Thermosetting resin composition for light reflection, substrate for mounting optoelectronic semiconductor devices, and optoelectronic semiconductor device.

Abstract

A thermosetting resin composition for optical reflection according to the present disclosure includes an epoxy resin, a curing agent, an inorganic filler, and a white pigment. The inorganic filler contains inorganic hollow particles having a central particle size of 1-25 μｍ.

Description

[Technical Field]

[0001] The present invention relates to a thermosetting resin composition for light reflection, a substrate for mounting an optoelectronic semiconductor device, and an optoelectronic semiconductor device. [Background technology]

[0002] Optoelectronic devices, which combine light-emitting diodes (LEDs) and phosphors, are highly energy-efficient and have long lifespans, leading to their use in a variety of applications such as outdoor displays, mobile LCD backlights, and automotive applications, and demand for them is expanding. Along with this, LED devices are becoming brighter, creating a need to prevent the rise in junction temperature due to increased heat generation from the devices, or the degradation of optoelectronic devices due to increased direct light energy.

[0003] Patent Document 1 discloses a substrate for mounting optical semiconductor devices using a thermosetting resin composition that has high reflectivity in the visible to near-ultraviolet light region after resin curing. Patent Document 2 discloses a component for mounting optical semiconductor devices with reduced light leakage. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2012-254633 [Patent Document 2] Japanese Patent Publication No. 2010-287837 [Overview of the project] [Problems that the invention aims to solve]

[0005] Substrates for mounting optoelectronic semiconductor elements used in fields such as outdoor lighting and automotive headlights require not only high light reflectivity but also excellent mechanical properties such as bending strength.

[0006] Therefore, the present invention aims to provide a thermosetting resin composition for light reflection that can form a cured product with excellent light reflectivity and mechanical properties, a substrate for mounting optical semiconductor elements using the same, and an optical semiconductor device. [Means for solving the problem]

[0007] The present invention relates to a thermosetting resin composition for light reflection, comprising an epoxy resin, a curing agent, an inorganic filler, and a white pigment, wherein the inorganic filler comprises inorganic hollow particles with a central particle size of 1 to 25 μm.

[0008] The bulk density of inorganic hollow particles is 0.20–0.36 g / cm³. 3 It may be as follows. Furthermore, the thickness of the outer shell of the inorganic hollow particles may be 0.4 to 1.3 μm. In addition, the pressure resistance strength of the inorganic hollow particles may be 100 MPa or more at 25°C.

[0009] The white pigment may include at least one selected from the group consisting of titanium dioxide, zinc oxide, alumina, magnesium oxide, antimony oxide, and zirconium oxide.

[0010] In another aspect, the present invention relates to a substrate for mounting an optical semiconductor element, comprising a cured product of the above-mentioned light-reflective thermosetting resin composition. The substrate for mounting an optical semiconductor element according to the present invention has a recess composed of a bottom surface and a wall surface, the bottom surface of the recess may be a mounting portion for an optical semiconductor element. In this case, at least a part of the wall surface of the recess is a cured product of the above-mentioned light-reflective thermosetting resin composition. Furthermore, the substrate for mounting an optical semiconductor element according to the present invention may comprise a substrate, a first connection terminal and a second connection terminal provided on the substrate, and a cured product of the above-mentioned light-reflective thermosetting resin composition provided between the first connection terminal and the second connection terminal.

[0011] In yet another aspect, the present invention relates to an optoelectronic device having the above-mentioned substrate for mounting an optoelectronic semiconductor element and an optoelectronic semiconductor element mounted on the substrate for mounting the optoelectronic semiconductor element. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a thermosetting resin composition for light reflection that can form a cured product excellent in light reflectivity and mechanical properties, a substrate for mounting an optoelectronic device using the same, and an optoelectronic device.

Brief Description of the Drawings

[0013] [Figure 1] It is a perspective view showing an embodiment of a substrate for mounting an optoelectronic device. [Figure 2] It is a schematic view showing an embodiment of a process for manufacturing a substrate for mounting an optoelectronic device. [Figure 3] It is a perspective view showing an embodiment of a state in which an optoelectronic device is mounted on a substrate for mounting an optoelectronic device. [Figure 4] It is a schematic cross-sectional view showing an embodiment of an optoelectronic device. [Figure 5] It is a schematic cross-sectional view showing another embodiment of an optoelectronic device. [Figure 6] It is a schematic cross-sectional view showing another embodiment of an optoelectronic device. [Figure 7] It is a schematic cross-sectional view showing an embodiment of a copper-clad laminate. [Figure 8] It is a schematic cross-sectional view showing an example of an optoelectronic device manufactured using a copper-clad laminate. [Figure 9] ​​​​​​​​​​​​In this specification, a numerical range indicated by "~" represents a range that includes the numerical values described before and after "~" as the minimum value and the maximum value, respectively. In the numerical ranges described stepwise in this specification, the upper limit value or the lower limit value of a numerical range at a certain step may be replaced with the upper limit value or the lower limit value of a numerical range at another step. In the numerical ranges described in this specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples. "A or B" means that either one of A and B may be included, or both may be included. The materials exemplified in this specification can be used alone or in combination of two or more, unless otherwise specified. Further, in this specification, (meth)acrylate means at least one of acrylate and its corresponding methacrylate.

