Inclined substrate pulsed laser deposition of YBCO thin films on polycrystalline AG substrates

Films of YBa2Cu3O7-x (YBCO) with c-axis orientation were directly deposited on nontextured silver substrates by inclined substrate pulsed laser ablation. The structure of the YBCO films was characterized by X-ray diffraction 2theta-scans, Omega-scans, and pole-figure analysis. A good alignment of the c-axis of the YBCO films was confirmed by the Omega-scans, in which the full width at half maximum of the YBCO(005) was 3.8degrees. A sharp interface between the YBCO film and Ag substrate was observed by transmission electron microscopy. The surface morphology of the film, examined by scanning electron microscopy, reflected the recrystallization of the Ag substrate. Raman spectroscopy was used to evaluate the quality of the YBCO films. The superconducting transition temperature (T-c) and the critical current density (J(c)) of the films were determined by inductive and transport measurements, respectively. T-c = 91 K with a sharp transition and J(o) = 2.7 x 10(5)A/cm(2) at 77 K in zero external field were achieved on a film with 0.14-mum thickness.