Patent ID: 7361076
Filing Date: 2008-04-22
Classification: B24B

Abstract:
1. A method for polishing an object by using a polishing apparatus including a top ring having pressing portions for pressing a back surface of the object, a retainer ring, and a polishing surface, said method comprising: storing in a memory back surface pressures to be applied to the back surface of the object, and polishing amounts corresponding to said back surface pressures; setting a desired polishing profile of the object by setting target polishing amounts for polishing portions; determining back surface pressures as recommended polishing pressures corresponding to said target polishing amounts based on said back surface pressures and said polishing amounts stored in said memory, and on a pressure value of said retainer ring based on a degree of roll-off of the object; calculating a distribution of front surface pressures to be applied to a front surface of the object corresponding to said recommended polishing pressures and said pressure value of said retainer ring; determining estimated polishing amounts based on Preston's equation and said distribution of said front surface pressures; and using said top ring to press the front surface of the object against said polishing surface under a polishing condition including said recommended polishing pressures and said pressure value of said retainer ring when a difference between said estimated polishing amounts and said target polishing amounts is within a predetermined range.