[0016] [Thermosetting resin composition for light reflection] The thermosetting resin composition for light reflection of this embodiment contains an epoxy resin, a curing agent, an inorganic filler, and a white pigment, and the inorganic filler contains inorganic hollow particles having a median particle diameter of 1 to 25 μm.

[0017] (Epoxy resin) As the epoxy resin, an epoxy resin generally used in an epoxy resin molding material for sealing electronic components can be used. By containing an epoxy resin, the thermosetting resin composition according to this embodiment can form a cured product having high hardness and flexural strength during heating and improved mechanical properties. Examples of the epoxy resin include epoxy resins obtained by epoxidizing novolak resins of phenols and aldehydes such as phenol novolak type epoxy resin and orthocresol novolak type epoxy resin; diglycidyl ethers such as bisphenol A, bisphenol F, bisphenol S, and alkyl-substituted bisphenol; glycidylamine type epoxy resins obtained by the reaction of polyamines such as diaminodiphenylmethane and isocyanuric acid with epichlorohydrin; linear aliphatic epoxy resins obtained by oxidizing an olefin bond with a peracid such as peracetic acid; and alicyclic epoxy resins. The epoxy resin may be used alone or in combination of two or more.

[0018] Due to their low coloration, epoxy resins may contain diglycidyl isocyanurate, triglycidyl isocyanurate, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, diglycidyl esters of dicarboxylic acids derived from 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, or 1,4-cyclohexanedicarboxylic acid. For similar reasons, diglycidyl esters of dicarboxylic acids such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, methyltetrahydrophthalic acid, nadic acid, and methylnadic acid are also suitable for epoxy resins. Glycidyl esters such as nuclear hydrogenated trimellitic acid and nuclear hydrogenated pyromellitic acid, which have an alicyclic structure with a hydrogenated aromatic ring, may also be included. Epoxy resins may also contain polyorganosiloxanes having epoxy groups, which are produced by heating a silane compound in the presence of an organic solvent, an organic base, and water, and then hydrolyzing and condensing it.

[0019] Commercial epoxy resins may be used. For example, 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate can be obtained from Daicel Corporation under the product names "Celoxide 2021," "Celoxide 2021A," and "Celoxide 2021P," and from Dow Chemical Japan Ltd. under the product names "ERL4221," "ERL4221D," and "ERL4221E." For example, bis(3,4-epoxycyclohexylmethyl)adipate can be obtained from Dow Chemical Japan Ltd. under the product name "ERL4299," and from DIC Corporation under the product name "EXA-7015." As 1-epoxyethyl-3,4-epoxycyclohexane or limonene diepoxide, for example, Mitsubishi Chemical Corporation's product names "jER YX8000", "jER YX8034", and "jER YL7170", and Daicel Corporation's product names "Celoxide 2081", "Celoxide 3000", "Epolid GT301", "Epolid GT401", and "EHPE3150" are available. As trisglycidyl isocyanurate, for example, Nissan Chemical Industries, Ltd.'s product name "TEPIC-S" is available.

[0020] (Hardening agent) As the curing agent, curing agents commonly used in epoxy resin molding materials for electronic component encapsulation can be used. The curing agent is not particularly limited as long as it reacts with the epoxy resin to produce a cured product, but curing agents with little coloration are preferred, and colorless or pale yellow curing agents are more preferred. Examples of curing agents include acid anhydride-based curing agents, isocyanuric acid derivative-based curing agents, and phenol-based curing agents. The curing agent may be used alone or in combination of two or more types.

[0021] Examples of acid anhydride-based curing agents include phthalic anhydride, maleic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, methylnadic anhydride, nadic anhydride, glutaric anhydride, dimethylglutaric anhydride, diethylglutaric anhydride, succinic anhydride, methylhexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and tetracarboxylic dianhydrides represented by the following formula (1).

[0022] [ka] In formula (1), Rx represents a divalent organic group, and n represents an integer from 1 to 10. The divalent organic group may be a divalent saturated hydrocarbon group having a saturated hydrocarbon ring. Examples of saturated hydrocarbons include cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, norbornene, dicyclopentadiene, adamantane, naphthalene hydrogenate, and biphenyl hydrogenate.

[0023] Examples of isocyanuric acid derivatives include 1,3,5-tris(1-carboxymethyl)isocyanurate, 1,3,5-tris(2-carboxyethyl)isocyanurate, 1,3,5-tris(3-carboxypropyl)isocyanurate, and 1,3-bis(2-carboxyethyl)isocyanurate.

