Patent ID: 8998676
Filing Date: 2015-04-07
Classification: B24B

Abstract:
1. A method of selecting a retaining ring, comprising: polishing a first test substrate with the first test substrate held in a carrier head having a first retaining ring having an upper portion and a lower portion with a first stiffness and a first thickness; measuring polishing uniformity of the first test substrate; selecting based on the polishing uniformity a second retaining ring with an upper portion and a lower portion with a second stiffness and a second thickness; polishing a second test substrate with the second test substrate held in the carrier head having the second retaining ring; and polishing a plurality of device substrates using a plurality of carrier heads having a plurality of retaining rings, each retaining ring of the plurality of retaining rings having an upper portion and a lower portion with the second stiffness and the second thickness.