High withstand voltage field effect type semiconductor device

Abstract

It is intended to provide a high withstand voltage field effect type semiconductor device that relaxes electric fields in a semiconductor substrate without thickening thickness of a drift region and achieves withstand-ability against high voltage without sacrificing ON-voltage, switch-OFF characteristics, and miniaturization. A field effective type semiconductor device comprises emitter regions 100, 104 and gate electrodes 106 and the like on a surface (upper surface in FIG. 2), a collector region 101 and the like on the other surface (lower surface in FIG. 2), wherein N− field dispersion regions 111 of low impurity concentration are arranged between P body regions 103 facing to gate electrodes 106 and an N drift region 102 below P body regions 103. Thereby, electric field between collector and emitter is relaxed and high withstand voltage field effect type semiconductor device is realized. Another field dispersion region can be arranged between the N drift region 102 and P+ collector region 101 below the N drift region 102.

Dependencies are inferred from the claim text.