JP2012172012A - Thermosetting epoxy resin composition and optical semiconductor device - Google Patents

Abstract

A thermosetting epoxy resin composition that retains reflectivity, heat resistance and light resistance for a long period of time and gives a cured product having excellent mechanical strength, a reflecting member made of a cured product of the composition, and the An optical semiconductor device having a reflecting member is provided.
A combination of (A) (A-1) a triazine derivative epoxy resin and (A-2) an acid anhydride, or a prepolymer obtained by reacting them, comprising [(A-1) component Combination or prepolymer having a molar ratio of 0.6 to 2.0, (B) glass fiber, (C) internal mold release Agent, (D) reflection improver, (E) inorganic filler, and (F) curing catalyst in predetermined amounts, the average length of the component (B) is 50 to 400 μm, and the average diameter is 5.0 to 25 μm. An optical semiconductor device comprising: a thermosetting epoxy resin composition; a reflective member for an optical semiconductor device comprising a cured product of the composition; and a reflective member comprising an cured product of the composition and an optical semiconductor element.
[Selection figure] None

Description

  The present invention is excellent in releasability, fluidity and reliability at high temperature storage, has good light resistance, suppresses discoloration due to heat, especially yellowing, and gives a cured product having excellent reflectivity. The present invention relates to a curable epoxy resin composition, a reflecting member for an optical semiconductor device made of a cured product of the composition, and an optical semiconductor device having the reflecting member, a light emitting element, a light receiving element, and other optical semiconductor elements.

  The reliability requirements for the sealing material and the reflecting member of the semiconductor / electronic device are becoming more and more severe due to the reduction in thickness and size as well as the increase in output. As an example, semiconductor elements such as LEDs and LDs (laser diodes) are small and efficiently emit bright colors, and since they are semiconductor elements, there are no ball breaks, excellent drive characteristics, and ON / OFF for vibration. Strong against repeated lighting. Therefore, it is used as various indicators and various light sources.

  Currently, polyphthalamide resin (PPA) is widely used as one of materials for semiconductor and electronic equipment devices such as photocouplers using such semiconductor elements.

  However, due to the dramatic progress of today's optical semiconductor technology, the output power and the wavelength of optical semiconductor devices have been remarkably reduced. Especially in optical semiconductor devices such as photocouplers that can emit or receive high energy light, In a semiconductor element encapsulant and a pre-mold package using a conventional PPA resin as a white material, deterioration due to long-term use is prominent, and color unevenness, peeling, mechanical strength, etc. are likely to occur. It is desired to effectively solve such problems.

  More specifically, in Japanese Patent No. 2656336 (Patent Document 1), a B-stage epoxy resin composition for encapsulating an optical semiconductor, in which the sealing resin comprises an epoxy resin, a curing agent and a curing accelerator as constituent components. An optical semiconductor device characterized in that it is composed of a cured body of a resin composition in which the constituent components are uniformly mixed at the molecular level is described. In this case, as the epoxy resin, bisphenol A type epoxy resin or bisphenol F type epoxy resin is mainly used, and it is also described that triglycidyl isocyanate or the like can be used, but triglycidyl isocyanate is a bisphenol type in Examples. A small amount is added to the epoxy resin, and according to the study by the present inventors, this epoxy resin composition for B-stage semiconductor encapsulation has a problem that it turns yellow particularly when left at high temperature for a long time. is there.

  Moreover, about use of the triazine derivative epoxy resin in the epoxy resin composition for light emitting element sealing, Unexamined-Japanese-Patent No. 2000-196151 (patent document 2), Unexamined-Japanese-Patent No. 2003-224305 (patent document 3), and Unexamined-Japanese-Patent No. 2005. Although described in Japanese Patent No. 306952 (Patent Document 4), none of these is B-staged using a triazine derivative epoxy resin and an acid anhydride. Further, the combination of the triazine derivative epoxy resin and the acid anhydride has a drawback that the mechanical strength is low.

  In addition, as well-known literature relevant to this invention, in addition to said gazette, the following patent documents 5-7 and nonpatent literature 1 are mentioned.

Japanese Patent No. 2656336 JP 2000-196151 A JP 2003-224305 A JP 2005-306952 A Japanese Patent No. 3512732 JP 2001-234032 A JP 2002-302533 A

Special Issue on Electronics Packaging Technology 2004.4

  The present invention has been made in view of the above circumstances, and is a thermosetting epoxy resin that retains reflectivity (that is, whiteness), heat resistance, and light resistance for a long period of time and provides a cured product with excellent mechanical strength. It aims at providing the reflecting member which consists of a composition, the hardened | cured material of this composition, and the optical semiconductor device which has this reflecting member.

As a result of intensive studies to achieve the above object, the present inventors have reached the present invention. That is, the present invention firstly
(A) (A-1) A combination of a triazine derivative epoxy resin and (A-2) an acid anhydride, or a prepolymer obtained by reacting these, [the epoxy group possessed by the component (A-1) ] A combination or prepolymer having a molar ratio of [an acid anhydride group of (A-2) component] of 0.6 to 2.0,
(B) glass fiber,
(C) an internal release agent,
(D) a reflection improver,
(E) containing an inorganic filler, and (F) a curing catalyst,
For a total of 100 parts by mass of the component (A-1) and the component (A-2),
10 to 200 parts by mass of the component (B),
0.2 to 10.0 parts by mass of the component (C),
50 to 800 parts by mass of the component (D),
50 to 1,000 parts by mass of the component (E), and
A thermosetting epoxy resin composition containing 0.05 to 5.0 parts by mass of the component (F),
The said composition whose average length of the glass fiber of said (B) component is 50-400 micrometers and whose average diameter is 5.0-25 micrometers is provided.

