Embodiments of a pad assembly for processing a substrate are provided. The pad assembly includes a processing layer having a working surface adapted to process a substrate, a lower layer coupled to and disposed below the processing layer, and an electrode having an upper surface disposed above the lower layer and below the working surface of the processing layer. The upper surface of the electrode is at least partially exposed to the working surface to provide an electrolyte pathway between the upper surface of the electrode and the working surface.