Patent ID: 7211861

Claim:
An insulated gate semiconductor device comprising: an isolating structure shaped in a circulating section along the periphery of a semiconductor substrate so as to isolate that part from an inside device region, a peripheral diffusion region of the semiconductor substrate located outside the isolating structure, a plurality of cell structures defined in the device region and divided in segments by insulated trench-shaped gates so as to have a base region covered with an emitter region in its upper surface, a collector region, and an emitter electrode electrically connected to the emitter region and the base region, a dummy base region contiguous to the cell structures and configured as a base region that has its upper surface left without the emitter region connected to the emitter electrode, and a connection part to electrically connect the peripheral diffusion region to the emitter electrode, wherein said emitter electrode is divided in segments of two rows and a plurality of columns, and said connection parts are provided at an end of said segments, and wherein a gate electrode is disposed at a corner of either of the outermost columns, the peripheral diffusion region extending between the gate electrode and one of the divided emitter electrode in the column that the corner belongs to, and the connection part is provided between the extended peripheral diffusion region and one of the divided emitter electrode in the column.