Abstract: The invention provides a method for manufacturing the silicon carbide single crystal wafer capable of improving the utilization ratio of the bulk silicon carbide single crystal, capable of improving characteristics of the element and capable of improving cleavability, and the silicon carbide single crystal wafer obtained by the manufacturing method. An ?(hexagonal)-silicon carbide single crystal wafer which has a flat homoepitaxial growth surface with a surface roughness of 2 nm or less and which has an off-angle from the (0001)c plane of 0.4° or less.

Abstract: There is provided a key switch structure including: a plate shaped key top; a link mechanism supporting the key top such that the key top can be depressed; a membrane sheet comprising a contact point portion; a back plate supporting the link mechanism and adhered to the membrane sheet; a plurality of holder members insert molded onto the back plate and supporting the link mechanism; and a resilient member provided between the key top and the membrane sheet, the resilient member being compressed by depressing of the key top and pressing the contact point portion to make a continuity.

Abstract: A link structure can include an outside link member and an inside link member. Shaft holes can be formed in respective inner lateral sides of the outside link member and face each other across a first opening portion. First stopper members can be arranged on the respective inner lateral sides, and each have a first inclined face and a first stopper surface. The outside link member can be elastically deformable based on a pressure applied to the first inclined surfaces that increases a distance between the shaft holes. The inside link member can include a second opening portion, link rotational shafts that are disposed in the shaft holes, and second stopper members each having a second inclined surface and a second stopper surface. The inside link member can be elastically deformable based on a pressure applied to the second inclined surfaces that decreases a distance between the link rotational shafts.

Abstract: A link structure can include an outside link member and an inside link member. Shaft holes can be formed in respective inner lateral sides of the outside link member and face each other across a first opening portion. First stopper members can be arranged on the respective inner lateral sides, and each have a first inclined face and a first stopper surface. The outside link member can be elastically deformable based on a pressure applied to the first inclined surfaces that increases a distance between the shaft holes. The inside link member can include a second opening portion, link rotational shafts that are disposed in the shaft holes, and second stopper members each having a second inclined surface and a second stopper surface. The inside link member can be elastically deformable based on a pressure applied to the second inclined surfaces that decreases a distance between the link rotational shafts.

Abstract: There is provided a key switch structure including: a plate shaped key top; a link mechanism supporting the key top such that the key top can be depressed; a membrane sheet comprising a contact point portion; a back plate supporting the link mechanism and adhered to the membrane sheet; a plurality of holder members insert molded onto the back plate and supporting the link mechanism; and a resilient member provided between the key top and the membrane sheet, the resilient member being compressed by depressing of the key top and pressing the contact point portion to make a continuity.

Abstract: A process for manufacturing a wafer of a silicon carbide single crystal having: cutting a wafer from an ? (hexagonal)-silicon carbide single crystal so that the off-angle is totally in the range from 0.4 to 2° to a plane obtained in perpendicular to the [0001]c axis of the silicon carbide single crystal; disposing the wafer in a reaction vessel; feeding a silicon source gas and carbon source gas in the reaction vessel; and epitaxially growing the ? (hexagonal) silicon carbide single crystal on the wafer by allowing the silicon source gas and carbon source gas to react.

Abstract: A key switch structure includes a key top, a membrane sheet, a plate member, and a light source. The key top on which an unpainted character portion that is permeable to light is formed. The membrane sheet comprises a contact portion and is permeable to light. The plate member is disposed below the membrane sheet and is permeable to light. The light source is disposed below the plate member. The unpainted character portion of the key top is lighted via the plate member and the membrane sheet by causing the light source to emit light.

Abstract: The invention provides a method for manufacturing the silicon carbide single crystal wafer capable of improving the utilization ratio of the bulk silicon carbide single crystal, capable of improving characteristics of the element and capable of improving cleavability, and the silicon carbide single crystal wafer obtained by the manufacturing method. An ?(hexagonal)-silicon carbide single crystal wafer which has a flat homoepitaxial growth surface with a surface roughness of 2 nm or less and which has an off-angle from the (0001)c plane of 0.4° or less.

Abstract: A process for manufacturing a wafer of a silicon carbide single crystal having: cutting a wafer from an ? (hexagonal)-silicon carbide single crystal so that the off-angle is totally in the range from 0.4 to 2° to a plane obtained in perpendicular to the [0001]c axis of the silicon carbide single crystal; disposing the wafer in a reaction vessel; feeding a silicon source gas and carbon source gas in the reaction vessel; and epitaxially growing the ? (hexagonal) silicon carbide single crystal on the wafer by allowing the silicon source gas and carbon source gas to react.

Abstract: A keyboard apparatus has a base component arranged under key switches. The base component has an embossed portion. A cooling material is filled into the embossed portion. The embossed portion may be formed continuously between the key switches along the length of key rows over substantially the entire length from the left end to the right end of the rows. On the base component, a membrane sheet having contact point portions corresponding to the key switches may be arranged. The membrane sheet may have a heat dissipation hole at a part opposing the embossed portion.

Abstract: A key switch structure includes a key top, a membrane sheet, a plate member, and a light source. The key top on which an unpainted character portion that is permeable to light is formed. The membrane sheet comprises a contact portion and is permeable to light. The plate member is disposed below the membrane sheet and is permeable to light. The light source is disposed below the plate member. The unpainted character portion of the key top is lighted via the plate member and the membrane sheet by causing the light source to emit light.

Abstract: A keyboard apparatus has a base component arranged under key switches. The base component has an embossed portion. A cooling material is filled into the embossed portion. The embossed portion may be formed continuously between the key switches along the length of key rows over substantially the entire length from the left end to the right end of the rows. On the base component, a membrane sheet having contact point portions corresponding to the key switches may be arranged. The membrane sheet may have a heat dissipation hole at a part opposing the embossed portion.