SiCN and SiN Polishing Slurries and Polishing Methods Using The Same

摘要

A method is disclosed for polishing a wafer with a slurry. In the method, the wafer comprises at least one of silicon carbonitride (SiCN) and silicon nitride (SiN), and further comprises one or both of silicon dioxide (SiO₂) and poly silicon, and a removal rate of SiCN is greater than a removal rate of poly silicon, and the removal rate of poly silicon is greater than a removal rate of SiO₂, and where the slurry comprises up to about 15 wt % of surface-modified colloidal silica particles which have a primary particle size of less than about 35 nm, and the surface-modified colloidal silica particles comprise a plurality of acid moieties or salts thereof.