Patent ID: 7855412

Claim:
A silicon carbide semiconductor device comprising: a substrate made of silicon carbide and having one of a first conductivity type and a second conductivity type, the substrate having first and second opposing surfaces; a drift layer disposed on the first surface of the substrate, the drift layer made of silicon carbide and having the first conductivity type; a base region disposed on the drift layer and having the second conductivity type; a source region disposed above the base region and having the first conductivity type; a trench penetrating the source region and the base region to the drift layer; a gate insulating layer disposed on a surface of the trench; a gate electrode disposed on a surface of the gate insulating layer in the trench; an interlayer insulating layer disposed above the gate electrode and the source region, the interlayer insulating layer having a contact hole; a first electrode disposed on the interlayer insulating layer, the first electrode electrically coupled with the source region and the base region through the contact hole; a second electrode disposed on the second surface of the substrate; and a second conductivity-type layer disposed at a portion of the base region located under the source region, the second conductivity-type layer having the second conductivity type and having an impurity concentration higher than the base region, the second conductivity-type layer extending from an inside of the contact hole to an outside of the contact hole toward the trench in a direction parallel to the first surface of the substrate, wherein an inversion channel is provided at a surface portion of the base region located on a side surface of the trench and electric current flows between the first electrode and the second electrode through the source region and the drift layer by controlling a voltage applied to the gate electrode.