Wide band gap semiconductor device with surface insulating film

A semiconductor device including a MISFET (Metal Insulator Field Effect Transistor), the semiconductor device comprising:

• a semiconductor layer made of SiC, the semiconductor layer having a cell portion including a plurality of unit cells, an outer peripheral portion arranged around the cell portion, a base surface, and a lower surface formed at a relatively low height position with respect to the base surface;
• a gate electrode provided on the semiconductor layer via a gate insulating film;
• a gate pad;
• a first surface insulating film formed on a surface of the semiconductor layer in the cell portion, the first surface insulating film covering the gate electrode and exposing a source portion including the lower surface through a contact hole;
• a second surface insulating film formed on the surface of the semiconductor layer in the outer peripheral portion;
• and
• a source pad formed on the first surface insulating film and electrically connected to the source portion through the contact hole, wherein the source pad has a step caused by a level difference between a surface of the first surface insulating film and the lower surface of the source portion, and
• a thickness of the first surface insulating film is smaller than a thickness of the second surface insulating film.