Patent ID: 8039879

Claim:
A semiconductor device comprising: a semiconductor substrate of a first-conductivity type having a one major surface and an opposite major surface opposite the one major surface; an IGBT section comprising: an active section on a side of the one major surface of the semiconductor substrate, including a gate electrode and an emitter electrode; a breakdown-resistant structure surrounding the active section; a collector region of a second-conductivity type on a side of the opposite major surface of the semiconductor substrate; and a collector electrode in contact with the opposite major surface of the semiconductor substrate; a first high-concentration region of the first-conductivity type in the one major surface of the semiconductor substrate, outside the breakdown-resistant structure, and higher in impurity concentration than the semiconductor substrate; a Zener diode connected to the high-concentration region and the gate electrode, with an anode of the Zener diode connected to the gate electrode; a control circuit section disposed inside the breakdown-resistant structure on the side of the one major surface of the semiconductor substrate; and a well region of the second-conductivity type in the one major surface of the semiconductor substrate and surrounding the control circuit section; wherein the well region connects to the emitter electrode of the IGBT section, wherein the control circuit protects the IGBT section by detecting an abnormal state of the IGBT section through the emitter electrode and controls a gate voltage of the IGBT section, wherein the collector region is in the opposite major surface of the semiconductor substrate positioned underneath the active section; and wherein the collector region is not positioned vertically underneath the control circuit section.