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 YBa₂Cu₃O_7-δ (YBCO) thin-film growth. The desired (001) YSZ texture is obtained at 1.0 mTorr oxygen pressure and 70 °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 T_c(R=0)=92 K and J_c (77 K, B=0 T)=6×10⁵ A/cm² and J_c (77 K, 0.4 T)=8×10⁴ 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.