MOS type semiconductor device

A MOS type semiconductor device, comprising:

• a stripe-shaped plan-view pattern of protruding semiconductor region on one principal surface of a first conductivity type semiconductor substrate, the protruding semiconductor region having
• a second conductivity type region sandwiched between an upper side first conductivity type first region and a lower side first conductivity type second region,
• a top flat portion including a depression region with a depth reaching the second conductivity type region from a surface of the upper side first conductivity type first region, and
• an inclined portion between the top flat portion and a bottom flat portion around the protruding semiconductor region;
• and
• a gate electrode covering a surface of the inclined portion of the second conductivity type region across a gate insulator, the gate electrode having
• a first end portion on a surface within the inclined portion, and
• a second end portion on a surface of the lower side first conductivity type second region on the side of and in the vicinity of the second conductivity type region,
• the gate electrode terminating on the inclined portion without extending onto the top flat portion.