Chemical mechanical polishing of scratched and pitted copper films was performed with a chemical solution containing 3 wt% hydrogen peroxide (H2O2), 2 mM benzotriazole, and a complexing agent, at pH 4, in the presence and absence of 0.1 wt % of; 10 to 20 nm colloidal silica particles. While the chemical solution alone was able to clear shallow scratches and pits, some as deep as 40 nm, the addition of 0.1 wt % of colloidal silica allowed the planarization of scratches as deep as similar to320 nm and pits as deep as 350 nm, all after a 60 s polish time. (C) 2003 The Electrochemical Society.