
It can obtain by carrying out a hydrolysis and a condensation reaction according to a usual method with the silane represented by these.

  The resulting silicone resin of component (A) has a polystyrene-equivalent weight average molecular weight of 1,000 to 30,000, preferably 2,000 to 20,000. The epoxy equivalent is 200 to 1300 g / eq, preferably 300 to 1100 g / eq. When the epoxy equivalent is less than the lower limit, the cured product becomes too hard and cracks are likely to occur. On the other hand, when the epoxy equivalent exceeds the upper limit, the adhesiveness of the cured product is deteriorated.

<(B) Epoxy resin>
The composition of this invention contains the epoxy resin which has group represented by the said Formula (2). Preferably, two groups represented by the above formula (2) are included, provided that R ⁴ may be different from each other. As shown in the examples below, the epoxy resin is more heat resistant than the hydrogenated epoxy resin while exhibiting almost the same adhesion as the case of using a hydrogenated epoxy resin having a cyclohexane ring in the same manner as the epoxy resin. Gives a cured product excellent in heat resistance and UV resistance. Most preferably, 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate represented by the following formula (9) is used.

  The resin is commercially available from Daicel Chemical Industries, Ltd. under the trade name “Celoxide 2021P”.

  (B) The compounding quantity of the epoxy resin of a component is 10-100 mass parts with respect to 100 mass parts of (A) component, Preferably it is 20-80 mass parts. When the blending amount is less than the lower limit value, sufficient adhesive strength cannot be obtained. On the other hand, when the blending amount exceeds the upper limit value, heat resistance and UV resistance are lowered.

<(C) Curing agent>
As the curing agent, a curing agent having a functional group reactive with an epoxy group is used. For example, amine-based curing agents, phenol-based curing agents, and acid anhydride-based curing agents are exemplified, and acid anhydride-based curing agents are preferred. Examples of the acid anhydride curing agent include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride, Mixture of 3-methyl-hexahydrophthalic anhydride and 4-methyl-hexahydrophthalic anhydride, tetrahydrophthalic anhydride, nadic anhydride, methyl nadic anhydride, norbornane-2,3-dicarboxylic anhydride, methylnorbornane-2 2,3-dicarboxylic anhydride, 2,4-diethylglutaric anhydride, etc., among which hexahydrophthalic anhydride and its derivatives are preferred.

  The compounding amount of the curing agent of component (C) is a functional group having reactivity with an epoxy group (of acid anhydride curing agent) with respect to a total of 1 mol of the epoxy groups in component (A) and component (B). In such a case, the amount of the acid anhydride group represented by -CO-O-CO- is 0.3 to 1.0 mol, preferably 0.4 to 0.8 mol. Here, the “functional group having reactivity with an epoxy group” means an amino group possessed by an amine curing agent, a phenolic hydroxyl group possessed by a phenol curing agent, and an acid anhydride group possessed by an acid anhydride curing agent. .

<(D) Curing catalyst>
Examples of the curing catalyst include quaternary phosphonium salts such as tetrabutylphosphonium · O, O-diethyl phosphorodithioate and tetraphenylphosphonium tetraphenylborate, and organic phosphine-based curing catalysts such as triphenylphosphine and diphenylphosphine. , 8-diazabicyclo (5,4,0) undecene-7, tertiary amine-based curing catalyst such as triethanolamine, benzyldimethylamine, 1,8-diazabicyclo (5,4,0) undecene-7 phenol salt, 1 , 8-diazabicyclo (5,4,0) undecene-7 octylate, 1,8-diazabicyclo (5,4,0) undecene-7 p-toluenesulfonate, 1,8-diazabicyclo (5,4, 0) Undecene-7 quaternary ammonium salts such as formate, zinc octylate, naphtha Organic carboxylates such as zinc phosphate, aluminum chelate compounds such as aluminum bisethyl acetoacetate / monoacetylacetonate, aluminum ethyl acetoacetate / diisopropylate, 2-methylimidazole, 2-phenyl-4-methylimidazole, etc. Examples thereof include imidazoles, and preferred are quaternary phosphonium salts and quaternary ammonium salts.

