Patent ID: 7071105

Claim:
A method of polishing a substrate comprising: (i) contacting a substrate comprising a silicon-containing dielectric layer with a chemical-mechanical polishing system comprising: (a) about 0.5 wt. % or less of an inorganic abrasive consisting, essentially of ceria, (b) a polishing additive bearing a functional group with a pK a of about 4 to about 9, wherein the polishing additive is selected from the group consisting of arylamines, aminoalcohols, aliphatic amines, heterocyclic amines, hydroxamic acids, aminocarboxylic acids, cyclic monocarboxylic acids, unsaturated monocarboxylic acids, substituted phenols, sulfonamides, thiols, salts thereof, and combinations thereof, and (c) a liquid carrier, wherein the polishing system has a pH of about 7 or less and does not contain a significant amount of cross-linked polymer abrasive particles that are electrostatically associated with the inorganic abrasive, and (ii) abrading at least a portion of the silicon-containing dielectric layer to polish the substrate.