Measurements of optical parameters of antimony trisulphide films

Abstract

In the course of a systematic investigation of thin absorbing films, the optical constants of antimony trisulphide (Sb2S3) films evaporated on glass were determined for a fairly wide range of thicknesses. The measurements were performed at the wavelength ofλNa=5893 A by the ellipsometric method on the one hand and by intensity measurements of reflected and transmitted light on the other. Independently, the film thickness was measured by the Tolansky interference method. In this way it was possible in both cases to determine both the refractive index of the film and the absorption index using a method currently employed with transparent dielectric films: that of the interpolation of tabulated values. The results of measurements revealed a change in both the refractive and the absorption index with film thickness. The ellipsometric and the intensity measurements gave results in very close agreement.