An electroplating apparatus includes a reactor vessel having a segmented
anode array positioned therein for effecting electroplating of an
associated workpiece such as a semiconductor wafer. The anode array
includes a plurality of ring-like anode segments which are preferably
positioned in concentric, coplanar relationship with each other. The
anode segments can be independently operated to create varying electrical
potentials with the associated workpiece to promote uniform deposition of
electroplated metal on the surface of the workpiece.