Abstract: At the time of performing a polishing process on a tungsten film and a silicon oxide film, based on the relation between a residual step and pattern density preliminarily obtained while changing polishing parameters, from pattern density of plugs in the polishing step and a predetermined residual step required, polishing parameters are determined so that a residual step does not exceed a predetermined residual step “h”. With the determined polishing parameters, the polishing process is performed on the tungsten film and the silicon oxide film so that the films are planarized, and plugs are formed in contact holes. As a result, a semiconductor device in which a step does not exceeds a predetermined residual step by a polishing process is obtained.

Abstract: A hard mask material 2 such as a silicon oxide film is formed on an aluminum alloy film 3. The hard mask material 2 is patterned in the form of a thick film wiring 6, followed by etching the aluminum alloy film 3 to a given depth through the mask. A resist 5 applied to the thin film portion of the aluminum alloy film 3 is patterned in the form of a thin film wiring 7. Etching through the resist 5 and the hard mask material 2 as a mask is effected to form the thick film wiring 6 and the thin film wiring 7 in the same layer.

Abstract: At the time of performing a polishing process on a tungsten film and a silicon oxide film, based on the relation between a residual step and pattern density preliminarily obtained while changing polishing parameters, from pattern density of plugs in the polishing step and a predetermined residual step required, polishing parameters are determined so that a residual step does not exceed a predetermined residual step “h”. With the determined polishing parameters, the polishing process is performed on the tungsten film and the silicon oxide film so that the films are planarized, and plugs are formed in contact holes. As a result, a semiconductor device in which a step does not exceeds a predetermined residual step by a polishing process is obtained.

Abstract: A hard mask material 2 such as a silicon oxide film is formed on an aluminum alloy film 3. The hard mask material 2 is patterned in the form of a thick film wiring 6, followed by etching the aluminum alloy film 3 to a given depth through the mask. A resist 5 applied to the thin film portion of the aluminum alloy film 3 is patterned in the form of a thin film wiring 7. Etching through the resist 5 and the hard mask material 2 as a mask is effected to form the thick film wiring 6 and the thin film wiring 7 in the same layer.