  According to this thermosetting epoxy resin composition, it is possible to obtain a cured product that retains whiteness, heat resistance, and light resistance over a long period of time and has excellent mechanical strength.

  Since the cured product obtained by curing the epoxy resin composition according to the present invention has high whiteness and is excellent in light reflectivity, it is useful as a reflective member used in an optical semiconductor device. That is, the present invention secondly provides a reflecting member for an optical semiconductor device comprising a cured product of the above composition.

  Thirdly, the present invention provides an optical semiconductor device having a reflecting member made of a cured product of the above composition and an optical semiconductor element.

  The thermosetting epoxy resin composition of the present invention is excellent in fluidity, reflow resistance, reliability at high temperature storage, releasability, excellent mechanical strength, and maintains light resistance over a long period of time. And a cured product with little yellowing. Further, the cured product of the present composition is particularly suitable for a reflective member such as a pre-mold package because it has excellent mechanical strength, hardly discolors by light, and has good reflectivity after reflow.

It is a schematic sectional drawing of the semiconductor device which mounted the semiconductor element in the premold package formed with the composition of this invention, and was resin-sealed. It is a schematic sectional drawing which shows the flip-chip-type LED element structure which coat | covered the one part surface of the board | substrate and the submount with the film-form reflective member formed with the composition of this invention.

<(A) Combination of epoxy resin and acid anhydride or reaction product thereof (prepolymer)>
The thermosetting epoxy resin composition according to the present invention comprises (A-1) a triazine derivative epoxy resin and (A-2) an acid anhydride [an epoxy group contained in the component (A-1)] / [(A -2) The reaction product obtained by making it react by the molar ratio 0.6-2.0 of the acid anhydride group which a component has] is used as a resin component.

-(A-1) Triazine derivative epoxy resin-
The prepolymer obtained by reacting the (A-1) component triazine derivative epoxy resin with (A-2) acid anhydride at a specific ratio is added as a resin component to the thermosetting epoxy resin composition according to the present invention. Thus, an optical semiconductor device in which yellowing of the cured product of the composition is suppressed and deterioration with time is small is realized. Such triazine derivative epoxy resins are preferably 1,3,5-triazine derivative epoxy resins (for example, isocyanurate ring-containing epoxy resins, cyanurate ring-containing epoxy resins, etc.). In particular, an epoxy resin having an isocyanurate ring is excellent in light resistance and electrical insulation, and is divalent (that is, two), more preferably trivalent (that is, one isocyanurate ring). It is desirable to have 3) epoxy groups. Specifically, tris (2,3-epoxypropyl) isocyanurate, tris (γ-glycidoxypropyl) isocyanurate, tris (α-methylglycidyl) isocyanurate, or the like can be used.

  The softening point of the (A-1) component triazine derivative epoxy resin is preferably 90 to 125 ° C. In addition, in this invention, the triazine derivative epoxy resin of (A-1) component does not include what hydrogenated the triazine ring. (A-1) The triazine derivative epoxy resin of a component may be used individually by 1 type, and may use 2 or more types together.

-(A-2) Acid anhydride-
The acid anhydride (that is, carboxylic acid anhydride) of the component (A-2) used in the present invention acts as a curing agent. The acid anhydride is preferably non-aromatic and does not have a carbon-carbon double bond so that the cured product has light resistance. For example, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, Examples include alkyltetrahydrophthalic anhydride and hydrogenated methyl nadic anhydride. Among these, methylhexahydrophthalic anhydride is more preferable. (A-2) The acid anhydride of a component may be used individually by 1 type, and may use 2 or more types together.

  The blending amount of the acid anhydride is such that the molar ratio of [epoxy group possessed by component (A-1)] / [acid anhydride group possessed by component (A-2)] is 0.6 to 2.0, preferably The amount is 1.0 to 2.0, more preferably 1.2 to 1.6. If the molar ratio is less than 0.6, poor curing is likely to occur and reliability may be lowered. Moreover, when it exceeds 2.0, an unreacted acid anhydride may remain in a hardened | cured material and may deteriorate the moisture resistance of the hardened | cured material obtained.

The prepolymer of component (A) is prepared, for example, as follows.
(I) The component (A-1) and the component (A-2), or the component (A-1), the component (A-2), and the antioxidant to be described later are preliminarily 70 to 120 ° C., preferably The reaction is carried out at 80 to 110 ° C. for 4 to 20 hours, preferably 6 to 15 hours. Or (ii) the curing catalyst of the component (A-1), the component (A-2) and the component (F), or the component (A-1), the component (A-2), an antioxidant described later, And the curing catalyst of (F) component is made to react beforehand at 30-80 degreeC, Preferably it is 40-60 degreeC for 10-72 hours, Preferably it is 36-60 hours. In this way, a solid containing the prepolymer as the component (A) is obtained. The solid material preferably has a softening point of 50 to 100 ° C, more preferably 60 to 90 ° C. This is preferably pulverized and blended with other components to prepare a composition.

