PURPOSE: To improve the selective ratio against an SiO2 film and a silicon nitride film which are made etching rate and a stopper in comparison with the case wherein a conventional Freon series gas is used by using an SiCl4 + Cl2 series gas for the etching of SiC by RIE.

CONSTITUTION: A mixed gas of SiCl4 and Cl2 is used as an etchant for the etching of silicon carbide by reactive ion etching. For example, a stopper film 13 such as silicon nitride is grown on a substrate 11, a contact hole is opened, an SiC film 12 is grown and patterned by providing a resist 15 on the film 12. This is mounted on a susceptor 22 in RIE equipment 21, an SiCl4 + Cl2 series gas which is an etchant gas is supplied in the RIE equipment 21 from an introduction pipe 25 and etched by exposing the SiC film 12 in plasma 28. In this case, SiCl4:Cl2 can be set within 10:1 and the pressure within the RIE equipment can be set within 0.01W0.05 Torr.