Patent ID: 7674716

Claim:
An adjuvant for use in simultaneous polishing of a cationically charged material and an anionically charged material, which forms an adsorption layer on the cationically charged material in order to increase polishing selectivity of the anionically charged material, wherein the adjuvant comprises a polyelectrolyte salt containing: (a) an anionically charged graft type polyelectrolyte that has a weight average molecular weight of 1,000-20,000 and comprises a backbone and a side chain; and (b) a basic material, and the adjuvant is obtained by a method comprising the steps of: (i) polymerizing at least one sub-monomer to obtain a macromonomer that forms the side chain of the graft type polyelectrolyte; and (ii) copolymerizing the macromonomer with a monomer that forms the backbone of the graft type polyelectrolyte.