Patent ID: 8517796
Filing Date: 2013-08-27
Classification: B24B

Abstract:
1. A dressing apparatus for dressing a polishing pad, said dressing apparatus comprising: a dresser disk to be brought into sliding contact with the polishing pad; a vertically movable dresser drive shaft coupled to said dresser disk; a pressing mechanism configured to receive a supply of a gas to press said dresser disk against the polishing pad through said vertically movable dresser drive shaft; a pressure-measuring device configured to measure pressure of the gas supplied to said pressing mechanism; a load-measuring device incorporated in said vertically movable dresser drive shaft and configured to measure a load acting on said vertically movable dresser drive shaft, said load-measuring device being located between said pressing mechanism and said dresser disk; and a pressure controller configured to control the pressure of the gas supplied to said pressing mechanism, calculate a pressing force of said dresser disk against the polishing pad by adding a predetermined amount of correction to a measurement value of said load-measuring device, the predetermined amount of correction being a weight of a lower part of a dresser assembly that comprises vertically movable components including said dresser disk and said vertically moveable dresser drive shaft, said lower part of said dresser assembly being lower than said load-measuring device, and establish a relationship between the pressure of the gas and the pressing force of said dresser disk against the polishing pad, based on measurement values of said pressure-measuring device and the calculated pressing force of said dresser disk.