  (D) The compounding quantity of a curing catalyst is 0.01-3 mass parts with respect to a total of 100 mass parts of (A) component and (B) component, Preferably it is 0.05-1.5 mass parts. If the amount of the curing catalyst is less than the lower limit, the effect of promoting the reaction between the epoxy resin and the curing agent may not be sufficient. On the contrary, if the amount of the curing catalyst is larger than the upper limit value, it may cause discoloration during curing or reflow test.

<(E) Inorganic filler>
Inorganic fillers include silica, alumina, zirconia, aluminum hydroxide, titanium oxide, bengara, calcium carbonate, magnesium carbonate, aluminum nitride, magnesium oxide, zirconium oxide, boron nitride, silicon nitride, silicon carbide, and mixtures thereof. Silica is preferably used in terms of particle size, purity and the like.

  The silica may be wet silica, dry silica and a mixture thereof. For example, precipitated silica, silica xerogel, fumed silica, fused silica, crystalline silica, and a mixture thereof may be mentioned, and these surfaces may be hydrophobized with an organic silyl group. As these commercial products, for example, Aerosil (manufactured by Nippon Aerosil Co., Ltd.), Nipsil (manufactured by Nippon Silica Co., Ltd.), Cabosil (manufactured by Cabot Corporation of the United States), Santo Cell (manufactured by Monsanto Corporation of the United States), etc. Can be mentioned.

BET specific surface area of the inorganic filler (BET specific surface area) ^is preferably 50m ² / g~400m 2 / g, more preferably ^{150m 2 / g~380m 2 / g,} 180~350m Particularly preferred is ² / g. Within such a range, good thixotropy of the composition can be obtained.

  (E) The compounding quantity of a component is 3-30 mass parts with respect to a total of 100 mass parts of the said (A)-(D) component, More preferably, it is 3-27 mass parts, Most preferably, it is 5-25 mass parts. It is. Beyond such a range, the handleability of the composition becomes poor, and it is difficult to obtain thixotropy suitable for shape retention after transfer by dispensing or stamping.

<(F) Silane coupling agent>
Examples of the silane coupling agent include epoxy silane, vinyl silane, methacryloxy silane, amino silane, mercapto silane compound and the like. Among these, mercapto silane coupling agent is preferable. (F) The compounding quantity of a component is 0.1-0.5 mass part with respect to 100 mass parts of (A) component, Preferably it is 0.2-0.3 mass part.

<(G) Antioxidant>
Antioxidants include phosphorous acid compounds and hindered phenol antioxidants, with hindered phenol antioxidants being preferred. Moreover, as an ultraviolet absorber, a hindered amine type ultraviolet absorber is preferable. The compounding quantity of (G) component is 0.1-0.5 mass part with respect to 100 mass parts of (A) component, Preferably it is 0.1-0.3 mass part.

<Other ingredients>
In addition to the above components, conventional additives such as ultraviolet absorbers, anti-degradation agents, phosphors, thermoplasticizers, diluents, etc. may be used in combination in amounts that do not impair the purpose of the present invention. It doesn't matter.

  The composition of this invention can be manufactured by mix | blending each said component and various additives as needed, and melt | dissolving or melt-mixing. Melt mixing may be a known method. For example, the above components may be charged into a reactor and melt-mixed in a batch manner, or each of the above components may be charged into a kneader such as a kneader or a heat triple roll. And can be continuously melt-mixed. (D) The curing catalyst is preferably preliminarily heated and dissolved and mixed with (B) the curing agent, and dispersed and mixed with an epoxy resin or the like at the final stage of mixing.

  When the optical semiconductor element is bonded to a substrate or the like with the obtained die bond agent composition, it can be applied using a known method such as stamping. The applied composition may be heated in advance at a predetermined temperature, and water, organic acid, alcohol or the like may be added as necessary to increase the viscosity (or B-stage).

