SILICON CARBIDE SEMICONDUCTOR DEVICE AND METHOD FOR MANUFACTURING SILICON CARBIDE SEMICONDUCTOR DEVICE

摘要

A silicon carbide substrate having a gate insulating film provided in contact with a first main surface, having a gate electrode provided in contact with the gate insulating film, and having a source region exposed from first main surface is prepared. A first recess having a first inner wall surface is formed in an interlayer insulating film by performing a first isotropic etching with respect to the interlayer insulating film with use of a mask layer. A second recess having a second inner wall surface is formed by performing a first anisotropic etching with respect to the interlayer insulating film and the gate insulating film with use of the mask layer and thereby exposing the source region from gate insulating film. An interconnection is formed which is arranged in contact with the first inner wall surface and the second inner wall surface and electrically connected to a source electrode.

主权项

1. A method for manufacturing a silicon carbide semiconductor device, comprising the steps of:
preparing a silicon carbide substrate, said silicon carbide substrate having a first main surface and a second main surface opposite to each other, having a gate insulating film provided in contact with said first main surface, having a gate electrode provided in contact with said gate insulating film, and including a first conductivity type region in contact with said first main surface; forming an interlayer insulating film in contact with said gate electrode and said gate insulating film; forming a mask layer in contact with said interlayer insulating film; forming a first recess having a first inner wall surface formed in said interlayer insulating film by performing a first isotropic etching with respect to said interlayer insulating film with use of said mask layer, after said step of forming a first recess, forming a second recess having a second inner wall surface by performing a first anisotropic etching with respect to said interlayer insulating film and said gate insulating film with use of said mask layer and thereby exposing said first conductivity type region of said silicon carbide substrate from said gate insulating film; forming a first electrode in contact with said first conductivity type region; and forming an interconnection being arranged in contact with said first inner wall surface and said second inner wall surface and electrically connected to said first electrode.