Characterization of Gadolinium oxide thin films deposited under low ambient substrate temperature using Phase Modulated Spectroscopic Ellipsometry

摘要

Advanced vacuum deposition methods and accurate determination of optical constants for thin films are highly essential in developing multilayer thin film optical devices for various laser and spectroscopic related applications. This work presents some ellipsometric characterization and analysis results on Gadolinium Oxide, a novel wide band-gap ultraviolet transmitting optical material. Using reactive electron beam evaporation technique, several samples of gadolinium oxide have been prepared at different oxygen partial pressures and rates of deposition. Then accurate information about optical constants of these films has been derived from phase modulated spectroscopic ellipsometric measurements along with a realistic physical model. It has been observed that oxygen pressure and rate of evaporation have strong influences on optical constants of these thin films. It has also been observed that samples prepared at ambient substrate conditions found to give higher band gaps, which makes this material as a potential candidate of developing multilayer UV optical coatings.