  Although it is preferable to set suitably the hardening conditions of a die-bonding agent according to an apparatus, Usually, it heats at 100 degreeC for about 1 to 2 hours, and also heats at 150-200 degreeC for 0.1 to 2 hours.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not restrict | limited to these Examples. "Part" in the following means a part by mass, Me represents a methyl group, and Ph represents a phenyl group.

-Synthesis of component (A)-
In the following synthesis examples, the average value of n in the average composition formula showing the product is the sum of the products of each n and the peak area at each n in the molecular weight distribution chart by GPC measurement. The value obtained by dividing. For example, when n of a product is an integer of 2 to 20, [2 × (peak area of n = 2) + 3 × (peak area of n = 3) +... + 20 × (peak area of n = 20)] / [(Peak area of n = 2) + (peak area of n = 3) +... + (Peak area of n = 20)]].

[Synthesis Example 1]
In the reactor, MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer of 1 to 8, average is 1.5) 306 g (1.00 mol), β- (3, 4-Epoxycyclohexyl) ethyltrimethoxysilane (KBM303 manufactured by Shin-Etsu Chemical Co., Ltd.) 246 g (1.00 mol) and isopropyl alcohol 500 ml were charged, and then 12 g of a 25 mass% tetramethylammonium hydroxide aqueous solution and 110 g of water were added. Stir at room temperature for 3 hours. Next, 500 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The organic layer (toluene solution) separated using a separatory funnel was washed with hot water, and then toluene was distilled off under reduced pressure. As a result, the target organopolysiloxane having a structure represented by the following average composition formula (“ Resin 1 ”) was obtained.
-The polystyrene equivalent weight average molecular weight measured by GPC of Resin 1 was 4300, and the epoxy equivalent (measured by titration method (JIS K7236), the same applies hereinafter) was 403 g / eq.

-The measurement result by ²⁹ Si-NMR is shown in FIG. The peak near −55 to −70 ppm reflects Si atoms forming T units, and the peak near −10 to −25 ppm reflects Si atoms forming D units and M units. From this result, it was found that the first structural unit (left unit) constituting the average composition formula contained about 22 mol% of T units and about 78 mol% of D units and M units in total. .

(However, n is an integer of 3 to 10, an average of 3.5, and x is 0, 1, 2, or a combination of two or more thereof.)

[Synthesis Example 2]
In a reactor, MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer of 1 to 8, average is 1.5) 275 g (0.90 mol), phenyltrimethoxysilane (KBM103 manufactured by Shin-Etsu Chemical Co., Ltd.) 59.5 g (0.30 mol), β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (KBM303 manufactured by Shin-Etsu Chemical Co., Ltd.) 221.8 g (0.90 mol), After charging 500 ml of isopropyl alcohol, 12 g of a 25 mass% aqueous solution of tetramethylammonium hydroxide and 110 g of water were added and stirred at room temperature for 3 hours. Next, 500 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The toluene solution was washed with hot water using a separatory funnel. Toluene was distilled off under reduced pressure to obtain the desired organopolysiloxane (referred to as “resin 2”) represented by the following average composition formula. The polystyrene equivalent weight average molecular weight measured by GPC of Resin 2 was 6200, and the epoxy equivalent was 354 g / eq.

From the measurement results by ²⁹ Si-NMR, the first structural unit (the left unit) constituting the average composition formula was about 36 mol%, the D unit and the M unit in the same manner as in Synthesis Example 1. It was found that the total structural unit was about 58 mol% and the third structural unit (right unit) constituting the average composition formula contained about 6 mol% of the T unit phenyl group.

(However, n is an integer of 3 to 10 and is an average of 3.5, x and y are independently 0, 1 or 2, and x is 0, 1 or 2 in the first structural unit. Are present together, and in the third structural unit, y is 0, 1 or 2 together.)

