Patent ID: 6217419
Filing Date: 2001-04-17
Classification: B24B

Abstract:
A method of chemical-mechanical polishing comprising the steps of:rotating a polishing table having a polishing pad positioned at an annular configured polishing area;directing a chemical-mechanical polishing slurry onto the polishing pad while biasing a semiconductor wafer carried by a wafer carrier into the polishing pad for planarizing a surface of the semiconductor wafer;exerting a counter force against the downward pressure exerted by the wafer carrier onto the semiconductor wafer by actuating fluid pressure upward through an annular trench formed in the polishing table at the annular configured polishing area and onto the bottom surface of an annular diaphragm that is positioned under the polishing pad; andcontrolling the fluid pressure for changing the counterforce and upward biasing pressure against the bottom surface of the annular diaphragm.