Patent ID: 10508221

Abstract:
The present invention provides aqueous chemical mechanical planarization (CMP) polishing compositions comprising one or more dispersions of colloidal silica particles having a zeta potential of from +5 to +50 mV and having one or more aminosilane group, preferably, elongated, bent or nodular colloidal silica particles, or, more preferably, such particles which contain a cationic nitrogen atom, and at least one amine heterocycle carboxylic acid having an isolectric point (pI) of from 2.5 to 5, preferably, from 3 to 4. The compositions have a pH of from 2.5 to 5.3. Preferably, the amine heterocycle carboxylic acid is an amine-containing heterocyclic monocarboxylic acid, such as nicotinic acid, picolinic acid, or isonicotinic acid. The compositions enable enhanced oxide:nitride removal rate ratios.