Patent ID: 7504707

Claim:
A semiconductor, comprising: a first main electrode provided on a first main surface of a semiconductor substrate; a second main electrode provided on a second main surface of said semiconductor substrate opposite to the first main surface in a direction of the thickness of said semiconductor, and configured to allow a main current to flow in the direction of the thickness of said semiconductor substrate; and at least one trench-type gate electrode provided in said first main surface, said semiconductor substrate comprising at least one trench isolation structure provided in said second main surface, and a first impurity region of a first conductivity type and a second impurity region of a second conductivity type provided in said second main surface, wherein said at least one trench isolation structure includes a trench in said second main surface filled with an insulator or a semiconductor of a conductivity type reverse to that of said semiconductor substrate, said at least one trench isolation structure configured to separate said first impurity region and said second impurity region, wherein an exposed surface of said at least one trench isolation structure provided in the portion of said second main surface is level with an exposed surface of said first and second impurity regions, and said second main electrode covers said at least one trench isolation structure and said first and second impurity regions and is electrically commonly connected to them.