Structural and electrical properties of biaxially textured YBa2Cu3O7-x thin filmson buffered Ni-based alloy substrates

摘要

Oxide high-T(sub c) superconducting wires and tapes with high critical currentdensity (J(sub c)) are essential in future electrical power applications. Recently, YBa(sub 2)Cu(sub 3)O(sub 7(minus)x) (YBCO) thin films grown on Ni-based alloy tapes have attracted intense interest because of their promise for these applications. In order to achieve high J(sub c), buffer layers are necessary for fabricating biaxially aligned YBCO thin films. In our studies, yttria-stabilized zirconia (YSZ) layers were deposited on Ni-based alloy substrate by ion-beam assisted deposition, and CeO(sub 2) buffer layers were subsequently deposited on the YSZ layer by pulsed laser deposition (PLD) or electron beam evaporation. In addition, MgO layers were deposited on Ni-based alloy substrates by inclined substrate deposition. Finally, biaxially textured YBCO thin films were deposited on these buffered metallic substrates by PLD under optimized conditions. The orientation and in-plane textures of YBCO and the buffer layers were characterized by X-ray diffraction (Theta)/2(Theta) scan, (phi)-scan, and pole figure analysis. The superconductive transition features were examined by measuring inductive T(sub c) and transport J(sub c).