[Synthesis Example 3]
In the reactor, MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer of 1 to 13, average is 8) 787 g (1.00 mol), β- (3,4 -Epoxycyclohexyl) Ethyltrimethoxysilane (KBM303 manufactured by Shin-Etsu Chemical Co., Ltd.) 246g (1.00 mol) and isopropyl alcohol 1000ml were charged, and then 12g of a 25% by weight aqueous solution of tetramethylammonium hydroxide and 110g of water were added. Stir at room temperature for 3 hours. Next, 1000 ml of toluene was put into the system and neutralized with an aqueous solution of sodium dihydrogen phosphate. The toluene solution was washed with hot water using a separatory funnel, and then toluene was distilled off under reduced pressure to obtain the desired organopolysiloxane (referred to as “resin 3”) represented by the following average composition formula. . The polystyrene equivalent weight average molecular weight measured by GPC of Resin 3 was 5600, and the epoxy equivalent was 750 g / eq.

From the measurement results by ²⁹ Si-NMR, the same as in Synthesis Example 1, the first structural unit (left unit) constituting the average composition formula is about 10 mol% T unit, D unit and M It was found to contain about 90 mol% in total.

(However, n is an integer of 3 to 15 and is 10 on average, and in the first structural unit, x is 0, 1 or 2 together.)

-Synthesis of silicone resin used in comparative examples-
[Synthesis Example 4]
In the reactor, MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer of 1 to 8, average is 1.5) 306 g (1.00 mol), 3-glycid After charging 236 g (1.00 mol) of xylpropyltrimethoxysilane (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.) and 500 ml of isopropyl alcohol, 12 g of a 25 mass% aqueous solution of tetramethylammonium hydroxide and 110 g of water were added at room temperature. Stir for hours. Next, 500 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The toluene solution was washed with hot water using a separatory funnel, and then toluene was distilled off under reduced pressure to obtain the desired organopolysiloxane (referred to as “resin 4”) represented by the following average composition formula. .

-The polystyrene equivalent weight average molecular weight measured by GPC of the resin 4 was 4300, and the epoxy equivalent was 416 g / eq.
From the measurement results by ²⁹ Si-NMR, the first structural unit (left unit) constituting the average composition formula was about 23 mol%, D unit and M in the same manner as in Synthesis Example 1 It was found to contain about 77 mol% in total.

(However, n is an integer of 3 to 10, an average of 3.5, and in the first structural unit, x is 0, 1 or 2 together.)

[Synthesis Example 5]
To the reactor, MeO (Me) ₂ SiO (Me ₂ SiO) _m Si (Me) ₂ OMe (m is an integer of 1 to 28, average is 18), 765 g (0.50 mol), β- (3,4 -Epoxycyclohexyl) Ethyltrimethoxysilane (KBM303 manufactured by Shin-Etsu Chemical Co., Ltd.) 123 g (0.50 mol) and 800 ml of isopropyl alcohol were charged, and 6.0 g of a 25 mass% aqueous solution of tetramethylammonium hydroxide and 55 g of water were added. The mixture was added and stirred at room temperature for 3 hours. Next, 800 ml of toluene was put into the system and neutralized with an aqueous sodium dihydrogen phosphate solution. The toluene solution was washed with hot water using a separatory funnel, and then toluene was distilled off under reduced pressure to obtain the desired organopolysiloxane (referred to as “resin 5”) represented by the following formula. The weight average molecular weight in terms of polystyrene measured by GPC of Resin 5 was 3500, and the epoxy equivalent was 1300 g / eq.

From the measurement results by ²⁹ Si-NMR, the first structural unit (left unit) constituting the average composition formula was about 5 mol% T unit, D unit and M unit as in Synthesis Example 1. It was found to contain about 95 mol% in total.

(However, n is an integer of 3 to 30, an average of 20, and in the first structural unit, x is 0, 1 or 2 together.)

