Patent ID: 7790015
Filing Date: 2010-09-07
Classification: B23H,B24B,G01N,H01L,H04N

Abstract:
1. A method for removing conductive materials from a semiconductor substrate by electro-processing, comprising: pressing a conductive layer disposed on a substrate in contact with a conductive surface of a polishing pad, wherein the substrate is offset from a center line of the polishing pad; providing sufficient electrolyte on the polishing pad to establish a conductive path between the conductive layer and an electrode assembly disposed below the polishing pad, the electrode assembly having a plurality of zones that are independently biasable relative to the conductive surface of the polishing pad; rotating the polishing pad while the substrate is pressed against the conductive surface; providing electrical bias between the conductive surface and the zones of the electrode assembly; sensing charge removed from the conductive layer through each zone of the electrode assembly; determining a time that at least one portion of the substrate is associated with each of the plurality of zones of the electrode to determine the charge removed from each portion of the substrate; comparing the charge removed from each portion of the substrate to a target charge removed and; independently controlling bias applied between each zone and the conductive surface in response to the comparison.