  It is desirable in terms of handling and workability that the softening point of the solid is in the range of 50 to 100 ° C. If the softening point is too low, it is difficult to handle even a solid substance, and if it is too high, it is difficult to obtain the desired appropriate fluidity when heated. Since the softening point depends on the amount and molecular weight of the polymer component in the reaction product, it is desirable to select the reaction temperature and reaction time so that an appropriate softening point can be obtained. In the present invention, the softening point is a value measured according to a softening point test method (ring ball method) defined in JIS K 2207.

  The solid obtained here is mainly composed of a prepolymer of the triazine derivative epoxy resin as the component (A-1) and the acid anhydride as the component (A-2), but gel permeation chromatography. In the analysis by (GPC) (however, the sample concentration: 0.2% by mass, injection amount: 50 μl, mobile phase: 100% THF, flow rate: 1.0 ml / min., Temperature: 40 ° C. under the analysis conditions) As measured by using a RI (differential refractometer)), a high molecular weight component having a polystyrene-equivalent weight average molecular weight (hereinafter simply referred to as “average molecular weight”) exceeding 1,500, and an average molecular weight of 300 to 1,500 It contains a molecular weight component and a monomer component, the high molecular weight component is 20 to 70% by mass, the medium molecular weight component is 10 to 60% by mass, and the monomer component is 10 to 40% by mass. Masui. The presence of the monomer component improves the fluidity when the solid is heated to form a premold package or the like.

  When the above-mentioned solid substance uses triglycidyl isocyanurate (that is, tris (2,3-epoxypropyl) isocyanurate) as the component (A-1), it contains a prepolymer represented by the following formula (1), In particular, when the acid anhydride of the component (A-2) is methylhexahydrophthalic anhydride, it contains a prepolymer represented by the following formula (2).

In the above formula, R ¹ represents an acid anhydride residue, and m is a number from 0 to 200, preferably from 0 to 100. The prepolymer represented by the above formula (1) or (2) usually has an average molecular weight of 500 to 100,000, but the solid containing the prepolymer has a molecular weight of 300 to 1, as described above. The medium molecular weight component of 500 is preferably 10 to 60% by mass, particularly 10 to 40% by mass, and the monomer component (unreacted epoxy resin and acid anhydride) is preferably 10 to 40% by mass, and particularly preferably 15 to 30% by mass.

<(B) Glass fiber>
Glass fiber is blended in the epoxy resin composition of the present invention. (B) The glass fiber of a component is mix | blended in order to raise the mechanical strength of hardened | cured material. Component (B) can be used alone or in combination of two or more.

  The glass fiber of component (B) is obtained by quenching molten glass while stretching it by various methods to form a thin fiber having a predetermined diameter. The glass fiber of component (B) includes roving in which strands obtained by bundling single fibers with a sizing agent are uniformly drawn into bundles, and pulverized products such as strands and rovings. As the glass fiber of the component (B), for example, chopped strand made of E glass is used.

  (B) The average diameter of the glass fiber of a component is 5.0-25 micrometers, Preferably it is 8.0-15 micrometers. If the average diameter is too thin, the mechanical strength of the cured product may not be sufficiently improved, and if it is too thick, workability may be reduced during production of the composition.

  Moreover, the length of the glass fiber added at the time of manufacture of an epoxy resin composition is important as one of the factors affecting the length of the glass fiber remaining in the composition. In this invention, the average length of the glass fiber added at the time of manufacture of an epoxy resin composition as (B) component is 50-400 micrometers, Preferably it is 60-300 micrometers. When the average length of the component (B) is within the above range, the length of the glass fiber present in the resulting epoxy resin composition does not affect the molding of the composition, and the cured product obtained Tends to be long enough to maintain the mechanical strength. If the average length of the glass fibers added during the production of the epoxy resin composition is too short, the length of the glass fibers remaining in the resulting composition will be too short, and the mechanical strength of the resulting cured product will be reduced. There is. Moreover, when the average length of the glass fiber added at the time of manufacture of an epoxy resin composition is too long, workability | operativity may fall at the time of manufacture of a composition.

  The average length and the average diameter of the glass fiber are the average value of the length of the glass fiber and the average value of the diameter measured by observation with an electron microscope, respectively. The number of glass fibers used for the measurement is, for example, 100.

  The filling amount of the glass fiber of (B) component is 10-200 mass parts with respect to 100 mass parts of total amounts of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride, and is 15-100 masses. Part is preferred. If it is less than 10 parts by mass, it is difficult to obtain a cured product having sufficient mechanical strength, and if it exceeds 200 parts by mass, the moldability tends to decrease due to unfilling and voids being easily generated.

