Patent ID: 7919811

Claim:
A semiconductor device comprising: a second-conductivity-type base region provided on a first-conductivity-type semiconductor layer; a first-conductivity-type source region provided on the second-conductivity-type base region; a gate insulating film covering an inner wall of a trench which passes through the second-conductivity-type base region and reaching the first-conductivity-type semiconductor layer; a gate electrode buried in the trench via the gate insulating film; a second-conductivity-type region being adjacent to the second-conductivity-type base region below the first-conductivity-type source region, spaced from the gate insulating film, and having a higher impurity concentration than the second-conductivity-type base region; and a second-conductivity-type contact region provided on the second-conductivity-type region and being adjacent to the first-conductivity-type source region, c≧d being satisfied, where d is a depth from an upper surface of the first-conductivity-type source region to a lower end of the gate electrode, and c is a depth from an upper surface of the first-conductivity-type source region to a lower surface of the second-conductivity-type base region, wherein a distance from the gate insulating film to the second-conductivity-type region is 0.3 micrometers or less.