Chemical mechanical polishing (CMP) of metal and dielectric films was performed using mixed abrasive slurries (MAS). MAS containing alumina and silica particles dispersed in deionized water were evaluated as second step slurries for Cu damascene polishing. It was demonstrated that MAS with proper selection of constituents and composition of abrasive particles can yield desired slurry/CMP characteristics. Based on the results of transmission electron microscope and particle size analysis of the abrasives in these MAS, possible reasons for the improved CMP performance are discussed. (C) 2002 The Electrochemical Society.