Abstract: A heat sink substrate has a composite structure including a three-dimensional network structure of SiC ceramic having pores infiltrated with Si, and has a thermal conductivity of not less than 150 W/m·K and an oxygen content of not greater than 7 ppm. The heat sink substrate is easily allowed to have an increased surface area. Further, the heat sink substrate has a higher thermal conductivity and a coefficient thermal expansion close to that of the SiC. Therefore, the heat sink substrate is superior in the efficiency of heat conduction from a semiconductor device. The heat sink substrate is produced by infiltrating a thermally melted Si into the pores of the three-dimensional network structure in a non-oxidative atmosphere in the presence of an oxygen absorber.

Abstract: A heat sink substrate has a composite structure including a three-dimensional network structure of SiC ceramic having pores infiltrated with Si, and has a thermal conductivity of not less than 150 W/m·K and an oxygen content of not greater than 7 ppm. The heat sink substrate is easily allowed to have an increased surface area. Further, the heat sink substrate has a higher thermal conductivity and a coefficient thermal expansion close to that of the SiC. Therefore, the heat sink substrate is superior in the efficiency of heat conduction from a semiconductor device. The heat sink substrate is produced by infiltrating a thermally melted Si into the pores of the three-dimensional network structure in a non-oxidative atmosphere in the presence of an oxygen absorber.

Abstract: The object of the present invention is to provide: a novel stiffener with superior cosmetic appearance and adhesive qualities and that is easy to make; a method for making the same; and a semiconductor device using this stiffener. A stiffener 1 is punched from a plate material 10. The outer perimeter end surface thereof is formed with shear surfaces and fracture surfaces created by the punching operations and abraded surfaces extending along the thickness axis of the plate created by the abrasion of projections on the fracture surfaces. In the method for making the stiffener, the stiffener is formed by being punched from the plate material 10. Then, it is re-fitted to the punched hole 10a of the plate material 10 and removed from the plate material 10 once more. The semiconductor device is reinforced using this stiffener 1.

Abstract: A heat-dissipating substrate is made of a composite material comprising a first composition primarily composed of aluminum and a second composition primarily composed of silicon carbide and/or silicon The heat-dissipating substrate has a recess in one of its main faces. The main faces have fine unevenness, and the maximum amplitude of the fine unevenness in the depth direction of a main face is smaller than the maximum length in the depth direction of composite particles comprising the first composition and the second composition or particles of the second composition, the particles being exposed at the surface of the main face.

Abstract: A heat-dissipating substrate is made of a composite material comprising a first composition primarily composed of aluminum and a second composition primarily composed of silicon carbide and/or silicon The heat-dissipating substrate has a recess in one of its main faces. The main faces have fine unevenness, and the maximum amplitude of the fine unevenness in the depth direction of a main face is smaller than the maximum length in the depth direction of composite particles comprising the first composition and the second composition or particles of the second composition, the particles being exposed at the surface of the main face.