<(C) Internal mold release agent>
An internal mold release agent is mix | blended with the epoxy resin composition of this invention. The internal mold release agent of component (C) is blended in order to improve the mold release property at the time of molding. Component (C) can be used alone or in combination of two or more.
As the internal mold release agent of the component (C), the following general formula (3):

〔式中、Ｒ¹、Ｒ²、Ｒ³は、独立に、Ｈ、−ＯＨ、−ＯＲ、又は−ＯＣＯＣ_aＨ_bであり、Ｒ¹、Ｒ²、Ｒ³の少なくともひとつは−ＯＣＯＣ_aＨ_bである。ＲはＣ_nＨ_2n+1のアルキル基（ｎは１〜３０の整数である。）、ａは１０〜１００の整数、ｂは１７〜２０１の整数である。〕
で示され、且つ融点が５０〜７０℃の範囲である化合物を含むことが好ましい。

[Wherein, R ¹ , R ² , R ³ are independently H, —OH, —OR, or —OCOC _a H _b , and at least one of R ¹ , R ² , R ³ is —OCOC _a H _b . R is an alkyl group of C _n H _{2n + 1} (n is an integer of 1 to 30), a is an integer of 10 to 100, and b is an integer of 17 to 201. ]
And a compound having a melting point in the range of 50 to 70 ° C.

  As internal mold release agents, natural waxes such as carnauba wax; synthetic waxes such as acid wax, polyethylene wax, and fatty acid ester are known, but many of these are generally easy under high temperature conditions or under light irradiation. It turns yellow and deteriorates with time and loses its releasability. On the other hand, the compound represented by the general formula (3) has a low yellowing property even when left at a high temperature and under light irradiation, and continuously maintains a good releasability over a long period of time.

It is essential that at least one of R ¹ , R ² and R ^{3 in} the general formula (3) is —OCOC _a H _b . When all are —OH, sufficient releasability and heat resistance cannot be obtained, but by including —OCOC _a H _b in the structure, good compatibility with other components, particularly the above prepolymer, cured product Good heat resistance and releasability can be obtained.

A contained in —OCOC _a H _b is an integer of 10 to 100, preferably an integer of 10 to 30, and more preferably an integer of 11 to 20. If a is less than 10, sufficient heat-resistant yellowing may not be obtained, and if a exceeds 100, it may not be sufficiently compatible with other components and a good release effect may not be obtained.

C _a H _b is a saturated or unsaturated aliphatic hydrocarbon group. In the case of unsaturation, those having one or two unsaturated bonds are preferred, and therefore b = 2a + 1, 2a-1 or 2a-3 is preferred, and in particular b = 2a + 1 or 2a-1. Is preferred. From this point, b is an integer of 17 to 201, preferably an integer of 19 to 61, more preferably an integer of 21 to 61, and particularly preferably an integer of 23 to 41.

  Specifically, glycerol fatty acid esters such as glycerol monopalmitate, glycerol monostearate, glycerol mono12-hydroxystearate, glycerol tri12-hydroxystearate, glycerol monobehenate; propylene glycol monopalmitate, propylene glycol mono Examples thereof include propylene glycol fatty acid esters such as stearate and propylene glycol monobehenate.

  However, the melting point and volatile content at high temperature are also important factors affecting the heat resistance. Melting | fusing point becomes like this. Preferably it is 50-90 degreeC, More preferably, it is 65-85 degreeC. Moreover, a volatile matter at 250 ° C. is preferably 10% by mass or less. When the melting point is 50 to 90 ° C., the compatibility with other components is likely to be sufficient, a good mold release effect is easily exhibited, and a cured product having sufficient heat-resistant yellowing is easily obtained. In particular, glycerin fatty acid ester (specifically, glycerin monostearate) and propylene glycol fatty acid ester (specifically, glycerin monostearate) having a melting point of 50 to 70 ° C. in terms of dispersibility in the composition and compatibility with other components. Propylene glycol monobehenate) is preferred.

  The internal mold release agent of component (C) preferably contains the compound represented by the general formula (3) in a proportion of 20 to 100% by mass, particularly 50 to 100% by mass.

In the case of using another compound in combination with the compound represented by the general formula (3) as the internal mold release agent of the component (C), the following general formula (4):
R ⁴ —COO—R ⁵ (4)
(In the formula, R ⁴ and R ⁵ are the same or different alkyl groups represented by C _n H _{2n + 1} , and n is an integer of 1-30, preferably 2-28, more preferably 5-25. .)
It is preferable to use together with the carboxylic acid ester shown by. Examples of other mold release agents include the natural wax, acid wax, and other synthetic waxes described above.

  The carboxylic acid ester of the general formula (4) is also low in yellowing even when left at a high temperature and under light irradiation, and continuously maintains good releasability over a long period of time. In this case, the mass ratio of the carboxylic acid ester of the general formula (4): the compound of the general formula (3) is preferably 1: 5 to 10: 1, more preferably 1: 4 to 8: 1. When the mass ratio is within the above range, it is easy to maintain the adhesiveness between the cured product and the metal frame and the mechanical strength of the cured product.

  The amount of the internal release agent (C) added is 0.2 to 10.0 parts by mass with respect to 100 parts by mass of the total amount of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride. Yes, 0.5-5.0 mass parts is preferable. If the addition amount is less than 0.2 parts by mass, sufficient releasability may not be obtained, and if it exceeds 10.0 parts by mass, sufficient releasability may not be obtained due to poor curing. In addition, adhesion failure with a metal frame may occur.

