Patent ID: 8071482

Claim:
A manufacturing method of a silicon carbide semiconductor device, comprising: depositing an Al film and an Ni film in that order to form a metal lamination film on a SiC semiconductor substrate; etching the metal lamination film to produce a metal lamination mask in which Ni film portions cover and overhang Al film portions; and then etching a mesa groove at least 10 Î¼m deep in the silicon carbide substrate using an induction-coupled plasma obtained by ionizing a mixed gas of SF 6 , O 2 , and Ar gases, under conditions that the SF 6 , O 2 , and Ar gases are caused to flow at flow rates of 26% to 35%, 7.5% to 8.5%, and 58% to 65% with respect to a total gas flow rate, respectively, wherein the temperature of the silicon carbide semiconductor substrate is 30Â° C.Â±5Â° C. and pressure is kept at 3 Pa or more.