XPS study of high- Tc superconductor surface degradation

Abstract

Detailed quantitative XPS studies of the YBa 2Cu 3O x , and Bi 2Sr 2CaCu 2O x , high- T c superconductor (HTSC) surface layer, approximately 200 nm thick, have been carried out. Sensitivity factors both for surface and in-depth analyses with the use of ion sputtering have been determined. Atmospheric effects (aging in the presence of CO 2 and water vapour), water, alkali, moist oxygen annealing, laser irradiation and ion beam influences on the HTSC surface layer composition have been studied and possible mechanisms of the observed phenomena have been put forward.