<(D) Reflection improver>
A reflection improving agent is mix | blended with the epoxy resin composition of this invention. (D) The reflection improving agent of a component is mix | blended in order to improve the light reflectivity in hardened | cured material surface by improving the whiteness of hardened | cured material as a white colorant. Component (D) can be used alone or in combination of two or more.

  As the reflection improver, a white pigment is preferable, and titanium dioxide is preferable, and a rutile type is particularly preferable in terms of weather resistance. Examples of white pigments other than titanium dioxide include potassium titanate, zircon oxide, zinc sulfide, zinc oxide, and magnesium oxide. White materials other than titanium dioxide are preferably used in combination with titanium dioxide.

Although not particularly limited, the average particle diameter of the component (D) is typically 0.05 to 5.0 μm. Here, the average particle diameter can be obtained as a cumulative mass average value D ₅₀ (or median diameter) in particle size distribution measurement by a laser light diffraction method.

  Starting with the above titanium dioxide, the reflection improver of component (D) is an inorganic substance and / or organic substance such as an Al compound, Si compound, polyol, etc. in order to improve the mixing and dispersibility with the resin component and the inorganic filler and the weather resistance. The surface treatment may be performed in advance, and it is particularly preferable to treat with at least one of an Al compound, a Si compound and a polyol. Examples of the Al compound include sodium aluminate. Examples of the Si compound include organosilicon compounds such as alkoxysilanes or partial hydrolysis condensates thereof. Examples of the polyol include trimethylolpropane.

  Moreover, it is preferable to use titanium dioxide with little content of lead for (D) component of this invention. In terms of environmental measures, titanium dioxide with a high lead content may be restricted in use, and surprisingly, the lead content may affect the light reflectivity of the cured epoxy resin. The lead content is preferably less than 10 ppm (that is, not less than 0 ppm and less than 10 ppm), more preferably not more than 5 ppm (that is, 0 to 5 ppm), particularly preferably not more than 2 ppm (that is, 0 to 2 ppm), Furthermore, 1 ppm or less (namely, 0-1 ppm) is preferable. Specific examples of such titanium dioxide include CR-95 (trade name, lead content 1 ppm (mass basis)) manufactured by Ishihara Sangyo, but are not particularly limited.

  (D) The filling amount of the reflection improver of the component is 50 to 800 parts by mass with respect to 100 parts by mass of the total amount of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride, and 60 to 600 parts. Part by mass is preferred. If it is less than 50 parts by mass, it is difficult to obtain a cured product having sufficient whiteness, and if it exceeds 800 parts by mass, the moldability tends to decrease due to unfilling and voids being likely to occur.

<(E) Inorganic filler>
An inorganic filler is further blended in the epoxy resin composition of the present invention. The component (E) can be used alone or in combination of two or more. (E) As an inorganic filler of a component, what is normally mix | blended with an epoxy resin composition can be used. For example, silicas such as fused silica and crystalline silica, alumina, silicon nitride, aluminum nitride, boron nitride, antimony trioxide and the like can be mentioned, but glass fiber used as component (B) and used as component (D) White pigments are excluded.

(E) Although the average particle diameter and shape of the inorganic filler of a component are not specifically limited, Preferably an average particle diameter is 5-75 micrometers. Here, the average particle diameter can be obtained as a cumulative mass average value D ₅₀ (or median diameter) in particle size distribution measurement by a laser light diffraction method.

  The inorganic filler of component (E) may be one that has been surface-treated in advance with a coupling agent such as a silane coupling agent or a titanate coupling agent in order to increase the bond strength between the resin component and the inorganic filler.

  Examples of such a coupling agent include epoxy functions such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane. Functional alkoxysilanes such as N-β (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, and γ-mercapto It is preferable to use a mercapto functional alkoxysilane such as propyltrimethoxysilane. The amount of coupling agent used for the surface treatment and the surface treatment method are not particularly limited.

  The filling amount of the inorganic filler is preferably 50 to 1,000 parts by weight, particularly preferably 80 to 800 parts by weight with respect to 100 parts by weight of the total amount of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride. . If the amount is less than 50 parts by mass, the strength of the cured product may be insufficient. If the amount exceeds 1,000 parts by mass, the resulting composition may be thickened, resulting in poor filling and loss of flexibility of the cured product. Defects such as peeling of the reflecting member formed of the composition may occur in the semiconductor device.

<(F) Curing catalyst>
As a curing catalyst of (F) component, a well-known thing can be used as a curing catalyst of an epoxy resin composition, and it is not specifically limited. Component (F) can be used alone or in combination of two or more. Examples of the component (F) include tertiary amines; imidazoles; organic carboxylates thereof; organic carboxylic acid metal salts; metal-organic chelate compounds; aromatic sulfonium salts, organic phosphine compounds, and phosphonium compounds. And phosphorus-based curing catalysts such as salts of these phosphorus compounds. Among these, imidazoles (for example, 2-ethyl-4-methylimidazole), phosphorus-based curing catalysts (for example, quaternary phosphonium bromide, methyl-tributylphosphonium-dimethyl phosphate), octyl acids of tertiary amines Salts are preferred. A combination of quaternary phosphonium bromide and an organic acid salt of amine is also preferably used.

