Polarization Modulation Fourier Transform Infrared Ellipsometry of Thin Polymer Films

Abstract

Polarization modulation infrared ellipsometric spectra were collected on an FT-IR spectrometer, with the use of two linear polarizers and a photoelastic modulator. Samples consisted of thin poly(vinyl acetate) and poly(methyl methacrylate) films on gold substrates. The relative phase retardation (delta) and relative amplitude (psi) were derived from these measurements. These spectra were superior to those from static infrared ellipsometry measurements on the same samples. The thickness and optical constants of the films were calculated from the ellipsometric measurements and compared with reference optical constant spectra.