A method for producing a semiconductor power device includes forming a gate trench from a surface of the semiconductor layer toward an inside thereof. A first insulation film is formed on the inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO.sub.2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

A transistor includes a gate electrode with multiple metals distributed along the width of the gate electrode. Each of the metals in the gate electrode has different work functions. Such a compound gate provides higher linearity when, e.g., operated as a radio frequency transistor.

A transistor includes a gate electrode with multiple metals distributed along the width of the gate electrode. Each of the metals in the gate electrode has different work functions. Such a compound gate provides higher linearity when, e.g., operated as a radio frequency transistor.

A laminated body of an embodiment includes: a silicon layer; a first beryllium oxide layer on the silicon layer; and a diamond semiconductor layer on the first beryllium oxide layer.

A method for producing a semiconductor power device includes forming a gate trench from a surface of the semiconductor layer toward an inside thereof. A first insulation film is formed on the inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

A manufacturing method of a touch panel includes the steps of providing a substrate, forming a first conductive film on the substrate, forming a first mask on the first conductive film, etching the first conductive film to form electrode portions and lower intersect portions of the touch panel, forming an insulating film made of a negative resist on the first conductive film, and forming a contact hole above the electrode portion by removing the insulating film. The steps further include forming a second conductive film on the insulating film, forming a second mask on the second conductive film, etching the second conductive film to form an upper intersect portion connected between two adjacent electrode portions via the contact hole and intersecting with the lower intersect portion, and forming protective film on the second conductive film.

A transistor includes a gate electrode with multiple metals distributed along the width of the gate electrode. Each of the metals in the gate electrode has different work functions. Such a compound gate provides higher linearity when, e.g., operated as a radio frequency transistor.

A manufacturing method of a touch panel includes the steps of providing a substrate, forming a first conductive film on the substrate, forming a first mask on the first conductive film, etching the first conductive film to form electrode portions and lower intersect portions of the touch panel, forming an insulating film made of a negative resist on the first conductive film, and forming a contact hole above the electrode portion by removing the insulating film. The steps further include forming a second conductive film on the insulating film, forming a second mask on the second conductive film, etching the second conductive film to form an upper intersect portion connected between two adjacent electrode portions via the contact hole and intersecting with the lower intersect portion, and forming protective film on the second conductive film.

A method for producing a semiconductor power device includes forming a gate trench from a surface of the semiconductor layer toward an inside thereof. A first insulation film is formed on the inner surface of the gate trench. The method also includes removing a part on a bottom surface of the gate trench in the first insulation film. A second insulation film having a dielectric constant higher than SiO2 is formed in such a way as to cover the bottom surface of the gate trench exposed by removing the first insulation film.

A semiconductor device includes a semiconductor substrate having a main surface and a back surface, a drift region having a first conductivity type, a body region formed in the drift region and having a second conductivity type, a plurality of grooves passing through the body region from the main surface toward the back surface, a gate electrode formed in the plurality of grooves with a gate insulating film interposed therebetween, and an electric field relaxation layer provided below the plurality of grooves in the drift region and having a second conductivity type. The electric field relaxation layer continuously extends over the entire body region.