[0024] Examples of phenolic curing agents include novolac-type phenolic resins obtained by condensing or co-condensing phenols such as phenol, cresol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, etc., and / or naphthols such as α-naphthol, β-naphthol, dihydroxynaphthalene, etc., with aldehydes such as formaldehyde, benzaldehyde, salicylaldehyde, etc., under an acidic catalyst; phenols and / or naphthols, and dimethoxyp-xylene or bis(methoxymethyl)biphen Examples include phenol aralkyl resins synthesized from yl; aralkyl-type phenol resins such as biphenylene-type phenol aralkyl resins and naphthol-aralkyl resins; dicyclopentadiene-type phenol resins synthesized by copolymerization of phenols and / or naphthols with dicyclopentadiene; triphenylmethane-type phenol resins; terpene-modified phenol resins; paraxylylene and / or metaxylylene-modified phenol resins; melamine-modified phenol resins; and phenol resins obtained by copolymerizing two or more of these.

[0025] In the thermosetting resin composition according to this embodiment, the content of the curing agent may be 10 to 150 parts by mass, 50 to 130 parts by mass, or 60 to 120 parts by mass per 100 parts by mass of epoxy resin.

[0026] The mixing ratio of the curing agent may be such that, per equivalent of epoxy groups in the epoxy resin, the amount of active groups (acid anhydride groups or hydroxyl groups) in the curing agent that can react with the epoxy groups is 0.5 to 2.0 equivalents, 0.6 to 1.5 equivalents, or 0.7 to 1.2 equivalents. If the amount of active groups is 0.5 equivalents or more, the glass transition temperature of the cured product formed from the thermosetting resin composition will be higher, making it easier to obtain a sufficient elastic modulus. On the other hand, if the amount of active groups is 2.0 equivalents or less, the strength after curing will not decrease easily.

[0027] (White pigment) The white pigment is used to impart a white-based color tone to the cured product (molded article) obtained from the thermosetting resin composition according to this embodiment. In particular, by making the color tone highly white, the light reflectance of the molded article can be improved.

[0028] Examples of white pigments include rare earth oxides such as yttrium oxide, titanium dioxide, zinc oxide, aluminum oxide (alumina), magnesium oxide, antimony oxide, zinc sulfate, and zirconium oxide. These may be used individually or in combination of two or more. To further improve light reflectivity, the white pigment preferably contains at least one selected from the group consisting of titanium dioxide, zinc oxide, alumina, magnesium oxide, antimony oxide, and zirconium oxide, and more preferably contains at least one selected from the group consisting of titanium dioxide, antimony oxide, and zirconium oxide.

[0029] The median particle size of the white pigment may be 0.05 to 10 μm, 0.08 to 8 μm, or 0.1 to 5 μm. A median particle size of 0.05 μm or larger results in better dispersibility, while a median particle size of less than 10 μm results in better light reflectivity of the cured product. In this specification, the median particle size can be determined as the mass-average value D50 (or median diameter) in particle size distribution measurement by laser diffraction.

[0030] (Inorganic hollow particles) The thermosetting resin composition according to this embodiment contains inorganic hollow particles with a central particle size of 1 to 25 μm as an inorganic filler. Inorganic hollow particles are particles that have voids inside. Since inorganic hollow particles refract and reflect incident light at their surface and inner walls, using them in combination with a white pigment can form a cured product with further improved light reflectivity and mechanical properties.

[0031] Examples of inorganic hollow particles include sodium silicate glass, aluminosilicate glass, sodium borosilicate glass, and shirasu (white sand). From the viewpoint of heat resistance and pressure resistance, the outer shell of the inorganic hollow particles is preferably composed of at least one material selected from the group consisting of sodium silicate glass, aluminosilicate glass, sodium borosilicate glass, shirasu, crosslinked styrene resin, and crosslinked acrylic resin, and more preferably composed of at least one material selected from the group consisting of sodium silicate glass, aluminosilicate glass, sodium borosilicate glass, and shirasu.

[0032] When the central particle size of the inorganic hollow particles is 1 μm or larger, it is easier to uniformly disperse the hollow particles when preparing the thermosetting resin composition. The central particle size of the inorganic hollow particles may be 5 μm or larger, or 10 μm or larger. Furthermore, when the central particle size of the inorganic hollow particles is 25 μm or smaller, it is easier to improve the light reflectivity properties of the resulting cured product. The central particle size of the inorganic hollow particles may be 22 μm or smaller.

[0033] To further improve the mechanical properties of the thermosetting resin composition, the thickness of the outer shell of the inorganic hollow particles may be 0.4 to 1.3 μm, 0.45 to 1.2 μm, 0.5 to 1.1 μm, or 0.55 to 1.0 μm.

[0034] To further improve light reflectivity, the bulk density of inorganic hollow particles is 0.20-0.36 g / cm³. 3 , 0.25~0.35 g / cm³ 3 , or 0.26~0.34 g / cm³ 3 It is acceptable. Bulk density is the density calculated by filling a container of a certain volume with inorganic hollow particles and using its internal volume as the volume.

