Patent ID: 9082683
Filing Date: 2015-07-14
Classification: H01L

Abstract:
1. 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, said second sidewall having a substantially uniform thickness across a height as great as said second depth, wherein an ion implantation angle in said step of forming a second impurity region is not smaller than 3° and not greater than 6°, and a surface of said silicon carbide substrate is a (0-33-8) plane of a hexagonal crystal.