US Patent 7708621 Polishing apparatus and method of reconditioning polishing pad

This polishing apparatus includes a head that holds a semiconductor wafer, a polishing pad that polishes a surface to be polished of the semiconductor wafer held by the head, and a dresser that reconditions the polishing pad by cutting the polishing pad. The polishing apparatus polishes a surface to be polished of the semiconductor wafer while causing the head and the polishing pad to rotate and reconditions the polishing pad by use of the dresser before and after polishing the surface to be polished. The polishing apparatus of the present invention supports at least two dressers so that the dressers can rotate on their own axes and further includes a dresser oscillator that causes the dressers to oscillate simultaneously on the polishing pad.