Patent ID: 6595830
Filing Date: 2003-07-22
Classification: B24B,H01L

Abstract:
A method of polishing performed on a polishing tool comprised of first, second and third platens, the method comprising:providing a wafer having a patterned layer of insulating material, a barrier metal layer, and a metal layer formed above said wafer; performing a first polishing operation on said wafer at said first platen to remove a majority of said metal layer above said barrier metal layer; performing an endpoint polishing operation on said wafer at said second platen to remove at least some of said metal layer; performing a timed overpolish operation on said wafer at said second platen after said endpoint polishing operation is completed at said second platen; performing a timed polishing operation on said wafer at said third platen to remove substantially all of said barrier metal layer; determining an erosion rate of said patterned layer of insulating material; providing said determined erosion rate to a controller that determines a duration of the timed overpolish operations to be performed on at least one subsequently processed wafer at said second platen; and performing said timed overpolish operation on said at least one subsequently processed wafer at said second platen for the duration determined by said controller.