Patent ID: 7427337

Claim:
An apparatus for electropolishing a conductive layer on a wafer using a solution, the apparatus comprising: an electrode assembly configured to be immersed in a solution and configured to be positioned proximate to a conductive layer on a wafer in contact with said solution, the electrode assembly configured to have a longitudinal dimension extending to at least a periphery of a wafer, the electrode assembly including: a first elongated contact electrode; a first isolator including a side adjacent to the first elongated contact electrode; a first elongated process electrode including a side adjacent to an opposite side of the isolator, the first isolator protruding above top surfaces of the first elongated contact electrode and the first elongated process electrode; a second elongated contact electrode; a second isolator including a side adjacent to the second elongated contact electrode; a second elongated process electrode including a side adjacent to an opposite side of the second isolator, the second isolator protruding above top surfaces of the second elongated contact electrode and the second elongated process electrode; and a third isolator between a side of the first elongated process electrode and a side of the second elongated process electrode, the third isolator protruding above the elongated contact electrodes and the elongated process electrodes, wherein the first elongated contact electrode, the first isolator, the first elongated process electrode, the second elongated contact electrode, the second isolator, the second elongated process electrode, and the third isolator are fastened together by at least one fastener, wherein the isolators each include a plurality of passages vertically extending through the isolators, the passages being partially defined by the electrodes and configured to allow a solution to flow through the electrode assembly, wherein the isolators each comprise a material having a closed pore structure; and a voltage supply configured to apply a potential difference between the contact electrodes and the process electrodes to electropolish the conductive layer on the wafer, wherein the isolators are configured to prevent the contact electrodes and the process electrodes from physically contacting said wafer.