Patent ID: 8749017

Claim:
A semiconductor device comprising: a first electrode formed on one principal surface of a first conductivity type semiconductor substrate; a second electrode formed on the other principal surface of the semiconductor substrate; a second conductivity type base layer formed on the one principal surface of the semiconductor substrate so as to be connected to the first electrode; a second conductivity type VLD region provided on an outer circumferential side of the base layer; and a first or second conductivity type stopper layer provided on an outer circumferential side of the VLD region so as to be separated from the VLD region; wherein: the semiconductor device further comprises a second conductivity type first clip layer which is provided between the VLD region and the stopper layer so as to be separated from the VLD region and the stopper layer and which is higher in concentration than the semiconductor substrate; wherein a concentration of the first clip layer is such that a depth of a depletion layer inside the first clip layer is larger than a depth of a non-depleted charge neutral region inside the first clip layer when a voltage equivalent to an avalanche breakdown voltage of the semiconductor device is applied between the second electrode and the first electrode.