A high-resolution synchrotron X-ray scattering study of the surface and interface structures of YBa2Cu3Ox thin films

Abstract A highly oriented YBa 2 Cu 3 O x thin-film superconductor (>1500 A) grown on SrTiO 3 substrate by off-axis laser deposition has been studied by high-resolution X-ray scattering using synchrotron radiation. Oscillation fringes were found in the X-ray scattered intensity profiles of both the glancing incident X-ray reflectivity and the crystal-truncation-rod scans of the low-index Bragg reflections. These fringes demonstrate the excellent coherency between the surface and interface, and the superior homogeneity of the film thickness. A thin disordered layer was revealed on top of the YBa 2 Cu 3 O x film by X-ray reflectivity. The surface and the interface were found not to be perfectly aligned along either the crystallographic axes of the substrate nor the film.