DETERMINATION OF OPTICAL-CONSTANTS OF Y2O3 FILMS FROM REFLECTANCE AND TRANSMITTANCE DATA USING DIFFERENT APPROACHES

The optical constants of thin Y2O3 dielectric films have been determined by two methods, one of which involves both reflectance and transmittance spectra whereas the other is based on transmittance spectra only. The first method is more elaborate because the interference effects have been considered. By careful adjustment of the mean thickness of the films, continuous dispersive curves of the refractive index n and absorption coefficient alpha have been determined. The second method utilses the envelope of interference maxima and minima of transmittance spectra. The method is straightforward and simple. The magnitude of n at an wavelength of 700 nm is found to be 1.53 and 1.66 by the two methods respectively.