Abstract: A boron nitride/resin composite circuit board having high heat dissipation characteristics and high reliability is provided. A boron nitride/resin composite circuit board, including: a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body including 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 ?m, and 70 to 15 volume % of a resin; and a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper or aluminum, wherein: a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.

Abstract: There is provided a method for producing hexagonal boron nitride, including a heating step of heating a mixture containing boron carbide and an alkaline earth metal compound under an ammonia atmosphere at 1300-1500° C. to obtain a product containing hexagonal boron nitride, wherein a molar ratio of the boron carbide to the alkaline earth metal compound in the mixture is 0.5-2.0.

Abstract: A boron nitride/resin composite circuit board having high heat dissipation characteristics and high relyability is provided. A boron nitride/resin composite circuit board, including: a plate-shaped resin-impregnated boron nitride sintered body having a plate thickness of 0.2 to 1.5 mm, the plate-shaped resin-impregnated boron nitride sintered body including 30 to 85 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally, the boron nitride particles having an average long diameter of 5 to 50 ?m, and 70 to 15 volume % of a resin; and a metal circuit adhered onto both principal planes of the plate-shaped resin-impregnated boron nitride sintered body, the metal circuit being copper or aluminum, wherein: a ratio of a linear thermal expansion coefficient in a plane direction of the resin-impregnated boron nitride sintered body at 40 to 150° C. (CTE1) and a linear thermal expansion coefficient of the metal circuit at 40 to 150° C. (CTE2) (CTE1/CTE2) is 0.5 to 2.0.

Abstract: A substrate for an LED light emitting element having a small difference of linear thermal expansion coefficient with the III-V semiconductor crystal constituting an LED, having an excellent thermal conductivity, and suitable for high output LEDs. A porous body comprises one or more materials selected from silicon carbide, aluminum nitride, silicon nitride, diamond, graphite, yttrium oxide, and magnesium oxide and has a porosity that is 10 to 50 volume % and a three-point bending strength that is 50 MPa or more. The porous body is infiltrated, by means of liquid metal forging, with aluminum alloy or pure aluminum at an infiltration pressure of 30 MPa or more, cut and/or ground to a thickness of 0.05 to 0.5 mm and to a surface roughness (Ra) of 0.01 to 0.5 ?m, then is formed with a metal layer comprising one or more elements selected from Ni, Co, Pd, Cu, Ag, Au, Pt and Sn on its surface to a thickness of 0.5 to 15 ?m, so as to thereby produce the composite substrate for the LED light emitting element.

Abstract: A resin-impregnated boron nitride sintered body having superior thermal conductivity and superior strength, and a resin-impregnated boron nitride sintered body having superior conductivity and small anisotropy of thermal conductivity are provided. A resin-impregnated boron nitride sintered body, including: 30 to 90 volume % of a boron nitride sintered body having boron nitride particles bonded three-dimensionally; and 10 to 70 volume % of a resin; wherein the boron nitride sintered body has a porosity of 10 to 70%; the boron nitride particles of the boron nitride sintered body has an average long diameter of 10 ?m or more; the boron nitride sintered body has a graphitization index by powder X-ray diffractometry is 4.0 or less; and an orientation degree of the boron nitride particles of the boron nitride sintered body by I.O.P is 0.01 to 0.

Abstract: Disclosed is a clad material for an LED light-emitting element holding substrate in which a plurality of layers composed of different materials are stacked and bonded via a metal layer to a III-V group semiconductor crystal surface, the linear expansion coefficient being 14×10?6/K or less and the thermal conductivity at a temperature of 25° C. being 200 W/mK or greater. The clad material is composed of three alternately stacked layers: two copper layers and a molybdenum layer, the molybdenum layer being 10 to 60 vol % and the difference in thickness between the copper layers being 5% or less; or a clad material composed of three copper layers alternately stacked with molybdenum layers to make five layers, the molybdenum layers being 20 to 70 vol % and the difference in thickness between the top and bottom two copper layers and the molybdenum layers being 5% or less.

Abstract: Disclosed is an aluminum-diamond composite having both high thermal conductivity and thermal expansion coefficient close to those of semiconductor elements, which is improved in platability in the surface and surface roughness so that the composite becomes suitable for use as a heat sink of a semiconductor element of the like. Specifically disclosed is a plate-like aluminum-diamond composite containing diamond particles and a metal mainly composed of aluminum. The aluminum-diamond composite is composed of a composite part and surface layers formed on both sides of the composite part, and the surface layers are composed of a material containing a metal mainly composed of aluminum. The diamond particle content is 40-70% by volume of the entire aluminum-diamond composite.

