ADJUSTING POLISHING RATES BY USING SPECTROGRAPHIC MONITORING OF A SUBSTRATE DURING PROCESSING

摘要

A computer implemented method includes receiving a sequence of current spectra of reflected light from a substrate; comparing each current spectrum from the sequence of current spectra to a plurality of reference spectra from a reference spectra library to generate a sequence of best match reference spectra; determining a goodness of fit for the sequence of best match reference spectra; and determining at least one of whether to adjust a polishing rate or an adjustment for the polishing rate, based on the goodness of fit.