2-MODULATOR GENERALIZED ELLIPSOMETRY - THEORY

A new ellipsometer is described that uses two photoelastic modulator-p olarizer pairs, where the photoelastic modulators are operating at dif fering resonant frequencies. The time-dependent intensity of the Light beam is extremely complicated but can be analyzed so that all element s of the sample-Mueller matrix are obtained. For a given configuration , nine of the Mueller matrix elements can be measured at ang one time; the other seven elements are accessible when the azimuthal angles of the photoelastic modulators are changed. The single-configuration meas urement is often sufficient to characterize a number of real situation s completely, such as film growth in a vacuum environment, anisotropic samples, and simple depolarization. (C) 1997 Optical Society of Ameri ca.