[0035] Due to its excellent balance of light reflectivity and mechanical properties, the true density of inorganic hollow particles is 0.40 to 0.75 g / cm³. 3 , 0.45~0.70 g / cm³ 3 , or 0.50~0.65 g / cm³ 3 This is acceptable. The true density can be measured in accordance with ASTM D2840.

[0036] To improve the strength of the cured product of the thermosetting resin composition, the pressure resistance strength of the inorganic hollow particles may be 100 MPa or higher, 110 MPa or higher, 125 MPa or higher, or 150 MPa or higher at 25°C. To improve the moldability of the thermosetting resin composition, the pressure resistance strength of the inorganic hollow particles may be 500 MPa or lower, 300 MPa or lower, or 200 MPa or lower at 25°C. The pressure resistance strength can be measured in accordance with ASTM D3102.

[0037] From the viewpoint of further improving light reflectivity, the content of inorganic hollow particles according to this embodiment is preferably 10 to 200 parts by mass, more preferably 30 to 180 parts by mass, and even more preferably 60 to 150 parts by mass, per 100 parts by mass of epoxy resin.

[0038] (Inorganic fillers other than inorganic hollow particles) The thermosetting resin composition according to this embodiment may contain inorganic fillers other than inorganic hollow particles from the viewpoint of improving moldability. Examples of inorganic fillers other than inorganic hollow particles include quartz, fumed silica, precipitated silica, anhydrous silicic acid, fused silica, crystalline silica, ultrafine amorphous silica, barium sulfate, magnesium carbonate, barium carbonate, aluminum hydroxide, magnesium hydroxide, potassium titanate, and calcium silicate.

[0039] From the viewpoint of moldability, the inorganic filler may contain fused silica. The central particle size of the fused silica may be 1 to 100 μm, 1 to 50 μm, or 1 to 40 μm, from the viewpoint of improving packing properties with the white pigment.

[0040] (Curing accelerator) The thermosetting resin composition according to this embodiment may contain a curing accelerator to accelerate the curing reaction of the epoxy resin. Examples of curing accelerators include amine compounds, imidazole compounds, organophosphorus compounds, alkali metal compounds, alkaline earth metal compounds, and quaternary ammonium salts. Among these curing accelerators, it is preferable to use amine compounds, imidazole compounds, or organophosphorus compounds. The curing accelerator may be used individually or in combination of two or more.

[0041] Examples of amine compounds include 1,8-diaza-bicyclo[5.4.0]undecene-7, triethylenediamine, and tri-2,4,6-dimethylaminomethylphenol. Examples of imidazole compounds include 2-ethyl-4-methylimidazole. Examples of organophosphorus compounds include triphenylphosphine, tetraphenylphosphonium tetraphenylborate, tetra-n-butylphosphonium-o,o-diethylphosphorodithioate, tetra-n-butylphosphonium-tetrafluoroborate, and tetra-n-butylphosphonium-tetraphenylborate.

[0042] The amount of curing accelerator in the thermosetting resin composition may be 0.01 to 8 parts by mass, 0.1 to 5 parts by mass, or 0.3 to 4 parts by mass per 100 parts by mass of epoxy resin. If the amount of curing accelerator is 0.01 parts by mass or more, a sufficient curing acceleration effect is easily obtained, and if it is 8 parts by mass or less, discoloration of the cured product is easily suppressed.

[0043] (Coupling agent) A coupling agent may be added to the thermosetting resin composition to improve the adhesion between the inorganic filler and the epoxy resin. The coupling agent is not particularly limited, but examples include silane coupling agents and titanate-based coupling agents. Examples of silane coupling agents include epoxysilane compounds, aminosilane compounds, cationic silane compounds, vinylsilane compounds, acrylicsilane compounds, and mercaptosilane compounds. The content of the coupling agent may be 5% by mass or less based on the total amount of the thermosetting resin composition.

[0044] The thermosetting resin composition according to this embodiment may contain additives such as antioxidants, mold release agents, and ion scavengers, as needed.

[0045] The thermosetting resin composition according to this embodiment can be prepared by uniformly dispersing and mixing the various components described above. The means and conditions for preparation are not particularly limited. A general method for preparing the thermosetting resin composition is to knead each component using a kneader, roll, extruder, sculptor, or planetary mixer that combines rotation and revolution. When kneading each component, it is preferable to do so in a molten state from the viewpoint of improving dispersibility.

[0046] The mixing conditions can be appropriately determined depending on the type or amount of each component. For example, mixing at 15-100°C for 5-40 minutes is preferable, and mixing at 20-100°C for 10-30 minutes is more preferable. A mixing temperature of 15°C or higher makes it easier to mix each component and improves dispersibility. A mixing temperature of 100°C or lower can suppress the hardening caused by the increasing molecular weight of the epoxy resin during mixing. A mixing time of 5 minutes or more makes it easier to obtain a sufficient dispersion effect. A mixing time of 40 minutes or less can suppress the hardening caused by the increasing molecular weight of the epoxy resin during mixing.

