Semiconductor device comprising semiconductor substrate and having diode region and IGBT region

摘要

A semiconductor device includes a semiconductor substrate in which a diode region and an IGBT region are formed, wherein a lower surface side of the semiconductor substrate comprises a low impurity region provided between a second conductivity type cathode region of the diode region and a first conductivity type collector region of the IGBT region. The low impurity region includes at least one of a first conductivity type first low impurity region which has a lower density of first conductivity type impurities than that in the collector region and a second conductivity type second low impurity region which has a lower density of second conductivity type impurities than that in the cathode region.