  The usage-amount of a curing catalyst is 0.05-5.0 mass parts with respect to 100 mass parts of total amounts of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride, and 0.1-3 0.0 part by mass is preferred. If the amount used is out of the above range, the balance between the heat resistance and moisture resistance of the cured product of the epoxy resin composition may be deteriorated.

<Other ingredients>
In addition to the components (A) to (F), other components can be added to the epoxy resin composition of the present invention as necessary, as long as the effects of the present invention are not impaired. Other components include, for example, epoxy resins other than the component (A-1), antioxidants, various thermoplastic resins, thermoplastic elastomers, organic compounds for the purpose of improving the properties of the composition of the present invention or cured products thereof. Examples thereof include additives such as a low stress agent such as a synthetic rubber and a halogen trap agent. Other components can be used alone or in combination of two or more.

-Epoxy resins other than (A-1) component-
The epoxy resin other than the component (A-1) to be blended in the composition of the present invention as necessary is a certain amount or less (particularly, 100 parts by weight of the component (A-1) within a range not impairing the effects of the present invention 0 to 40 parts by weight, particularly 5 to 20 parts by weight). Epoxy resins other than the component (A-1) can be used singly or in combination of two or more.

  Examples of epoxy resins other than the component (A-1) include bisphenol A type epoxy resin, bisphenol F type epoxy resin, 3,3 ′, 5,5′-tetramethyl-4,4′-biphenol type epoxy resin, 4 Biphenol type epoxy resin such as 4,4'-biphenol type epoxy resin; Novolak type epoxy resin such as phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin; naphthalenediol type epoxy resin; Examples thereof include a methane type epoxy resin; a tetrakisphenylolethane type epoxy resin; and an epoxy resin obtained by hydrogenating an aromatic ring of a phenol dicyclopentadiene novolac type epoxy resin. The softening point of the epoxy resin other than the component (A-1) is preferably 70 to 100 ° C.

-Antioxidant-
An antioxidant may be added to the composition of the present invention to prevent deterioration of the composition or its cured product. Antioxidants can be used singly or in combination of two or more. Examples of the antioxidant include a phenolic antioxidant, a phosphorus antioxidant, and a sulfur antioxidant.

  Examples of phenolic antioxidants include pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,6-di-t-butyl-p-cresol, butylated hydroxy Anisole, 2,6-di-t-butyl-p-ethylphenol, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2′-methylenebis (4-methyl- 6-t-butylphenol), 4,4′-butylidenebis (3-methyl-6-t-butylphenol), 3,9-bis [1,1-dimethyl-2- {β- (3-t-butyl-4) -Hydroxy-5-methylphenyl) propionyloxy} ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane, 1,1,3-tris (2 -Methyl-4-hydroxy-5-t-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene and the like Can be mentioned. Among these, pentaerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] is preferable from the viewpoint of heat resistance and strength of the obtained cured product.

  Phosphorus antioxidants include triphenyl phosphite, diphenylalkyl phosphite, phenyl dialkyl phosphite, tri (nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol Diphosphite, tris (2,4-di-tert-butylphenyl) phosphite, diisodecylpentaerythritol diphosphite, di (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tristearyl sorbitol triphos Phyto and tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenyl diphosphonate can be mentioned, among which triphenyl phosphite is preferable.

  Examples of the sulfur-based antioxidant include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, and the like.

  The compounding quantity of antioxidant is 0.02-7 mass parts with respect to 100 mass parts of total amounts of (A-1) triazine derivative epoxy resin and (A-2) acid anhydride, and is 0.03-5 mass. Part. If the blending amount is too small, it may be difficult to obtain a cured product having sufficient heat resistance, and the cured product may be discolored. If the blending amount is too large, the composition tends to cause curing inhibition, and a composition having sufficient curability and sufficient It may not be possible to obtain a cured product having a sufficient strength.

<Preparation of composition>
As a method for preparing the epoxy resin composition of the present invention as a molding material, for example, the components (A-1) and (A-2) are mixed in advance, and 70 to 120 ° C., preferably 80 to 110 ° C. Or in the temperature range of 30 to 80 ° C., preferably 40 to 60 ° C. by mixing the components (A-1), (A-2) and (F) in advance. The mixture was uniformly melted and mixed by a device such as a reaction vessel capable of being heated, and the mixture was thickened until it became a softening point sufficient for handling at room temperature, specifically 50 to 100 ° C, more preferably 60 to 90 ° C. There is a method of cooling a product to obtain a solidified product. In addition, you may add antioxidant at the time of mixing of each component.

  In this case, as a temperature range for mixing these components, when mixing the components (A-1) and (A-2), 70 to 120 ° C. is appropriate, and more preferably 80 to 110 ° C. . If the temperature is too high, the reaction rate becomes too fast, and it becomes difficult to stop the reaction at the expected reactivity. Moreover, when mixing (A-1), (A-2), and (F) component, 30-80 degreeC is suitable, More preferably, it is the range of 40-60 degreeC. If the temperature is too high, the reaction rate becomes too fast, and it becomes difficult to stop the reaction at the expected reactivity.