-Preparation of composition-
After mixing each component sufficiently with a stirrer / mixer in the formulations (parts by mass) shown in Tables 1 and 2 below, a die-bonding agent composition was prepared through a three-roll mill. Each component in these tables is as follows. In the table, a blank column means “0”.
(B) Epoxy resin: 3,4-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (Daicel Chemical Industries, Celoxide 2021P)
(C) Curing agent: 4-methylhexahydrophthalic anhydride (manufactured by Shin Nippon Rika Co., Ltd., Ricacid MH)
(D) Curing catalyst: quaternary phosphonium salt (manufactured by San Apro Co., Ltd., U-CAT5003)
(E) Inorganic filler: fumed silica (manufactured by Shin-Etsu Chemical Co., Ltd., BET specific surface area 300 m ² / g)
(F) Silane coupling agent: 3-mercaptopropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-803)
(G) Antioxidant: Pentaerythritol tetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] (manufactured by ADEKA Corporation, ADK STAB AO-60)

-Epoxy resin used in comparative examples-Hydrogenated bisphenol A type epoxy resin (Japan Epoxy Resin Co., Ltd., YX8000)
..Bisphenol A type epoxy resin (Japan Epoxy Resin Co., Ltd., jER828)

-Characterization of composition and cured product-
The characteristics evaluation of the obtained composition and hardened | cured material was performed with the following method. Curing was performed by heating the composition at 100 ° C. for 1 hour and then at 150 ° C. for 2 hours. The results are shown in Tables 1 and 2.
(1) Viscosity Viscosity was measured at 23 ° C with an E-type rotational viscometer manufactured by Toki Sangyo.
(2) Thixo ratio The thixo ratio was determined from the viscosity ratio at 5 rpm and 50 rpm measured with the E-type rotational viscometer.
(4) Hardness It measured about the rod-shaped hardened | cured material based on JISK6301 (type D).
(5) UV resistance The light transmittance (T ₀ ) at a wavelength of 450 nm of the sheet-like cured product having a thickness of 1 mm was measured with a spectrophotometer U-4100 (manufactured by Hitachi High-Tech). The cured product, a UV irradiation apparatus equipped with a 365nm bandpass filter (illuminance 100 mW / cm ^2), measured in the same manner the light transmittance after the irradiation for 24 hours _{(T 1), T 1 /} T 0 (% )
(6) Heat resistance The light transmittance (T ₀ ) at a wavelength of 450 nm of a 1 mm thick sheet-like cured product was measured with a spectrophotometer U-4100 (manufactured by Hitachi High-Tech). The cured product was measured for light transmittance (T ₁ ) after heating at 150 ° C. for 400 hours in the same manner, and T ₁ / T ₀ (%) was determined.
(7) Adhesive strength About 0.1 mg of the composition was applied to an Ag-plated substrate (42 alloy), and a 2 mm × 2 mm square Si chip was placed on it and cured under the above curing conditions to prepare a test piece. The shear bond strength was determined by a shearing method using a 4000 bond tester manufactured by the company. Five test pieces were measured for each composition, and an average value was obtained.

-Creation and evaluation of LED devices-
An LED premold package (3 mm square, thickness 1 mm, recess inner diameter 2.6 mm) having a circular recess for mounting the optical semiconductor element and having a silver plated bottom was prepared. The composition was transferred onto the bottom of the package by stamping to coat the bottom, and an InGaN-based blue light-emitting element was bonded to the resulting coating using a die bonding apparatus. Thereafter, the composition film was cured by heating at 180 ° C. for 1.5 hours. Next, the light emitting element was connected to an external electrode with a gold wire. Thereafter, a silicone hybrid resin composition (LPS-7410, manufactured by Shin-Etsu Chemical Co., Ltd.) was filled in the recess, and cured at 100 ° C. for 1 hour and further at 150 ° C. for 4 hours to seal the device. In this manner, ten sealed LED devices were prepared for each composition. These were then subjected to testing.

・ Temperature cycle test:
The five sealed LED devices obtained were then subjected to a temperature cycle under the conditions without turning on the LEDs.

..Temperature cycle conditions:
One cycle: 20 minutes at -40 ° C, then 20 minutes at 125 ° C.

    Repeat cycle number: 1000 cycles and 2000 cycles

・ High temperature and high humidity lighting test:
Under constant temperature and humidity conditions of 65 ° C. and 95% RH, it was left for 500 hours in a state where it was turned on by energizing 50 mA.

  After leaving, the adhesion failure such as peeling between the LED element and the bottom of the recess, the presence or absence of cracks in the adhesive layer, and the presence or absence of discoloration of the adhesive layer around the chip were observed. The results are shown in Tables 1 and 2.