Abstract: Disclosed is a clad material for an LED light-emitting element holding substrate in which a plurality of layers composed of different materials are stacked and bonded via a metal layer to a III-V group semiconductor crystal surface, the linear expansion coefficient being 14×10?6/K or less and the thermal conductivity at a temperature of 25° C. being 200 W/mK or greater. The clad material is composed of three alternately stacked layers: two copper layers and a molybdenum layer, the molybdenum layer being 10 to 60 vol % and the difference in thickness between the copper layers being 5% or less; or a clad material composed of three copper layers alternately stacked with molybdenum layers to make five layers, the molybdenum layers being 20 to 70 vol % and the difference in thickness between the top and bottom two copper layers and the molybdenum layers being 5% or less.

Abstract: Provided is a wafer for LED mounting having a small difference in thermal expansion coefficient from an LED and having excellent heat conductivity, a method for manufacturing the wafer for LED mounting, and an LED-mounted structure manufactured by using the wafer for LED mounting. The wafer for LED mounting (6) is constituted of a metal infiltrated ceramic composite (61) and a protective layer (62) that is formed therearound. The metal infiltrated ceramic composite (61) preferably has a thin metal layer (63) on a surface thereof. The method for manufacturing the wafer is characterized by comprising filling at least one selected from the group consisted of porous ceramic bodies, ceramic powder compacts and ceramic powders into a tubular body made of metal or ceramic, then impregnating a metal into the void of at least one selected from the group consisted of porous ceramic bodies, ceramic powder compacts and ceramic powders, and thereafter performing a process.

Abstract: A process for producing a substrate, which comprises processing an aluminum/graphite composite into plates having a thickness of 0.5-3 mm using a multi-wire saw under the following conditions (1) to (4): (1) the wires have abrasive grains bonded thereto which are one or more substances selected from diamond, C—BN, silicon carbide, and alumina and have an average particle diameter of 10-100 ?m; (2) the wires have a diameter of 0.1-0.3 mm; (3) the wires are run at a rate of 100-700 m/min; and (4) the composite is cut at a rate of 0.1-2 mm/min. The aluminum/graphite composite has a surface roughness (Ra) of 0.1-3 ?m, a thermal conductivity at 25° C. of 150-300 W/mK, a ratio of the maximum to the minimum value of thermal conductivity in three perpendicular directions of 1-1.3, a coefficient of thermal expansion at 25-150° C. of 4×106 to 7.5×10?6/K, a ratio of the maximum to the minimum value of coefficient of thermal expansion in three perpendicular directions of 1-1.

Abstract: Disclosed is a heat dissipating component for a semiconductor element, having a tabular body 0.4-6 mm in thickness containing 40-70 volume % of diamond particles, with the balance comprising metal of which the principal component is aluminum, and coated on both surfaces by a coating layer comprising metal of which the principal component is aluminum, or an aluminum-ceramic based composite material, to form an aluminum-diamond based composite body. On at least the two major surfaces thereof are formed, in order from the major surface side, (1) an amorphous Ni alloy layer 0.1-1 ?m in film thickness, (2) an Ni layer 1-5 ?m in film thickness, and (3) an Au layer 0.05-4 ?m in film thickness, the ratio of the Ni alloy layer and the Ni layer (Ni alloy layer thickness/Ni layer thickness) being 0.3 or less.

Abstract: Provided is a highly reliable LED package with significantly improved heat radiating properties, manufacturing method of the LED package, and an LED chip assembly used in the LED package. The LED package is characterized in that the LED chip assembly (10) is bonded to a circuit board (11) created by forming metal circuitry (3) on a metal substrate (5) with an insulation layer (4) therebetween, whereas an LED chip (1) of the LED chip assembly and the metal circuitry (3) of the circuit board are connected via an electrical connection member (9), and at least the LED chip assembly and the electrical connection member are encapsulated with resin encapsulant (8) including fluorescent material.

Abstract: A process for the production of an aluminum-diamond composite, characterized by comprising the step of preparing a diamond powder having a specific diameter, the step of adding a colloidal silica to the diamond powder to form a slurry, the step of subjecting the slurry to press forming or slip casting to produce a compact of the diamond particles, the step of firing the compact either in air or in a nitrogen atmosphere to form a porous diamond preform, the step of heating the porous diamond preform, the step of heating an aluminum alloy to a temperature equal to or above the melting point of the alloy and impregnating the molten alloy into the porous diamond preform to make a flat plate-like aluminum-diamond composite wherein both surfaces are covered with surface layers containing an aluminum-base metal, and the step of working the aluminum-diamond composite into an aluminum-diamond composite.

Abstract: Provided is a wafer for LED mounting having a small difference in thermal expansion coefficient from an LED and having excellent heat conductivity, a method for manufacturing the wafer for LED mounting, and an LED-mounted structure manufactured by using the wafer for LED mounting. The wafer for LED mounting (6) is constituted of a metal infiltrated ceramic composite (61) and a protective layer (62) that is formed therearound. The metal infiltrated ceramic composite (61) preferably has a thin metal layer (63) on a surface thereof. The method for manufacturing the wafer is characterized by comprising filling at least one selected from the group consisted of porous ceramic bodies, ceramic powder compacts and ceramic powders into a tubular body made of metal or ceramic, then impregnating a metal into the void of at least one selected from the group consisted of porous ceramic bodies, ceramic powder compacts and ceramic powders, and thereafter performing a process.

