摘要 |
A trench gate type MISFET and a diode are formed in a semiconductor substrate. First and second trenches are formed in the semiconductor substrate. A gate electrode is formed in the first trench through a gate insulating film. A dummy gate electrode is formed in the second trench through a dummy gate insulating film. A cathode n+-type semiconductor region and an anode p-type semiconductor region are formed in the semiconductor substrate and the second trench is formed so as to surround the n+-type semiconductor region in a planar view. A part of the anode p-type semiconductor region is formed directly below the n+-type semiconductor region, so that a PN junction is formed between the part of the anode p-type semiconductor region and the n+-type semiconductor region. Thereby a diode is formed. The dummy gate electrode is electrically coupled to one of an anode and a cathode. |