ELLIPSOMETRIC CHARACTERIZATION OF THIN-FILMS AND SUPERLATTICES

A description of an infrared ellipsometer for the study of surface and interface phenomena is given. The actual configuration is based on a Fourier transform spectrometer equipped with an ellipsometric attachment. The attachment is based on the so-called Beattie ellipsometer and consists essentially of two ion-etched wire grid polarizers and a mirror system of unit magnification. In order to ensure equal s and p components, the polarization of the incoming beam is set at 45° with respect to the plane of incidence. The polarization state of the reflected beam is found by measuring the intensity at different azimuthal settings of the analyser. Measurements on Pt/Al2O3 superlattices are reported and the data are compared with transfer matrix calculations. This novel technique combines both the multiplex advantage of Fourier transform spectroscopy and the phase sensitivity of ellipsometry. © 1990.