[0047] The thermosetting resin composition according to this embodiment is useful in a variety of applications requiring high light reflectivity and heat resistance, such as substrate materials for mounting optical semiconductor devices, electrical insulating materials, optical semiconductor encapsulation materials, adhesive materials, paint materials, and epoxy resin molding materials for transfer molding. Examples of using the thermosetting resin composition according to this embodiment as an epoxy resin molding material for transfer molding are described below.

[0048] From the viewpoint of mechanical properties, when the thermosetting resin composition according to this embodiment is transfer-molded under the conditions of a mold temperature of 180°C, a molding pressure of 6.9 MPa, and a curing time of 90 seconds, the flexural strength at 25°C is preferably 70 MPa or more, and more preferably 75 MPa or more. A flexural strength of 70 MPa or more indicates excellent toughness.

[0049] From the viewpoint of improving the brightness of the optoelectronic device, the initial light reflectance at a wavelength of 460 nm of the cured product of the thermosetting resin composition according to this embodiment is preferably 91% or higher, more preferably 92% or higher, and even more preferably 93% or higher. From the viewpoint of improving heat resistance to coloring, the light reflectance at a wavelength of 460 nm after heat treatment of the cured product at 150°C for 168 hours is preferably 85% or higher, more preferably 87% or higher, and even more preferably 88% or higher.

[0050] [Substrate for mounting optoelectronic semiconductor devices] The substrate for mounting optical semiconductor elements in this embodiment has a recess composed of a bottom surface and a wall surface. The bottom surface of the recess is the optical semiconductor element mounting area (optical semiconductor element mounting region), and at least a portion of the wall surface of the recess, i.e., the inner peripheral surface of the recess, is made of a cured product of the light-reflecting thermosetting resin composition of this embodiment.

[0051] Figure 1 is a perspective view showing one embodiment of a substrate for mounting an optical semiconductor device. The substrate 110 for mounting an optical semiconductor device comprises metal wiring 105 (first connection terminal and second connection terminal) with Ni / Ag plating 104, an insulating resin molded body 103' provided between the metal wiring 105 (first connection terminal and second connection terminal), and a reflector 103. It has an optical semiconductor device mounting area (recess) 200 formed from the metal wiring 105 with Ni / Ag plating 104, the insulating resin molded body 103' and the reflector 103. The bottom surface of this recess 200 is composed of the metal wiring 105 with Ni / Ag plating 104 and the insulating resin molded body 103', and the wall surface of the recess 200 is composed of the reflector 103. The reflector 103 and the insulating resin molded body 103' are molded bodies made from cured products of the light-reflecting thermosetting resin composition according to the above embodiment.

[0052] The method for manufacturing a substrate for mounting optical semiconductor devices is not particularly limited, but for example, it can be manufactured by transfer molding using a light-reflective thermosetting resin composition. Figure 2 is a schematic diagram showing one embodiment of the process for manufacturing a substrate for mounting optical semiconductor devices. The substrate for mounting optical semiconductor devices can be manufactured by, for example, forming metal wiring 105 from metal foil by known methods such as punching and etching, and applying Ni / Ag plating 104 by electroplating (Figure 2(a)), then placing the metal wiring 105 in a mold 151 of a predetermined shape, injecting a light-reflective thermosetting resin composition from a resin injection port 150 of the mold 151, and performing transfer molding under predetermined conditions (Figure 2(b)), and finally removing the mold 151 (Figure 2(c)). In this way, an optical semiconductor device mounting region (recess) 200 is formed on the substrate for mounting optical semiconductor devices, surrounded by a reflector 103 made of a cured product of the light-reflective thermosetting resin composition. Furthermore, the bottom surface of the recess 200 is composed of a metal wiring 105 that serves as a first connection terminal and a metal wiring 105 that serves as a second connection terminal, and an insulating resin molded body 103' made of a cured product of a light-reflecting thermosetting resin composition, which is placed between them. The conditions for the above transfer molding are preferably a mold temperature of 170 to 200°C, more preferably 170 to 190°C, a molding pressure of 0.5 to 20 MPa, more preferably 2 to 8 MPa, for 60 to 120 seconds, and an after-cure temperature of 120 to 180°C for 1 to 3 hours.

[0053] [Optical Semiconductor Equipment] The optical semiconductor device according to this embodiment includes the above-mentioned optical semiconductor element mounting substrate and the optical semiconductor element mounted on the optical semiconductor element mounting substrate. A more specific example is an optical semiconductor device comprising the above-mentioned optical semiconductor element mounting substrate, an optical semiconductor element provided in a recess of the optical semiconductor element mounting substrate, and a phosphor-containing sealing resin portion that fills the recess and seals the optical semiconductor element.

