Patent ID: 7498658

Claim:
A trench gate type insulated gate bipolar transistor comprising; a first semiconductor layer having a first conductive type; a second semiconductor layer having a second conductive type and disposed on a surface of the first semiconductor layer; a third semiconductor layer having the first conductive type and disposed on a surface of the second semiconductor layer; a plurality of trenches penetrating the third semiconductor layer and reaching the second semiconductor layer, wherein the third semiconductor layer includes a plurality of first regions and a plurality of second regions, which are electrically separated by the trenches; a gate insulation film disposed on an inner wall of each trench; a gate electrode disposed on the gate insulation film in each trench; a fourth semiconductor layer having the second conductive type, wherein the fourth semiconductor layer is disposed in a surface portion of each first region of the third semiconductor layer and contacts each trench; a first electrode electrically connecting to the first region of the third semiconductor layer and the fourth semiconductor layer without electrically connecting to the second region of the third semiconductor layer; a second electrode electrically connected to the first semiconductor layer; and an outer trench, wherein the first regions and the second regions are alternately arranged, at least two second regions are continuously connected together so that the two second regions are integrated into one body, and the outer trench surrounds the two second regions so that the two second regions are isolated.