Chemical Mechanical Polishing of Ge Using Colloidal Silica Particles and H₂O₂

Abstract

The effects of colloidal silica particles, oxidizer (H 2 O 2 ), and p H on the removal rates (RRs) of Ge have been evaluated. High removal and dissolution rates were obtained in the basic p H regions, likely caused by *OH radicals and rapid dissolution of the dissociation products of germanium hydroxides, while at p H 2, a RR of ∼420 nm/min was obtained with minimal dissolution. The surface quality of polished wafer coupons, measured using atomic force microscopy, was very good. A probable reaction mechanism for Ge removal as a function of p H is proposed.