Chemical Mechanical Polishing for Silicon Wafer Planarization by Exerting Partial Region Load

Based on the circular plate contact theory of elastic mechanics, the relationship of the flatness error of polished silicon wafer to the contact pressure distribution between silicon wafer and polishing pad is analyzed. A new method for equating the contact pressure distribution by exerting partial region load on silicon wafer surface is suggested, and is investigated by polishing experiments. The silicon wafer with flatness error less than 0.33μm is obtained. This study provides a new way for chemical mechanical planarization.