  Next, after pulverizing the solid, when the component (F) is not used for the preparation of the solid, the components (B), (C), (D), (E) and (F), If necessary, other components are blended in a predetermined composition ratio. In addition, when the component (F) is used for the preparation of the solid, the components (B), (C), (D), and (E) and, if necessary, other components are blended at a predetermined composition ratio. To do. The resulting mixture is sufficiently uniformly mixed with a mixer, etc., then subjected to a melt mixing process using a hot roll mill, a kneader, an extruder, etc., then cooled and solidified, and then pulverized into particles of an appropriate size to obtain an epoxy resin. It can be a molding material of the composition.

  In this case, the most common method for molding the thermosetting epoxy resin composition of the present invention is a low-pressure transfer molding method. In addition, as for the shaping | molding temperature of the epoxy resin composition of this invention, 150-185 degreeC is desirable, and time may be 30 to 180 second normally. If necessary, post-curing may be performed. In this case, the temperature is preferably 150 to 185 ° C., and the time may be 2 to 20 hours.

<Reflection member>
A typical example of the reflective member formed of the composition of the present invention is a pre-mold package. In the example shown in FIG. 1, the pre-mold package 5 is molded on the lead frame 2 with the composition of the present invention, and then the semiconductor element 1 is placed on the lead frame 2. After the element 1 is connected to an electrode (not shown) with a bonding wire 3, the element 1 is sealed with a transparent sealing body 4 made of a transparent resin, and a lens 6 is formed at the same time.

  Examples of the reflective member other than the pre-mold package are not particularly limited as long as it is a member to which light reflectivity is desired. For example, in the case of a light emitting element such as an LED element, a member that covers the periphery of a sealing body made of a transparent resin, a base substrate, a submount, etc. so that light is emitted only in a specific direction (for example, upward) Examples thereof include a film-like member that covers at least a part of the surface of another constituent member.

  For example, FIG. 2 shows a flip chip type LED device structure. A submount 22 is formed on the base substrate 21. On the other hand, a high-growth AlN buffer layer 24, an n-contact layer (GaN: Si) 25, a DH structure (light emitting portion) 26, and a p-contact layer (GaN: Mg) 27 are sequentially formed on the sapphire substrate 23. The p-electrode 28 on the p-contact layer 27 is connected to the submount 22 via the Au bump 29a, and the n-electrode 30 on the n-contact layer 25 is connected to the submount 22 via the Au bump 29b. It is connected to the. And a part of submount 22 is coat | covered with the film-form reflective member 31 formed with this invention composition. Further, the entire element is sealed with a transparent sealing body 32 made of silicone resin. The reflection efficiency on the surface of the submount 22 is significantly improved by the reflection member 31.

EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.
The raw materials used in the following examples are shown below.

(A)
(A-1) Triazine derivative epoxy resin Tris (2,3-epoxypropyl) isocyanurate (trade name: TEPIC-S, manufactured by Nissan Chemical Industries, Ltd., epoxy equivalent 100)
(A-2) Acid anhydride Methylhexahydrophthalic anhydride (trade name: Ricacid MH, manufactured by Shin Nippon Rika Co., Ltd., acid anhydride having no carbon-carbon double bond)

(B) Glass fiber Chopped strand made of E glass having an average length of 200 μm, 30 μm, 600 μm or 1300 μm and a diameter of 13 μm

(C) Internal mold release agent (C-1) Propylene glycol monobehenate (trade name: PB-100, manufactured by Riken Vitamin Co., Ltd., melting point 57 ° C.)
(C-2) Stearyl stearate (trade name: SL-900A, manufactured by Riken Vitamin Co., Ltd., melting point 55 ° C.)

(D) Reflection improver
Chlorinated titanium dioxide surface-treated with at least one of Al compound, Si compound and polyol (trade name: CR-95, manufactured by Ishihara Sangyo Co., Ltd., rutile type, lead content 1 ppm (mass basis))
(E) Inorganic filler Spherical fused silica (manufactured by Tatsumori)
(F) Curing catalyst Quaternary phosphonium bromide (trade name: U-CAT5003, manufactured by San Apro Co., Ltd.)

[Examples 1 to 3, Comparative Examples 1 to 5]
In each example, the triazine derivative epoxy resin and acid anhydride were placed in a reaction kettle, melt mixed at 100 ° C. for 3 hours, then cooled and solidified to obtain a solid with a softening point of 60 ° C. The solid was pulverized into powder. The powdered solid was blended with the other components at the composition ratio shown in Table 1, and was uniformly melt-mixed with a two-roll hot mill, cooled and pulverized to obtain a white epoxy resin composition.
The following properties were measured for these compositions. The results are shown in Table 1.

《Workability during manufacturing》
The workability at the time of melt mixing by the above-described hot two-roll mill was evaluated according to the following criteria.
○: It was easy to mix each component uniformly, and a composition could be obtained.
X: It was difficult to mix each component uniformly, and the composition could not be obtained.

<Spiral flow value>
Measurement was performed under the conditions of 175 ° C., 6.9 N / mm ² and a molding time of 120 seconds using a mold conforming to the EMMI standard.

