Novel polymeric surfactants for improving chemical mechanical polishing performance of silicon oxide

We investigated the impacts of novel surfactants on oxide chemical mechanic al polishing (CMP) performance. Silica-based potassium hydroxide was formul ated for this study. Two polymeric surfactants, methyl methacrylate (MMA)-b ased CHE and siloxane-based SHE, were added to the slurry for evaluation. P article size, viscosity, surface tension, and contact angle of slurries wer e characterized. Without surfactant, the silica-based slurry withstood up t o 8.5 wt % of solid loading before the silica abrasives segregate and settl e. With the addition of surfactant, however, the slurry held up to 15 wt % of solids without segregation. The CHE-added slurry yielded higher viscosit y and higher oxide CMP removal rate than SHE-added slurry, while the latter exhibited better colloidal dispersion characteristics and lower within-waf er nonuniformity. (C) 2001 The Electrochemical Society. All rights reserved .