Laser deposition of biaxially textured yttria-stabilized zirconia buffer layers on polycrystalline metallic alloys for high critical current Y-Ba-Cu-O thin films

Pulsed laser deposition of yttria-stabilized zirconia (YSZ) layers on polycrystalline metallic alloy substrates is used to produce an intermediate layer for YBa2Cu3O7-δ (YBCO) thin-film growth. The desired (001) YSZ texture is obtained at 1.0 mTorr oxygen pressure and 70 degree C. Significant improvement in (001) texturing is demonstrated by using an ion beam to assist growth. Argon-ion-assisted growth produces layers with alignment of the in-plane crystal axes in addition to the (001)-normal texture. Highly c-axis-oriented biaxially aligned YBCO thin films can be deposited on these layers, with Tc(R=0)=92 K and Jc (77 K, B=0 T)=6x105 A/cm2 and Jc (77 K, 0.4 T)=8x104 A/cm2. With further improvement of the YSZ texture, the YBCO current-carrying capacity of films on polycrystalline metallic alloys may approach that of films on single-crystal substrates