In-Situ Surface Observation of C-Axis Oriented YBa2Cu3O7−x Thin Films by Leed, XPS and ISS

Abstract

1. AbstractIn an ultra-high vacuum equipment, YBa2CU3O7−x (YBCO) thin films were deposited by the ozone-assisted co-evaporation method and their surfaces were investigated by LEED, XPS and ISS without breaking the vacuum. A LEED pattern was observed for the first time at an as-deposited surface. A clean, crystalline and superconducting surface was preserved to the top of the film. Only Cu atoms were detected at the first monolayer by ISS, suggesting that clean surfaces are stabilized by Cu-O layers.