end of an igbt chip but is an arbitrary position in the igbt illustrated for convenience this also applies to other sectional views referred here the inside region surrounded by the breakdown resistant structure 39 has in addition to the igbt active section 20 a circuit section 21 and a contact p type region 8 surrounding the circuit section 21 and contacting a p well region 9 of the circuit section 21 the emitter electrode 3 1 is connected electrically to the contact p region 8 the circuit section 21 has an n channel mosfet in which an n drain region 10 1 and an n source region 10 2 are formed as surface regions in the surface of the p well region 9 and a gate electrode 12 is on the portion of the p well region 9 located between the drain region 10 1 and the source region 10 2 with a gate insulating film 11 interposed in between the n drain region 10 1 is connected to the emitter electrode 3 1 as described above to prevent destruction of the igbt due to overcurrent overvoltage or overheating the circuit section 21 monitors the operation status and controls the gate signal in the event of abnormality in the first embodiment a p type region 5 collector region is formed on the back surface side right under the igbt active section 20 in the other area of the back surface side the back surface of the drift layer semiconductor substrate 4 is in direct contact with the collector electrode 40 i e forming a schottky junction it is preferable to use as a metal material.