It is an object of the present invention to provide a process for a fluorine containing carbon film (a CF film), which can put an interlayer insulator film of a fluorine containing carbon film into practice. A conductive film, e.g., a TiN film 41, is formed on a CF film 4. After a pattern of a resist film 42 is formed thereon, the TiN film 41 is etched with, e.g., BCl3 gas. Thereafter, when the surface of the wafer is irradiated with O2 plasma, the CF film is chemically etched, and the resist film 42 is also etched. However, since the TiN film 41 functions as a mask, a predetermined hole can be formed. Although an interconnection layer of aluminum or the like is formed on the surface of the CF film 4, the TiN film 41 functions as an adhesion layer for adhering the interconnection layer to the CF film 4 and serves as a part of the interconnection layer. As the mask, an insulator film of SiO2 or the like may be substituted for the film.