Patent ID: 6830504
Filing Date: 2004-12-14
Classification: B24D,C09G,H01L

Abstract:
A method of polishing a metal layer, comprising the steps of:providing a structure having an upper patterned dielectric layer; the patterned dielectric layer having an opening formed therein; forming a barrier layer over the patterned upper dielectric layer, the barrier layer lining the opening; forming a metal layer over the barrier layer, filling the opening; conducting a first polish step employing a first slurry composition, the first polish step removing a portion of the overlying metal layer; conducting a second polish step employing the first slurry composition, the second polish step polishing the partially removed overlying metal layer and exposing portions of the barrier layer overlying the patterned upper dielectric layer; conducting a third polish step employing a second slurry composition, the third polish step removing the exposed barrier layer portions and exposing underlying portions of the patterned upper dielectric layer; and conducting a fourth polish step employing the second slurry composition and BTA, the fourth polish step buffing the exposed upper dielectric layer portions.