Abstract

Polishing is a tribochemical process in which specific reactions occur in the local environment of the point of contact between the abrasive particle and the substrate. This local environment is likely to be considerably different from that of the bulk liquid employed in the polishing process. Polishing may therefore be viewed as a spatially activated process. This spatial selectivity has made polishing especially useful in the planarization of electronic devices (CMP). CMP processes for a wide variety of materials (e.g., SiO₂, metal, Si₃N₄, and Si) appear to possess a common removal mechanism, namely the production, reaction, and removal of a solvated surface layer, present either as a discrete species or as a reaction intermediate. This mechanism is reviewed within the context of evolving models for CMP contact mechanics.

© 1996 Optical Society of America