Patent ID: 8120100
Filing Date: 2012-02-21
Classification: H01L

Abstract:
1. An overlapping trench gate semiconductor device, comprising: a semiconductor substrate, comprising a top surface and a bottom surface with the semiconductor substrate being a first conductive type; a plurality of shallow trenches, disposed on the top surface of the semiconductor substrate; a first conductive layer, disposed on the shallow trenches; a first insulation layer, disposed on surfaces of the shallow trenches, and electrically insulating the first conductive layer and the semiconductor substrate; a plurality of deep trenches, respectively disposed in each of the shallow trenches, extending into the semiconductor substrate under the shallow trenches; a second conductive layer, filling the deep trenches; a second insulation layer, disposed on the top surface of the semiconductor substrate and on surfaces of the deep trenches, and electrically insulating the second conductive layer from the semiconductor substrate and the first conductive layer; a source metal layer, disposed above the second insulation layer and the second conductive layer, and electrically connected to the second conductive layer; a gate metal layer, disposed on the second insulation layer and electrically connected to the first conductive layer; and a drain metal layer, disposed on the bottom surface of the semiconductor substrate.