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

摘要

Films of YBa{sub}2Cu{sub}3O{sub}(7-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 2θ-scans, Ω-scans, and pole-figure analysis. A good alignment of the c-axis of the YBCO films was confirmed by the Ω-scans, in which the full width at half maximum of the YBCO(005) was 3.8°. 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{sub}c) and the critical current density (J{sub}c) of the films were determined by inductive and transport measurements, respectively. T{sub}c = 91 K with a sharp transition and J{sub}c = 2.7 × 10{sup}5A/cm{sup}2 at 77 K in zero external field were achieved on a film with 0.14-μm thickness.