Chemical Mechanical polishing apparatus

摘要

A chemical mechanical polishing apparatus comprises a platen having a polishing pad thereon, a wafer carrier holding a wafer on the polishing pad, a washer having a cleaning device; and a dresser. The dresser comprises a bottom disk contacting the polishing pad. The dresser can move between the polishing pad and the washer. When the dresser moves into the washer, a diamond zone on the bottom disk cleans the polishing pad, and the cleaning device cleans the diamond zone.