A wafer with a lacquer layer applied to it is checked automatically by lighting the wafer directly, so that the lacquer layer reflects the light. Resultant reflectance values of the reflected light are ascertained and buffer-stored and compared with corresponding values for a comparison wafer....http://www.google.ca/patents/US5825499?utm_source=gb-gplus-sharePatent US5825499 - Method for checking wafers having a lacquer layer for faults
