Patent ID: 6899597

Claim:
A method of polishing a semiconductor wafer having a lower layer formed atop a substrate and having a layer of conductive material formed atop said lower layer, said method comprising: rotating said semiconductor wafer against an abrasive polishing pad; applying a solution to said semiconductor wafer and to said abrasive polishing pad, concurrent with said rotating of said semiconductor wafer, to remove part of said layer of conductive material selectively with respect to said lower layer, said solution including an etchant of said conductive material; said layer of conductive material being selected from the group consisting of tungsten (W), copper (Cu), tantalum (Ta), and titanium (Ti); said lower layer being selected from the group consisting of tantalum nitride (TaN), titanium nitride (TiN) and tungsten nitride (WN); and applying a slurry to said semiconductor wafer and to said abrasive polishing pad concurrent with said applying of said solution.