Patent ID: 8952450
Filing Date: 2015-02-10
Classification: H01L

Abstract:
1. A semiconductor device comprising; a first semiconductor region of a first conductivity type; a second semiconductor region of a second conductivity type disposed on the first semiconductor region; a third semiconductor region of the first conductivity type disposed selectively on the second semiconductor region; a trench extending through the third and second semiconductor regions and into the first semiconductor region; a first electrode disposed in the trench with a first insulator film interposed between a side wall of the trench and the first electrode, the first electrode being disposed in a bottom portion of the trench; a control electrode disposed in the trench with a second insulator film interposed between the side wall of the trench and the control electrode, the control electrode being disposed above the first electrode; a second electrode in contact with the third semiconductor region; and a further semiconductor region of the first conductivity type doped more heavily than the first semiconductor region, the further semiconductor region being disposed in a portion of the first semiconductor region and being positioned adjacent the second semiconductor region and the trench, wherein the first electrode is positioned on a first semiconductor region side of a boundary between the first semiconductor region and the second semiconductor region, wherein the first electrode is connected electrically to the second electrode, and wherein the first insulator film is thicker than the second insulator film.