Electrochemical planarization of interconnect metallization

Studies of the electropolishing of copper are reviewed. Recent work intended to demonstrate the electrochemical planarization of the overburden in electroplated copper interconnect metallization is emphasized. Furthermore, two common reaction mechanisms invoked to explain the mass-transfer limitation required to achieve electropolishing are outlined and discussed within the context of anodic leveling, which has been more recently called electrochemical planarization. Finally, scaling arguments are used to demonstrate practical considerations for tool development and to speculate about uncertainties in anodic leveling theories. © 2005 IBM.