High-speed ellipsometry for the production of thin metal layers

摘要

A new ellipsometer concept is presented for which no polarizing optical components in the conventional sense and no moveable elements are necessary. With four beam splitters and four detectors, four intensities are measured. These data are needed to obtain all four Stokes parameters S$-0$/, S$-1$/, $- 2$/, S$-3$/ of the Stokes vector and so the general state of polarization of the radiation. It is shown that it is possible to determine the `optical instrument matrix' A and the `general instrument matrix' B, characterizing the whole measuring system theoretically and experimentally. The results of ex- and in-situ measurements verify the accuracy of this measuring principle. Applying suitable electronics the ellipsometer can be used as a high speed measuring device for $Psi and $Delta@. Therefore, it is especially useful for real-time ellipsometry to analyze dynamic processes at surfaces and thin films.