[0054] Figure 3 is a perspective view showing one embodiment of a state in which an optical semiconductor element 100 is mounted on an optical semiconductor element mounting substrate 110. As shown in Figure 3, the optical semiconductor element 100 is mounted at a predetermined position in the optical semiconductor element mounting area (recess) 200 of the optical semiconductor element mounting substrate 110 and is electrically connected by metal wiring 105 and bonding wire 102. Figures 4 and 5 are schematic cross-sectional views showing one embodiment of an optoelectronic device. As shown in Figures 4 and 5, the optoelectronic device comprises an optical semiconductor element mounting substrate 110, an optical semiconductor element 100 provided at a predetermined position in the recess 200 of the optical semiconductor element mounting substrate 110, and a sealing resin part consisting of a transparent sealing resin 101 containing a phosphor 106 that fills the recess 200 and seals the optical semiconductor element, and the optical semiconductor element 100 and the metal wiring 105 on which Ni / Ag plating 104 is formed are electrically connected by bonding wire 102 or solder bump 107.

[0055] Figure 6 is also a schematic cross-sectional view showing one embodiment of an optoelectronic semiconductor device. In the optoelectronic semiconductor device shown in Figure 6, an LED element 300 is placed at a predetermined position on a lead 304 on which a reflector 303 is formed, via a die bond material 306. The LED element 300 and the lead 304 are electrically connected by a bonding wire 301, and the LED element 300 is sealed by a transparent sealing resin 302 containing a phosphor 305.

[0056] Preferred embodiments of the present invention have been described above, but the present invention is not limited thereto. For example, the thermosetting resin composition for light reflection of this embodiment can be used as a light-reflective coating agent. A copper-clad laminate, a substrate for mounting an optical semiconductor element, and an optical semiconductor element will be described as embodiments of this embodiment.

[0057] The copper-clad laminate according to this embodiment comprises a light-reflective resin layer formed using the above-described light-reflective thermosetting resin composition, and a copper foil laminated on the light-reflective resin layer.

[0058] Figure 7 is a schematic cross-sectional view showing a preferred embodiment of a copper-clad laminate. As shown in Figure 7, the copper-clad laminate 400 comprises a base material 401, a light-reflective resin layer 402 laminated on the base material 401, and a copper foil 403 laminated on the light-reflective resin layer 402. Here, the light-reflective resin layer 402 is formed using the above-mentioned thermosetting resin composition for light reflection.

[0059] The base material 401 can be any base material used for copper-clad laminates without any particular limitations, but examples include resin laminates such as epoxy resin laminates and substrates for mounting optical semiconductors.

[0060] The copper-clad laminate 400 can be manufactured, for example, by applying the light-reflecting thermosetting resin composition of this embodiment to the surface of a substrate 401, layering copper foil 403 on top, and curing it by heating and pressing to form a light-reflecting resin layer 402 made of the thermosetting resin composition.

[0061] As a method for applying the thermosetting resin composition to the substrate 401, for example, a printing method, die coating method, curtain coating method, spray coating method, roll coating method, etc., can be used. In this case, the thermosetting resin composition may contain a solvent to facilitate application. When a solvent is used, it is preferable to set the total amount of the thermosetting resin composition, based on the blending ratio of each component as described above, to be the amount excluding the solvent.

[0062] The heating and pressurizing conditions are not particularly limited, but it is preferable to heat and pressurize under conditions of 130 to 180°C, 0.5 to 4 MPa, and for 30 to 600 minutes.

[0063] Using the above-described copper-clad laminate, printed circuit boards for optical components such as LED mounting can be manufactured. Note that the copper-clad laminate 400 shown in Figure 7 has a light-reflective resin layer 402 and copper foil 403 laminated on one side of a base material 401. However, the copper-clad laminate may also have the light-reflective resin layer 402 and copper foil 403 laminated on both sides of the base material 401. Furthermore, the copper-clad laminate may consist only of the light-reflective resin layer 402 and copper foil 403 without using the base material 401. In this case, the light-reflective resin layer 402 will serve as the base material. In this case, for example, the light-reflective resin layer 402 can be made by impregnating glass cloth or the like with this thermosetting resin composition and curing it.

[0064] Figure 8 is a schematic cross-sectional view showing an example of an optoelectronic device fabricated using a copper-clad laminate. As shown in Figure 8, the optoelectronic device 500 is a surface-mount type light-emitting diode comprising an optoelectronic element 410 and a transparent sealing resin 404 provided to seal the optoelectronic element 410. In the optoelectronic device 500, the optoelectronic element 410 is bonded to the copper foil 403 via an adhesive layer 408 and is electrically connected to the copper foil 403 by bonding wires 409.

[0065] Another embodiment of the substrate for mounting optical semiconductor elements is a substrate for mounting optical semiconductor elements that includes a light-reflective resin layer formed between a plurality of conductive members (connection terminals) on the substrate using the above-mentioned light-reflective thermosetting resin composition. Another embodiment of the optical semiconductor device is one in which an optical semiconductor element is mounted on the above-mentioned substrate for mounting optical semiconductor elements.

