A New Method for the Precise Measurement of Wafer Roll off of Silicon Polished Wafer

A new method using a stylus profiler and a block gauge has been developed to measure the precise profile of wafer roll off occurred within the edge exclusion length. The results from the new method have a good agreement of those using the conventional capacitive gauging tool, when the height deviation of wafer roll off is measured. The new method can specify the exact lateral position with respect to the physical edge of wafer.