In-Situ Real-Time Ellipsometry Study of Dynamic Processes of YBa2Cu3O7−x Thin Films

Abstract

ABSTRACTThe optical absorption peak at 4. leV associated with oxygen deficiency in YBa2Cu3O7−x thin films was monitored by spectroscopic ellipsometry (SE) in real time during the growth process. Two regimes dominated by oxygen out- and in-diffusion have been observed during deposition by ion beam sputtering at 700°C.The effect of oxygen partial pressure during the post-deposition cooling process on the oxidation of deposited films has also been investigated. The thermodynamic stability of the grown films was examined by real time SE during post annealing process. In-situ SE measurements have been performed to obtain the dielectric function of oxygen deficient YBa2Cu3O6 films in the temperature range from 27°C to 700°C. It has been demonstrated that real time SE is a sensitive and useful technique for in-situ diagnostics of the dynamics of YBa2Cu3O7−x thin film processes.