SCANNING OPTICAL MICROELLIPSOMETER FOR PURE SURFACE PROFILING

We describe a scanning optical interferometer that can simultaneously perform ellipsometry measurements and thus provides a true surface pro file. This is accomplished by projecting the back focal plane of the o bjective lens onto a CCD array. The measured phase differences between the p- and s-polarization components are converted, by using a specia lly developed algorithm, to optical phase changes caused by material v ariations. The compensation process is then applied to extract the tru e profile of the object surface. Experimental results obtained with th e system are shown. (C) 1996 Optical Society of America