Patent ID: 8823084

Claim:
A semiconductor device having a breakdown voltage, comprising: a source metallization; a drain metallization; and a semiconductor body, comprising: a drift layer of a first conductivity type in Ohmic contact with the drain metallization; a buffer layer and a field-stop layer of the first conductivity type, the buffer layer adjoining the drift layer and comprising a higher maximum doping concentration than the drift layer; and in a vertical cross-section a plurality of spaced apart compensation regions of a second conductivity type each of which forms a respective first pn-junction with the drift layer, the buffer layer, and the field-stop layer, and is in Ohmic contact with the source metallization, each of the compensation regions comprising a second portion and a first portion arranged between the second portion and the source metallization, the first portions and the drift layer forming a substantially band-shaped first area having a substantially vanishing net doping, the second portions and at least the buffer layer and the field-stop layer forming a substantially band-shaped second area having a net doping of the first conductivity type, wherein a space charge region forms in the second area when a reverse voltage between about 30% and at least 70% of the breakdown voltage is applied between the drain metallization and the source metallization.