[0066] Figure 9 is a schematic cross-sectional view showing a preferred embodiment of an optoelectronic device. As shown in Figure 9, the optoelectronic device 600 is a surface-mount type light-emitting diode, comprising a substrate 601, a plurality of conductive members 602 formed on the surface of the substrate 601, and a light-reflective resin layer 603 made of the above-mentioned light-reflective thermosetting resin composition formed between the plurality of conductive members (connection terminals) 602, on which an optoelectronic device 610 is mounted, and a transparent sealing resin 604 is provided so as to seal the optoelectronic device 610. In the optoelectronic device 600, the optoelectronic device 610 is bonded to the conductive members 602 via an adhesive layer 608 and is electrically connected to the conductive members 602 by bonding wires 609.

[0067] The substrate 601 can be any substrate used for mounting optical semiconductor devices without any particular limitations, but examples include resin laminates such as epoxy resin laminates.

[0068] The conductor member 602 functions as a connecting terminal and can be formed by known methods, such as photoetching copper foil.

[0069] A substrate for mounting optical semiconductor elements can be manufactured by applying the above-mentioned light-reflecting thermosetting resin composition between a plurality of conductive members 602 on a base material 601, and then heating and curing it to form a light-reflecting resin layer 603 made of the light-reflecting thermosetting resin composition.

[0070] As a method for applying the light-reflective thermosetting resin composition to the substrate 601, for example, a printing method, die coating method, curtain coating method, spray coating method, roll coating method, etc., can be used. In this case, the light-reflective thermosetting resin composition may contain a solvent to facilitate application. When a solvent is used, it is preferable to set the total amount of the resin composition excluding the solvent, based on the blending ratio of each component as described above.

[0071] The heating conditions for heat-curing a coating film of a light-reflective thermosetting resin composition are not particularly limited, but for example, heating may be carried out at 130 to 180°C for 30 to 600 minutes.

[0072] Subsequently, any excess resin components adhering to the surface of the conductor member 602 are removed by buffing or the like to expose the circuit made up of the conductor member 602, thus creating a substrate for mounting optical semiconductor elements. In addition, to ensure adhesion between the light-reflective resin layer 603 and the conductor member 602, the conductor member 602 may be subjected to a roughening treatment such as oxidation-reduction treatment or CZ treatment (manufactured by MEC Corporation).

[0073] Although preferred embodiments of the present invention have been described above, the present invention is not limited thereto. [Examples]

[0074] The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

[0075] [Preparation of thermosetting resin compositions for light reflection] The following components were prepared to create the thermosetting resin compositions of the examples and comparative examples.

[0076] (Epoxy resin) Product name "TEPIC-S" manufactured by Nissan Chemical Industries, Ltd. (trisglycidyl isocyanurate, epoxy equivalent: 100) (Hardening agent) Tetracarboxylic acid dianhydride of formula (1) (Rx: cyclohexane ring, melting point: 40°C) Product name "Ricacid HH" (hexahydrophthalic anhydride) manufactured by Shin Nippon Rika Co., Ltd. Product name "Licacid TH" (1,2,3,6-tetrahydrophthalic anhydride) manufactured by Shin Nippon Rika Co., Ltd. (Curing accelerator) Product name "PX-4PB" (tetrabutylphosphonium tetraphenyl borate) manufactured by Nippon Chemical Industrial Co., Ltd. (Coupling agent) Epoxysilane compound (3-glycidoxypropyltrimethoxysilane)

[0077] (Release agent) Product name "ZNST" (zinc stearate) manufactured by NOF Corporation (Additive) Product name "ADEKA STAB AO-60" (hindered phenol antioxidant) manufactured by ADEKA Corporation Product name "ADEKA STAB PEP-36A" (phosphite antioxidant) manufactured by ADEKA Corporation Product name "DBL-C32" (silicone additive) manufactured by Gelest

[0078] (Inorganic hollow particles) Product name "iM16K" (average particle size: 20 μm, shell layer thickness: 0.66 μm, bulk density: 0.27 g / cm 3 , pressure resistance: 110 MPa) manufactured by 3M Japan Limited Product name "iM30K" (average particle size: 18 μm, shell layer thickness: 0.61 μm, bulk density: 0.33 g / cm 3 , pressure resistance: 186 MPa) manufactured by 3M Japan Limited Product name "S60HS" (average particle size: 30 μm, shell layer thickness: 1.46 μm, bulk density: 0.38 g / cm 3 , pressure resistance: 124 MPa) manufactured by 3M Japan Limited (Silica) Product name "FP-950" (fused silica) manufactured by Denka Co., Ltd. Product name "SO-25R" (fused silica) manufactured by Admatechs Co., Ltd. Product name "Silohobic 702" (hydrophobic fine powder silica) manufactured by Fuji Silysia Chemical Ltd. (White pigment) Titanium oxide (average particle size 0.2 μm)

[0079] According to the mixing ratios (parts by mass) shown in Table 1, each component was mixed, and after thoroughly kneading with a mixer, it was melt-kneaded at 40°C for 15 minutes with a mixing roll to obtain a kneaded product. The kneaded product was cooled and pulverized to prepare the thermosetting resin compositions of the examples and comparative examples, respectively.

