Abstract: The purpose of the present invention is to safely synthesize high purity tungsten pentachloride at a higher yield and at a higher purity than in prior art. This method for producing tungsten pentachloride includes: a step of mixing a reducing agent selected from the group consisting of Bi, Hg, Sb, Ti, Al, P, and As with tungsten hexachloride uniformly in an inert atmosphere with a molar ratio of the tungsten hexachloride to the reducing agent being 2.8:1.0 to 3.2:1.0 to obtain a mixture; a step of heating the mixture of the reducing agent and the tungsten hexachloride to 80 to 210° C. at 13 Pa or lower and reducing the same; a step of heating the reduced product of the mixture of the reducing agent and the tungsten hexachloride to 120 to 290° C. at 66 Pa or lower and vacuum distilling the same to remove impurities; and a step of heating the reduced product from which impurities have been removed by the vacuum distillation to 140 to 350° C.

Abstract: A copper heat dissipation material having a satisfactory heat dissipation performance is provided. The copper heat dissipation material has an alloy layer containing at least one metal selected from Cu, Co, Ni, W, P, Zn, Cr, Fe, Sn and Mo on one or both surfaces, in which surface roughness Sz of the one or both surfaces, measured by a laser microscope using laser light of 405 nm in wavelength, is 5 ?m or more.

Abstract: The purpose of the present invention is to safely synthesize high purity tungsten pentachloride at a higher yield and at a higher purity than in prior art. This method for producing tungsten pentachloride includes: a step of mixing a reducing agent selected from the group consisting of Bi, Hg, Sb, Ti, Al, P, and As with tungsten hexachloride uniformly in an inert atmosphere with a molar ratio of the tungsten hexachloride to the reducing agent being 2.8:1.0 to 3.2:1.0 to obtain a mixture; a step of heating the mixture of the reducing agent and the tungsten hexachloride to 80 to 210° C. at 13 Pa or lower and reducing the same; a step of heating the reduced product of the mixture of the reducing agent and the tungsten hexachloride to 120 to 290° C. at 66 Pa or lower and vacuum distilling the same to remove impurities; and a step of heating the reduced product from which impurities have been removed by the vacuum distillation to 140 to 350° C.

Abstract: A copper heat dissipation material having a satisfactory heat dissipation performance is provided. The copper heat dissipation material has an alloy layer containing at least one metal selected from Cu, Co, Ni, W, P, Zn, Cr, Fe, Sn and Mo on one or both surfaces, in which surface roughness Sz of the one or both surfaces, measured by a laser microscope using laser light of 405 nm in wavelength, is 5 ?m or more.

Abstract: A copper heat dissipation material having a satisfactory heat dissipation performance is provided. The copper heat dissipation material has an alloy layer containing at least one metal selected from Cu, Co, Ni, W, P, Zn, Cr, Fe, Sn and Mo on one or both surfaces, in which surface roughness Sz of the one or both surfaces, measured by a laser microscope using laser light of 405 nm in wavelength, is 5 ?m or more.

Abstract: A copper heat dissipation material having a satisfactory heat dissipation performance is provided. The copper heat dissipation material has an alloy layer containing at least one metal selected from Cu, Co, Ni, W, P, Zn, Cr, Fe, Sn and Mo on one or both surfaces, in which surface roughness Sz of the one or both surfaces, measured by a laser microscope using laser light of 405 nm in wavelength, is 5 ?m or more.

Abstract: Disclosed is a technology of manufacturing, at low cost, an epitaxial crystal substrate provided with a high-quality and uniform epitaxial layer, said technology being useful in the case of growing the epitaxial layer composed of a semiconductor having a lattice constant different from that of the substrate. The substrate, which is composed of a first compound semiconductor, and which has a step-terrace structure on the surface, is used, and on the surface of the substrate, a composition modulation layer composed of a second compound semiconductor is grown by step-flow, while changing the composition in the same terrace. Then, the epitaxial crystal substrate is manufactured by growing, on the composition modulation layer, the epitaxial layer composed of the third compound semiconductor having the lattice constant different from that of the first compound semiconductor.

Abstract: Disclosed is a technology of manufacturing, at low cost, an epitaxial crystal substrate provided with a high-quality and uniform epitaxial layer, said technology being useful in the case of growing the epitaxial layer composed of a semiconductor having a lattice constant different from that of the substrate. The substrate, which is composed of a first compound semiconductor, and which has a step-terrace structure on the surface, is used, and on the surface of the substrate, a composition modulation layer composed of a second compound semiconductor is grown by step-flow, while changing the composition in the same terrace. Then, the epitaxial crystal substrate is manufactured by growing, on the composition modulation layer, the epitaxial layer composed of the third compound semiconductor having the lattice constant different from that of the first compound semiconductor.

Abstract: Disclosed is a method of producing a semiconductor device, able to form a source/drain of a Schottky junction (FET) with simple steps and able to improve the device characteristics. A gate is formed on an element region defined in a silicon substrate layer by element isolation regions (first step), the silicon substrate is etched by self-alignment using the gate and the element isolation regions as masks (second step), and an insulating film is formed on the side surfaces of the gate (third step). Then, a metal film acting as the source/drain is selectively formed on the etching region of the silicon substrate by electroless plating (fourth step).