| 摘要 |
PURPOSE:To reduce an ON resistance by incorporating the one conductivity type impurity region the same as a substrate and reverse conductivity type impurity region to a semiconductor substrate on the back surface drain region of a semiconductor substrate. CONSTITUTION:A gate electrode 3 and a source region 4 are formed on the front surface side of one conductivity type semiconductor substrate 1, and a drain region is formed on the back surface side. The drain region has a structure that the same conductivity type impurity region 7 as the substrate 1 and a reverse conductivity type impurity region 8 arriving at the substrate 1 through the region 7 to the substrate 1 have a universal contact connected with a drain electrode 9. The ON resistance of unipolar transistor and the ON resistance of bipolar transistor are connected in parallel to reduce the resistance between the source and the drain, i.e., the ON resistance. |
