Research on the shape of ground wafer in Back Grinding of Wafer with Outer Rim

Abstract Back Grinding of Wafer with Outer Rim (BGWOR) is a new method for carrier-less thinning of silicon wafers. There are few studies on the shape of wafer in BGWOR. In this paper, the mathematical models of three-dimensional grinding marks, surface shape and radial thickness of wafer in BGWOR were developed. With this model, the pattern of grinding marks and the radial thickness of the wafer under different inclination angles of grinding wheel were simulated by Matlab, then the relationship between the angle of grinding wheel shaft and the grinding marks, surface shape, radial thickness, total thickness variation (TTV) of wafer in BGWOR was also discussed. The inclination angles of grinding wheel have great influence on the surface shape and radial thickness distribution of wafer. Finally, the pilot experiments were conducted to verify the theoretical model of radial thickness of wafer in BGWOR. The study results will provide helpful instruction for improving the flatness of ground wafer.