Patent ID: 8377811
Filing Date: 2013-02-19
Classification: H01L

Abstract:
1. A method for manufacturing a silicon carbide semiconductor device, comprising: (a) preparing a silicon carbide substrate; (b) forming an epitaxial layer on a first main surface of said silicon carbide substrate; (c) forming a protective film on said epitaxial layer; (d) forming a first metal layer on a second main surface of said silicon carbide substrate; (e) applying, after said step (d), heat treatment to said silicon carbide substrate at a predetermined temperature to form an ohmic junction between said first metal layer and the second main surface of said silicon carbide substrate; (f) removing, after said step (e), said protective film from a surface of said epitaxial layer; (g) forming, after said step (f), a Ti layer on said epitaxial layer; (i) applying, after said step (g), patterning to said Ti layer by etching; (h) applying, after said step (i), heat treatment to said silicon carbide substrate at temperature from 400° C. to 600° C. to form a Schottky junction of desired characteristics between said Ti layer and said epitaxial layer, (m) wherein said protective film prevents a surface of said epitaxial layer from being exposed to impurities generated during said heat treatment of said step (e) and is entirely removed from said surface of said epitaxial layer before forming said Ti layer in said step (g).