Semiconductor device having semiconductor regions of different conductivity types provided at a predetermined interval along a first direction

Abstract

Among trenches disposed in a striped-shape parallel to a front surface of a semiconductor substrate, a gate electrode at a gate potential is provided in a gate trench, via a gate insulating film; and in a dummy trench, a dummy gate electrode at an emitter electric potential is provided, via a dummy gate insulating film. Among mesa regions, in a first mesa region functioning as a MOS gate, a first p-type base region is provided in a surface region overall. In a second mesa region not functioning as a MOS gate, a second p-type base region is selectively provided at a predetermined interval, along a first direction. At least one of the trenches on each side of a mesa region is a gate trench and at at least one side wall of the gate trench, a MOS gate is driven. As a result, the ON voltage may be reduced.