Patent ID: 8366959

Claim:
A stable colloidal dispersion for chemical mechanical polishing comprising: (a) 0.05% to about 10% by weight of an abrasive component and (b) a water-soluble polymer comprising: (i) at least one part B comprising one or more cationic monomeric units, and (ii) at least one part A comprising one or more anionic monomeric units; wherein the dispersion has a pH of between about 1.5 and about 6; wherein polymer is an amphoteric copolymer selected from the group consisting of: (a) a (block A)-(block B) diblock copolymer, wherein the at least one part A is the block A and the at least one part B is the block B; (b) a (block B)-(block A)-(block B) triblock copolymer, wherein the at least one part A is the block A and the at least one part B is the block B; or (c) a (backbone A)-(side chains B) comb copolymer, wherein the at least one part A is the backbone A and the comb copolymer is a plurality of side chains B each bonded to the backbone A at one of their ends.