An electropolishing apparatus for polishing a metal layer formed on a wafer
(31) includes an electrolyte (34), a polishing receptacle (100), a wafer
chuck (29), a fluid inlet (5, 7, 9), and at least one cathode (1, 2, 3).
The wafer chuck (29) holds and positions the wafer (31) within the
polishing receptacle (100). The electrolyte (34) is delivered through the
fluid inlet (5, 7, 9) into the polishing receptacle (100). The cathode (1,
2, 3) then applies an electropolishing current to the electrolyte to
electropolish the wafer (31). In accordance with one aspect of the present
invention, discrete portions of the wafer (31) can be electropolished to
enhance the uniformity of the electropolished wafer.