A polishing pad can smooth out mid-to-high spatial frequency errors automatically due to its rigidity and modeling of the smoothing effect is important. The relationship between surface error and polishing time is built here based on the Bridging model and Preston’s equation. A series of smoothing experiments using pitch tools under different motion manners were performed and the results verified exponential decay between surface error and smoothing time. At the same time, parameters describing smoothing efficiency and smoothing limit were also fitted from the results. This method can be applied to predict the smoothing effect, estimate the smoothing time and compare smoothing rates of different runs.
© 2014 Optical Society of AmericaPDF Article