Patent ID: 7306637
Filing Date: 2007-12-11
Classification: B24B,C09G,C09K

Abstract:
1. A chemical-mechanical polishing system comprising: (a) an abrasive, (b) water, and (c) a positively charged polyelectrolyte with a molecular weight of about 15,000 or more and about 2,000,000 or less, wherein the positively-charged polyelectrolyte is a polymer or surfactant comprising positively-charged functional groups, wherein the positively-charged functional groups are selected from the group consisting of primary amines, secondary amines, tertiary amines, quaternary amines, and combinations thereof, and wherein either (1) the positively-charged polyelectrolyte further comprises (i) repeating units comprising functional groups selected from the group consisting of phosphonic acids, phosphonates, sulfates, sulfonic acids, sulfonates, phosphates, carboxylic acids, carboxylates, and mixtures thereof, (ii) repeating units selected from the group consisting of ethylene oxide, propylene oxide, vinyl acetate, and mixtures thereof, or (iii) one or more repeating units comprising functional groups selected from the group consisting of amides, imides, and mixtures thereof, or (2) the positively charged polyelectrolyte is a siloxane polymer or copolymer containing pendant amine groups; wherein the abrasive comprises particles that are electrostatically associated with the positively charged polyelectrolyte, and wherein the particles that are electrostatically associated with the positively charged polyelectrolyte have a negative zeta potential and are obtained by treating particles having a positive zeta potential with a charge-reversing agent.