Patent ID: 7847296

Claim:
A silicon carbide semiconductor device comprising: a silicon carbide inclined substrate having a major surface that is inclined relative to a (0001) crystal plane; a first conductivity type silicon carbide layer grown on said major surface of said silicon carbide inclined substrate; and a second conductivity type region formed on the surface of said silicon carbide layer for serving as an element, wherein the periphery of said second conductivity type region is so formed that first electric field strength causing an avalanche breakdown of a same direction as a plane orientation of a prescribed crystal plane is smaller than a second electric field strength causing an avalanche breakdown of a direction different from the plane orientation of said crystal plane with respect to an electric field that is generated when a voltage is applied to said second conductivity type region, and a portion of said periphery of said second conductivity type region is arranged to be in parallel to said prescribed crystal plane, the portion being a narrow strip in a curved corner portion of said periphery of said second conductivity type region.