In recent years, it is strongly demanded that edge roll off of workpiece be diminished in polishing silicon wafers and glass disks and, however, the conventional polishing technologies cannot meet the demand. In this study, using finite element method of a polishing model, the influences of the mechanical properties of a polishing pad on the contact stress distribution near the workpiece edge surface were investigated. As a result, it was found that a double-layered polishing pad had a possibility of suppressing the stress concentration significantly near the workpiece edge, namely, the edge roll off of workpiece. Based on the analytical result, a double-layered polishing pad having extra-fine fiber layer as upper layer and hard polymer layer as lower layer was developed. A series of polishing experiments for silicon wafers and glass plates revealed that the finishing efficiency was much higher than that obtained with conventional polishing pad and the edge roll off of the workpiece could be significantly improved.
