An apparatus and a method for chemical mechanical polishing a metal on a semiconductor wafer capable of achieving improved pad life are disclosed. In the apparatus, in addition to a first spray nozzle used for spraying a slurry solution onto the top of a polishing pad, a second spray nozzle is provided for mounting juxtaposed to a conditioning pad for dispensing a cleaning solution capable of dissolving polishing debris formed on the polishing pad surface. The apparatus may further include at least one cleaning solution reservoir for storing and delivering a cleaning solution to the second spray nozzle. The method can be advantageously carried out in two-steps during which a first cleaning solution is sprayed onto the pad surface for dissolving the polishing debris, and then a second cleaning solution is sprayed onto the pad surface for removing or flushing away the dissolved debris. In one illustration for the removal of oxides of copper, an acid-containing or ammonium hydroxide-containing cleaning solution is used advantageously to dissolve the oxides, and then deionized water is used to remove the dissolved debris from the pad surface.