Development of a lapping film utilizing agglomerative superfine silica abrasives for edge finishing of a silicon wafer

In the present manufacturing process of a silicon wafer, wafer edge finishing with loose abrasives is essential for preventing wafer breakage and particle contamination due to micro cracks. Loose-abrasive machining, however, has problems involving inefficiency and an unclean working environment. Therefore, fixed-abrasive machining such as film lapping has received attention as an alternative technology, but conventional lapping films have problems involving low finishing efficiency or low finished surface quality. In this study, agglomerative superfine silica abrasives are adopted in the lapping film to overcome these problems. The finishing experiments revealed that a high edge surface quality can be achieved with high efficiency.