[0080] [evaluation] (Bending strength) A thermosetting resin composition was prepared by transfer molding under the following conditions: mold temperature 180°C, molding pressure 6.9 MPa, and curing time 90 seconds, resulting in a 10 mm × 70 mm × 3 mm test specimen. The bending strength of the test specimen was measured at 25°C in accordance with JIS K 6911 using a bending tester (product name "Tensilon" from A&D Co., Ltd.).

[0081] (light reflectance) A thermosetting resin composition was transfer-molded under the conditions of a mold temperature of 180°C, a molding pressure of 6.9 MPa, and a curing time of 90 seconds, and then post-cured at 150°C for 2 hours to prepare a 3.0 mm thick specimen. The light reflectance of the specimen at a wavelength of 460 nm was measured using an integrating sphere spectrophotometer V-750 (manufactured by JASCO Corporation).

[0082] [Table 1]

[0083] Table 1 confirms that the thermosetting resin compositions for light reflection in the examples can form cured products (molded articles) with an excellent balance of mechanical properties and light reflectivity. [Explanation of Symbols]

[0084] 100…Optical semiconductor element, 101…Sealing resin, 102…Bonding wire, 103…Reflector, 103'…Insulating resin molded body, 104…Ni / Ag plating, 105…Metal wiring, 106…Phosphor, 107…Solder bump, 110…Substrate for mounting optical semiconductor element, 150…Resin injection port, 151…Mold, 200…Optical semiconductor element mounting area, 300…LED element, 301…Bonding wire, 302…Sealing resin, 303…Reflector -, 304...lead, 305...phosphor, 306...die bond material, 400...copper-clad laminate, 401...substrate, 402...light-reflective resin layer, 403...copper foil, 404...encapsulating resin, 408...adhesive layer, 409...bonding wire, 410...optoelectronic semiconductor device, 500, 600...optoelectronic device, 601...substrate, 602...conductor material, 603...light-reflective resin layer, 604...encapsulating resin, 608...adhesive layer, 609...bonding wire, 610...optoelectronic semiconductor device.

Claims

1. It contains epoxy resin (excluding compounds represented by the following formula), a curing agent, an inorganic filler, and a white pigment. 【Chemistry 1】 (In the formula, R1 represents a hydrogen atom or a methyl group, R2 represents a divalent organic group, and R3 to R10 each independently represent a hydrogen atom, a substituent, or a molecular chain containing an epoxy group.) The curing agent comprises a tetracarboxylic dianhydride represented by the following formula (1), 【Chemistry 2】 (In formula (1), Rx represents a divalent organic group, and n represents an integer from 1 to 10.) The inorganic filler comprises inorganic hollow particles with a central particle size of 1 to 22 μm. The amount of inorganic hollow particles is 10 to 180 parts by mass per 100 parts by mass of epoxy resin. A thermosetting resin composition for light reflection, wherein the white pigment comprises at least one selected from the group consisting of titanium dioxide, zinc oxide, alumina, magnesium oxide, antimony oxide, and zirconium oxide.

2. The bulk density of the inorganic hollow particles is 0.20 to 0.36 g / cm³. ３ The light-reflecting thermosetting resin composition according to claim 1.

3. The light-reflecting thermosetting resin composition according to claim 1 or 2, wherein the thickness of the outer shell of the inorganic hollow particles is 0.4 to 1.3 μm.

4. The light-reflecting thermosetting resin composition according to any one of claims 1 to 3, wherein the pressure resistance strength of the inorganic hollow particles is 100 MPa or more at 25°C.

5. A substrate for mounting an optical semiconductor device, comprising a cured product of a light-reflecting thermosetting resin composition according to any one of claims 1 to 4.

6. It has a recess consisting of a bottom surface and a wall surface, and the bottom surface of the recess is a mounting area for an optical semiconductor element. A substrate for mounting an optical semiconductor device, wherein at least a portion of the wall surface of the recess is made of a cured product of the light-reflecting thermosetting resin composition described in any one of claims 1 to 4.

7. The device comprises a circuit board and a first connection terminal and a second connection terminal provided on the circuit board. A substrate for mounting an optical semiconductor element, having a cured product of the light-reflecting thermosetting resin composition described in any one of claims 1 to 4 between the first connection terminal and the second connection terminal.

8. An optoelectronic device comprising a substrate for mounting an optoelectronic semiconductor element according to any one of claims 5 to 7, and an optoelectronic semiconductor element mounted on the substrate for mounting the optoelectronic semiconductor element.

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