US Patent 7898029 Semiconductor device internally having insulated gate bipolar transistor

The semiconductor device includes a P-type semiconductor region and an MOS transistor. MOS transistor includes a gate electrode, a collector electrode, a drain electrode, an N-type impurity region and a P-type impurity region. N-type impurity region is electrically connected to the drain electrode. P-type impurity region is electrically connected to the collector electrode. P-type impurity region is electrically connected to the drain electrode. The semiconductor device further includes an N-type impurity region and an electrode. N-type impurity region is electrically connected to the gate electrode. The electrode is formed on the P-type semiconductor region with an insulating film therebetween, and is electrically connected to gate electrode. Thereby, an element footprint can be reduced while maintaining characteristics.