  The composition of Comparative Example 1 exceeds the range of the ratio of the component (B) of the present invention, is inferior in UV resistance and heat resistance, and inferior in impact resistance. The compositions of Comparative Examples 2 and 3 contain a hydrogenated epoxy resin or an aromatic epoxy resin instead of the component (B) of the present invention. All of these are inferior in UV resistance and heat resistance. The composition of Comparative Example 4 lacks the component (B) of the present invention, has low adhesive strength and hardness, and low resin strength. The composition of Comparative Example (5) uses a silicone resin in which the epoxy group is not an epoxycyclohexane ring but a glycidyl group instead of the component (A) of the present invention, but the adhesive strength, UV resistance, Inferior in heat resistance and impact resistance. In Comparative Example 6, the chain length of the linear organopolysiloxane of the component (A) of the present invention exceeds the range of the present invention, and is inferior in adhesive strength and impact resistance. On the other hand, the composition of an Example is excellent in the balance of adhesive strength, heat resistance, UV resistance, and hardness.

  The composition of the present invention gives a cured product excellent in heat resistance, UV resistance and adhesiveness, and can form a highly reliable adhesive part. The composition is suitable as a die bond agent for an optical semiconductor element.

Claims (10)

The die-bonding agent composition for optical semiconductor elements containing the following (A)-(G) component.
(A) The following average composition formula (5):

(Wherein R ¹ is the following formula (2):

(Wherein R ⁴ is a C _1-20 alkylene group )
A group represented by
R ² is a methoxy group or a phenyl group, and when there are a plurality of R ^{2 in the} silicone resin, they are the same or different, R ³ is a C _1-20 alkyl group, and R ⁵ is a phenyl group. x is an integer of 0, 1 or 2, and when there are a plurality of x in the silicone resin, they are the same or different. n is an integer of 3-15.
y is independently an integer of 0, 1 or 2;
a is a number from 0.25 to 0.75,
b is a number from 0.25 to 0.75,
c is a number from 0 to 0.3, where a + b + c = 1. )
100 parts by mass of a silicone resin represented by formula (E) and having an epoxy equivalent of 200 to 1300 g / eq,
(B) Epoxy resin having a group represented by the above formula (2) 10 to 100 parts by mass (C) Curing agent having a functional group reactive with an epoxy group (A) Component and epoxy in component (B) The amount by which the functional group reactive with the epoxy group becomes 0.3 to 1.0 mol with respect to 1 mol of the total of the groups (D) curing catalyst (A) component and (B) component in total 100 mass 0.01 to 3 parts by mass with respect to parts (E) Inorganic filler (A) to (D) 3 to 30 parts by mass (F) silane coupling agent with respect to 100 parts by mass in total of components 0.1 to 0. 5 mass parts (G) antioxidant 0.1-0.5 mass parts. The die-bonding agent composition according to claim 1 , wherein the component (B) is an epoxy resin represented by the following formula (9).

The die-bonding agent composition according to claim 1 or 2 , wherein the epoxy equivalent of component (A) is 300 to 1100 g / eq. The die-bonding agent according to any one of claims 1 to 3 , wherein R ¹ is a β- (3,4-epoxycyclohexyl) ethyl group, R ² is a methoxy group , and R ³ is a methyl group. Composition. (C) A component is an acid anhydride hardening | curing agent, The die-bonding agent composition which concerns on any one of Claims 1-4 . (D) The die-bonding agent composition according to any one of claims 1 to 5 , wherein the curing catalyst is a quaternary phosphonium salt compound. (E) BET specific surface area of the component is 180m ² / g~350m ² / g, a die bonding agent composition according to any one of claims 1-6. The die-bonding agent composition according to any one of claims 1 to 7 , wherein the component (F) is a mercapto-based silane coupling agent. The die-bonding agent composition according to any one of claims 1 to 8 , wherein the component (G) is a hindered phenol antioxidant. An optical semiconductor device to which the die bond agent composition according to any one of claims 1 to 9 is applied.

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