Patent ID: 7821043
Filing Date: 2010-10-26
Classification: H01L

Abstract:
1. An insulated gate bipolar transistor comprising: a p-type emitter layer having a thickness of 5 to 50 μm and a dopant concentration of 2×10 an n-type buffer layer provided on the p-type emitter layer; an n-type base layer provided on the n-type buffer layer and having a higher resistivity than the n-type buffer layer; a p-type base layer provided in part of an upper surface of the n-type base layer; an n-type source layer provided in part of an upper surface of the p-type base layer; a trench extending through the n-type source layer and the p-type base layer to the n-type base layer; a gate electrode provided in the trench; and a gate insulating film provided between the gate electrode and an inner surface of the trench.