Published online by Cambridge University Press: 01 February 2011
In this presentation we will discuss polishing performance and related mechanistic aspects of several low solids, low or high pH slurries based on Lewis acids abrasives (TiO2, ZrO2, CeO2), activated by cationic homopolymers, and copolymers with acrylic functionality. In a typical example, a formulation containing 0.5% ZrO2 interacting with 75 ppm cationic copolymer, at pH = 4, resulted in a SiO2 removal rate increase of 34% and a nitride removal rate increase of 97%, as compared with the control lacking the cationic copolymer. We will provide a complex variety of analytical evidence and particle and wafers surface measurements (FT-IR, GPC, surface energy) in order to support our mechanistic hypotheses. We will show with this unique system that 1:1 selectivities of oxide and nitride can be achieved with high removal rates.