Slurries containing molybdenum oxide abrasives (MoO2, isoelectric point ∼pH 2) with potassium iodate (KIO3) as the oxidizing agent were used to polish copper disks and films, yielding relatively high removal rates. The relatively high copper removal rates observed were due to the in situ generation of I2 by the reaction between KIO3 and MoO2. The surface quality of the polished Cu films, however, was very poor with surface roughness values as high as 140 nm. A second polishing step using a dilute colloidal silica suspension containing H2O2, benzotriazole, and glycine at pH 4 improved the post-polish surface quality, final surface having surface roughness values as low as 0.35 nm.