Patent ID: 7091123

Claim:
A method of forming a metal wiring line, comprising: forming a first insulating film over a semiconductor substrate; forming a second insulating film on said first insulating film; forming a wiring line groove to pass through said second insulating film to an inside of said first insulating film; forming a barrier metal film comprising a first portion formed on an inner surface of said wiring line groove and a second portion formed on said second insulating film; forming a conductive film to fill said wiring line groove and to cover said barrier metal film; removing said conductive film by a first CMP polishing process, using a first slurry, until said barrier metal film is exposed; and removing said first and second portions of said barrier metal film, said conductive film and said second insulating film by a second CMP polishing process using a second slurry which is different from said first slurry, and using said first insulating film as a stopper film, until said first insulating film is exposed, wherein said second slurry used in said second CMP polishing process comprises abrasive particles and has a polishing selection ratio of a polishing rate of said second insulating film to a polishing rate of said first insulating film of at least 5.