Abstract: Provided is a highly reliable LED package with significantly improved heat radiating properties, manufacturing method of the LED package, and an LED chip assembly used in the LED package. The LED package is characterized in that the LED chip assembly (10) is bonded to a circuit board (11) created by forming metal circuitry (3) on a metal substrate (5) with an insulation layer (4) therebetween, whereas an LED chip (1) of the LED chip assembly and the metal circuitry (3) of the circuit board are connected via an electrical connection member (9), and at least the LED chip assembly and the electrical connection member are encapsulated with resin encapsulant (8) including fluorescent material.

Abstract: A process for producing a substrate, which comprises processing an aluminum/graphite composite into plates having a thickness of 0.5-3 mm using a multi-wire saw under the following conditions (1) to (4): (1) the wires have abrasive grains bonded thereto which are one or more substances selected from diamond, C—BN, silicon carbide, and alumina and have an average particle diameter of 10-100 ?m; (2) the wires have a diameter of 0.1-0.3 mm; (3) the wires are run at a rate of 100-700 m/min; and (4) the composite is cut at a rate of 0.1-2 mm/min. The aluminum/graphite composite has a surface roughness (Ra) of 0.1-3 ?m, a thermal conductivity at 25° C. of 150-300 W/mK, a ratio of the maximum to the minimum value of thermal conductivity in three perpendicular directions of 1-1.3, a coefficient of thermal expansion at 25-150° C. of 4×106 to 7.5×10?6/K, a ratio of the maximum to the minimum value of coefficient of thermal expansion in three perpendicular directions of 1-1.

Abstract: A substrate for an LED light emitting element having a small difference of linear thermal expansion coefficient with the III-V semiconductor crystal constituting an LED, having an excellent thermal conductivity, and suitable for high output LEDs. A porous body comprises one or more materials selected from silicon carbide, aluminum nitride, silicon nitride, diamond, graphite, yttrium oxide, and magnesium oxide and has a porosity that is 10 to 50 volume % and a three-point bending strength that is 50 MPa or more. The porous body is infiltrated, by means of liquid metal forging, with aluminum alloy or pure aluminum at an infiltration pressure of 30 MPa or more, cut and/or ground to a thickness of 0.05 to 0.5 mm and to a surface roughness (Ra) of 0.01 to 0.5 ?m, then is formed with a metal layer comprising one or more elements selected from Ni, Co, Pd, Cu, Ag, Au, Pt and Sn on its surface to a thickness of 0.5 to 15 ?m, so as to thereby produce the composite substrate for the LED light emitting element.

Abstract: An aluminum-silicon carbide composite suitable for a base plate for power module, having an aluminum-silicon carbide composite, with a front and a rear surface plane, that is a flat plate-shaped silicon carbide porous body impregnated with a metal mainly containing aluminum, and an aluminum layer made of a metal mainly containing aluminum formed only on the front surface plane, wherein the rear surface plane of the composite is exposed to the outside, and the shape of the exposed aluminum-silicon carbide composite is rectangular, optionally having peripheral portions encompassing holes removed. Plating is imparted to the composite by providing an aluminum layer on the rear surface plane. Flatness of the composite is improved by grinding its rear surface so that the composite is exposed to the outside. Warpage after grinding the rear surface, is controlled by controlling the thickness of the aluminum layer.

Abstract: A process for the production of an aluminum-diamond composite, characterized by comprising the step of preparing a diamond powder having a specific diameter, the step of adding a colloidal silica to the diamond powder to form a slurry, the step of subjecting the slurry to press forming or slip casting to produce a compact of the diamond particles, the step of firing the compact either in air or in a nitrogen atmosphere to form a porous diamond preform, the step of heating the porous diamond preform, the step of heating an aluminum alloy to a temperature equal to or above the melting point of the alloy and impregnating the molten alloy into the porous diamond preform to make a flat plate-like aluminum-diamond composite wherein both surfaces are covered with surface layers containing an aluminum-base metal, and the step of working the aluminum-diamond composite into an aluminum-diamond composite.

Abstract: A base plate for power module, comprising an aluminum-silicon carbide composite and aluminum layers made of a metal containing aluminum as the main component formed on respective principal planes of the aluminum-silicon carbide composite, wherein the aluminum-silicon carbide composite is produced by forming or fabricating a flat plate-shaped silicon carbide porous body to have a thickness difference of at most 100 ?m in the entire porous body and piling such porous bodies as they are each sandwiched between mold-releasing plates so that the fastening torque in the plane direction becomes from 1 to 20 Nm, and infiltrating a metal containing aluminum as the main component into the silicon carbide porous bodies, wherein the aluminum layers each has an average thickness of from 10 to 150 ?m, the difference between the maximum thickness and the minimum thickness of the aluminum layer in each principal plane is at most 80 ?m, and the difference between average thicknesses of the aluminum layers on the respective pr