Patent ID: 6969308

Claim:
An apparatus for chemical mechanical polishing for planarizing a surface of wafer on which a conductive layer is formed, the apparatus comprising: a polishing pad ( 34 a ); a slurry supplying device ( 37 a ) which supplies slurry ( 37 S) on the polishing pad ( 34 a ); a polishing head ( 38 A) which presses the wafer (W) against the polishing pad ( 34 a ); a voltage application device ( 11 ) which applies voltage between the wafer (W) and the polishing pad ( 34 a ) to effect electropolishing; and an atmosphere alteration device ( 11 ) for making an atmosphere in a polishing section ( 16 ) around the polishing pad different from ambient air, wherein the electropolishing is effected within the atmosphere having a composition different from the ambient air.