Abstract: A switch device includes: a switch; an operation section disposed to face the switch; a first resilient section that is deformed by first pressing force derived from the operation section; and a second resilient section that is brought into contact with the switch by the deformation of the first resilient section, and is deformed to activate the switch by second pressing force greater than the first pressing force.

Abstract: Problems with a conventional mesa type semiconductor device, which are deterioration in a withstand voltage and occurrence of a leakage current caused by reduced thickness of an insulation film on an inner wall of a mesa groove corresponding to a PN junction, are solved using an inexpensive material, and a mesa type semiconductor device of high withstand voltage and high reliability is offered together with its manufacturing method. A stable protection film made of a thermal oxide film is formed on the inner wall of the mesa groove in the mesa type semiconductor device to cover and protect the PN junction, and an insulation film having negative electric charges is formed to fill a space in the mesa groove covered with the thermal oxide film so that an electron accumulation layer is not easily formed at an interface between an N? type semiconductor layer and the thermal oxide film.

Abstract: The invention is directed to reduction of a manufacturing cost and enhancement of a breakdown voltage of a PN junction portion abutting on a guard ring. An N? type semiconductor layer is formed on a front surface of a semiconductor substrate, and a P type semiconductor layer is formed thereon. An insulation film is formed on the P type semiconductor layer. Then, a plurality of grooves, i.e., a first groove, a second groove and a third groove are formed from the insulation film to the middle of the N? type semiconductor layer in the thickness direction thereof. The plurality of grooves is formed so that one of the two grooves next to each other among these, that is closer to an electronic device, i.e., to an anode electrode, is formed shallower than the other located on the outside of the one. Then, an insulating material is deposited in the first groove, the second groove and the third groove. The lamination body of the semiconductor substrate and the layers laminated thereon is then diced along dicing lines.

Abstract: The invention is directed to reduction of a manufacturing cost and enhancement of a breakdown voltage of a PN junction portion abutting on a guard ring. An N? type semiconductor layer is formed on a front surface of a semiconductor substrate, and a P type semiconductor layer is formed thereon. An insulation film is formed on the P type semiconductor layer. Then, a plurality of grooves, i.e., a first groove, a second groove and a third groove are formed from the insulation film to the middle of the N? type semiconductor layer in the thickness direction thereof. The plurality of grooves is formed so that one of the two grooves next to each other among these, that is closer to an electronic device, i.e., to an anode electrode, is formed shallower than the other located on the outside of the one. Then, an insulating material is deposited in the first groove, the second groove and the third groove. The lamination body of the semiconductor substrate and the layers laminated thereon is then diced along dicing lines.

Abstract: Problems with a conventional mesa type semiconductor device, which are deterioration in a withstand voltage and occurrence of a leakage current caused by reduced thickness of an insulation film on an inner wall of a mesa groove corresponding to a PN junction, are solved using an inexpensive material, and a mesa type semiconductor device of high withstand voltage and high reliability is offered together with its manufacturing method. A stable protection film made of a thermal oxide film is formed on the inner wall of the mesa groove in the mesa type semiconductor device to cover and protect the PN junction, and an insulation film having negative electric charges is formed to fill a space in the mesa groove covered with the thermal oxide film so that an electron accumulation layer is not easily formed at an interface between an N? type semiconductor layer and the thermal oxide film.

Abstract: In the present invention, a vertical type MOSFET and a Schottky barrier diode which are used as a switching device of a DC--DC converter are formed on the same semiconductor substrate. Further, a barrier metal which is required for the Schottky barrier diode is also formed on an electrode portion of the vertical type MOSFET. In addition, a Schottky barrier diode forming region is formed to have low impurity concentration than a vertical type MOSFET forming region.