Abstract: An optical device includes an optical unit that is disposed with a closed space interposed between the optical unit and a windshield glass and is configured to acquire information of an outside of a vehicle cabin through the windshield glass, a heating unit that heats the closed space, an opening and closing unit that is disposed in an air flow path between the closed space and a vehicle cabin internal space and controls communication of air between the closed space and the vehicle cabin internal space, and a controller that controls an open and closed state of the opening and closing unit based on either an outside air temperature of a vehicle or a difference in humidity acquired by subtracting a humidity of the vehicle cabin internal space from a humidity of the closed space.

Abstract: A vehicular optical system includes an optical device disposed to acquire information on an environment outside a vehicle cabin, a transparent member disposed on a front surface of the optical device via a predetermined closed space, an anti-fogging sheet disposed in a first region of an inner surface of the transparent member in the closed space, the first region being within an angle of view of the optical device, and a dew condensation portion disposed in a second region of the inner surface of the transparent member in the closed space, the second region being out of the angle of view of the optical device and dew condensation being more likely to occur in the dew condensation portion than in the first region.

Abstract: An optical device includes an optical unit that is disposed with a closed space interposed between the optical unit and a windshield glass and is configured to acquire information of an outside of a vehicle cabin through the windshield glass, a heating unit that heats the closed space, an opening and closing unit that is disposed in an air flow path between the closed space and a vehicle cabin internal space and controls communication of air between the closed space and the vehicle cabin internal space, and a controller that controls an open and closed state of the opening and closing unit based on either an outside air temperature of a vehicle or a difference in humidity acquired by subtracting a humidity of the vehicle cabin internal space from a humidity of the closed space.

Abstract: A vehicular optical system includes an optical device disposed to acquire information on an environment outside a vehicle cabin, a transparent member disposed on a front surface of the optical device via a predetermined closed space, an anti-fogging sheet disposed in a first region of an inner surface of the transparent member in the closed space, the first region being within an angle of view of the optical device, and a dew condensation portion disposed in a second region of the inner surface of the transparent member in the closed space, the second region being out of the angle of view of the optical device and dew condensation being more likely to occur in the dew condensation portion than in the first region.

Abstract: In a silicon carbide semiconductor device, a p-type SiC layer is disposed in a corner of a bottom of a trench. Thus, even if an electric field is applied between a drain and a gate when a MOSFET is turned off, a depletion layer in a pn junction between the p-type SiC layer and an n? type drift layer greatly extends toward the n? type drift layer, and a high voltage caused by an influence of a drain voltage hardly enters a gate insulating film. Hence, an electric field concentration within the gate insulating film can be reduced, and the gate insulating film can be restricted from being broken. In this case, although the p-type SiC layer may be in a floating state, the p-type SiC layer is formed in only the corner of the bottom of the trench. Thus, the deterioration of the switching characteristic is relatively low.

Abstract: In a method for producing an SiC semiconductor device, a p type layer is formed in a trench by epitaxially growing, and is then left only on a bottom portion and ends of the trench by hydrogen etching, thereby to form a p type SiC layer. Thus, the p type SiC layer can be formed without depending on diagonal ion implantation. Since it is not necessary to separately perform the diagonal ion implantation, it is less likely that a production process will be complicated due to transferring into an ion implantation apparatus, and thus manufacturing costs reduce. Since there is no damage due to a defect caused by the ion implantation, it is possible to reduce a drain leakage and to reliably restrict the p type SiC layer from remaining on the side surface of the trench.

Abstract: In a method for producing an SiC semiconductor device, a p type layer is formed in a trench by epitaxially growing, and is then left only on a bottom portion and ends of the trench by hydrogen etching, thereby to form a p type SiC layer. Thus, the p type SiC layer can be formed without depending on diagonal ion implantation. Since it is not necessary to separately perform the diagonal ion implantation, it is less likely that a production process will be complicated due to transferring into an ion implantation apparatus, and thus manufacturing costs reduce. Since there is no damage due to a defect caused by the ion implantation, it is possible to reduce a drain leakage and to reliably restrict the p type SiC layer from remaining on the side surface of the trench.

Abstract: In a method for producing an SiC semiconductor device, a p type layer is formed in a trench by epitaxially growing, and is then left only on a bottom portion and ends of the trench by hydrogen etching, thereby to form a p type SiC layer. Thus, the p type SiC layer can be formed without depending on diagonal ion implantation. Since it is not necessary to separately perform the diagonal ion implantation, it is less likely that a production process will be complicated due to transferring into an ion implantation apparatus, and thus manufacturing costs reduce. Since there is no damage due to a defect caused by the ion implantation, it is possible to reduce a drain leakage and to reliably restrict the p type SiC layer from remaining on the side surface of the trench.

Abstract: In a method for producing an SiC semiconductor device, a p type layer is formed in a trench by epitaxially growing, and is then left only on a bottom portion and ends of the trench by hydrogen etching, thereby to form a p type SiC layer. Thus, the p type SiC layer can be formed without depending on diagonal ion implantation. Since it is not necessary to separately perform the diagonal ion implantation, it is less likely that a production process will be complicated due to transferring into an ion implantation apparatus, and thus manufacturing costs reduce. Since there is no damage due to a defect caused by the ion implantation, it is possible to reduce a drain leakage and to reliably restrict the p type SiC layer from remaining on the side surface of the trench.

Abstract: In a silicon carbide semiconductor device, a p-type SiC layer is disposed in a corner of a bottom of a trench. Thus, even if an electric field is applied between a drain and a gate when a MOSFET is turned off, a depletion layer in a pn junction between the p-type SiC layer and an n? type drift layer greatly extends toward the n? type drift layer, and a high voltage caused by an influence of a drain voltage hardly enters a gate insulating film. Hence, an electric field concentration within the gate insulating film can be reduced, and the gate insulating film can be restricted from being broken. In this case, although the p-type SiC layer may be in a floating state, the p-type SiC layer is formed in only the corner of the bottom of the trench. Thus, the deterioration of the switching characteristic is relatively low.

Abstract: A sensing device, such as an angular speed detecting device, includes a vibrator for improving detection precision. The vibrator is displaceably supported on a substrate and is vibrated in the direction of an X-axis by driving electrodes. Detecting electrodes detect vibrations of the vibrator in the direction of a Y-axis caused by a Coriolis' force resulting from the angular speed occurring about a Z-axis. Each of the driving and detecting electrodes includes a movable electrode that is connected to the vibrator and that is displaced together therewith on the substrate and a fixed electrode fixed onto the substrate in such a manner as to face the movable electrode. By equalizing conductors connected to fixed electrodes of the driving electrodes and conductors connected to fixed electrodes of the detecting electrodes in length, width, and thickness, respectively, one electrical characteristic is set for those of the wiring portions which function in the same manner.

Abstract: A sensing device, such as an angular speed detecting device, includes a vibrator for improving detection precision. The vibrator is displaceably supported on a substrate and is vibrated in the direction of an X-axis by driving electrodes. Detecting electrodes detect vibrations of the vibrator in the direction of a Y-axis caused by a Coriolis' force resulting from the angular speed occurring about a Z-axis. Each of the driving and detecting electrodes includes a movable electrode that is connected to the vibrator and that is displaced together therewith on the substrate and a fixed electrode fixed onto the substrate in such a manner as to face the movable electrode. By equalizing conductors connected to fixed electrodes of the driving electrodes and conductors connected to fixed electrodes of the detecting electrodes in length, width, and thickness, respectively, one electrical characteristic is set for those of the wiring portions which function in the same manner.