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

We investigated the impacts of novel surfactants on oxide chemical mechanical polishing (CMP) performance. Silica-based potassium hydroxide was formulated for this study. Two polymeric surfactants, methyl methacrylate (MMA)-based CHE and silixane-based SHE, were added to the slurry for evaluation. Particle size, viscosity, surface tension, and contact angle of slurries were characterized. Without surfactant, the silica-based slurry withstood up to 8.5 wt% of solid loading before the silica abrasives segregate and settle. With the addition of surfactant, however, the slurry held up to 15 wt% of solids without segregation. The CHE-added slurry yielded higher viscosity and higher oxide CMP removal rate than SHE-added slurry, while the latter exhibited better colloidal dispersion characteristics and lower within-wafer nonuniformity.