Patent ID: 8642436

Claim:
A method of manufacturing a silicon carbide semiconductor device, comprising the steps of: preparing a silicon carbide substrate having a surface; forming an etching stop layer on said surface of said silicon carbide substrate; depositing a mask layer on said etching stop layer; forming a first opening surrounded by a first sidewall in said mask layer; forming a first impurity region having a first conductivity type from said surface to a first depth in said silicon carbide substrate by ion implantation through said first opening; forming a mask portion having said mask layer and a spacer layer by depositing said spacer layer on said etching stop layer on which said mask layer has been provided, after said step of forming a first impurity region, said spacer layer covering said first sidewall and said etching stop layer in said first opening; forming a second opening surrounded by a second sidewall in said mask portion by anisotropically etching said spacer layer in said first opening; and forming a second impurity region having a second conductivity type different from said first conductivity type from said surface to a second depth smaller than said first depth in said silicon carbide substrate, by ion implantation through said second opening, an angle of said second sidewall with respect to said surface being 90°±10° across a height as great as said second depth.