《Bending strength》
A cured product having a thickness of 4 mm, a width of 10 mm, and a length of 100 mm was molded under conditions of 175 ° C., 6.9 N / mm ² , and a molding time of 120 seconds. After secondary curing at 150 ° C. for 2 hours, thermosetting Plastic general test method Measured at room temperature based on JIS K 6911.

《Light reflectivity》
A disk (cured product) having a diameter of 50 mm and a thickness of 3 mm was molded under the conditions of 175 ° C., 6.9 N / mm ² and a molding time of 120 seconds. The light reflectance was measured immediately after molding. Thereafter, the disk was irradiated with UV of 60 mW / cm ² from a high pressure mercury lamp having a peak wavelength of 365 nm for 24 hours. The light reflectance was measured after UV irradiation. Next, the disk was stored at 180 ° C. for 4 hours, and then the light reflectance was measured. The light reflectance was measured at a wavelength of 450 nm using a spectrocolorimeter (trade name: X-rite 8200, manufactured by SDG Co., Ltd.).

＊１：組成物を得ることができず成形不可
＊２：硬化物が脆すぎて曲げ強度の測定不可

* 1: The composition cannot be obtained and cannot be molded. * 2: The cured product is too brittle and the bending strength cannot be measured.

  As shown in Table 1, in Comparative Examples 2 and 3 in which the average length of the glass fibers was too long, workability during production was poor, and an epoxy resin composition could not be obtained. Moreover, the hardened | cured material which has sufficient mechanical strength was not obtained from the epoxy resin composition of the comparative example 1 in which the average length of glass fiber is too short, and the comparative example 4 in which the addition amount of glass fiber is too small. Furthermore, the cured product obtained from the epoxy resin composition of Comparative Example 5 in which no glass fiber was added was too brittle to measure the mechanical strength. In contrast, the epoxy resin composition of Example 1 included in the present invention was excellent in workability during production, and the cured product obtained from the composition was excellent in mechanical strength.

  The epoxy resin composition of the present invention is useful for forming a reflective member for an optical semiconductor device.

DESCRIPTION OF SYMBOLS 1 Semiconductor element 2 Lead frame 3 Bonding wire 4 Transparent sealing body 5 Premold package 6 Lens 21 Base substrate 22 Submount 23 Sapphire substrate 24 High growth AlN buffer layer 25 n-contact layer 26 DH structure 27 p-contact layer 28 p -Electrode 29a Au bump 29b Au bump 30 n-electrode 31 Film-like reflective member 32 Transparent encapsulant

Claims (15)

(A) (A-1) A combination of a triazine derivative epoxy resin and (A-2) an acid anhydride, or a prepolymer obtained by reacting these, [the epoxy group possessed by the component (A-1) ] A combination or prepolymer having a molar ratio of [an acid anhydride group of (A-2) component] of 0.6 to 2.0,
(B) glass fiber,
(C) an internal release agent,
(D) a reflection improver,
(E) containing an inorganic filler, and (F) a curing catalyst,
For a total of 100 parts by mass of the component (A-1) and the component (A-2),
10 to 200 parts by mass of the component (B),
0.2 to 10.0 parts by mass of the component (C),
50 to 800 parts by mass of the component (D),
50 to 1,000 parts by mass of the component (E), and
A thermosetting epoxy resin composition containing 0.05 to 5.0 parts by mass of the component (F),
The said composition whose average length of the glass fiber of said (B) component is 50-400 micrometers, and an average diameter is 5.0-25 micrometers.   The composition according to claim 1, wherein the triazine derivative epoxy resin as the component (A-1) is a 1,3,5-triazine derivative epoxy resin. The prepolymer of the component (A) is represented by the following general formula (1):

(In the formula, R ¹ represents an acid anhydride residue, and m is a number from 0 to 200.)
The composition which concerns on 1 or 2 containing the compound shown by these.   The composition which concerns on any one of Claims 1-3 in which the internal mold release agent of the said (C) component contains the glycerol monostearate whose melting | fusing point is 50-70 degreeC.   The composition according to any one of claims 1 to 4, wherein the reflection enhancer of the component (D) is titanium dioxide powder.   The composition according to claim 5, wherein the lead content of the titanium dioxide powder is less than 10 ppm on a mass basis.   The composition which concerns on any one of Claims 1-5 by which the reflection improving agent of the said (D) component is processed by at least 1 sort (s) of Al compound, Si compound, and a polyol.   The composition according to any one of claims 1 to 7, which is used for forming a reflective member constituting an optical semiconductor device.   The composition according to claim 8, wherein the reflecting member is a pre-mold package.   The reflection member for optical semiconductor devices which consists of hardened | cured material of the composition of any one of Claims 1-7.   The reflective member according to claim 10, which is a pre-mold package.   The reflecting member according to claim 10, wherein the reflecting member has a film shape covering at least a part of the surface of another constituent member.   The optical semiconductor device which has a reflection member and optical semiconductor element which consist of hardened | cured material of the composition of any one of Claims 1-7.   The optical semiconductor device according to claim 13, wherein the reflecting member is a pre-mold package on which the optical semiconductor element is mounted.   The optical semiconductor device according to claim 13, wherein the reflecting member has a film shape covering at least a part of the surface of another constituent member.

Images