The epitaxial growth of BaSnO3 buffer layer on IBAD-MgO template and its effects on GdBa2Cu3O7−δ film: A preliminary study

Abstract We report a successful fabrication of c -axis oriented GdBa 2 Cu 3 O 7− δ (GdBCO) films on the BaSnO 3 (BSO) buffer layers on ion-beam assisted deposition (IBAD)-MgO template by pulsed-laser deposition (PLD). The (0 0  l ) growth and in-plane textures of BSO buffer layers were found sensitive to the substrate temperature ( T s ). With increasing the BSO layer thickness up to ∼165 nm, in-plane texture (Δ ϕ  ∼ 6.2°) of BSO layers was almost unaltered while completely c -axis oriented BSO layers were obtainable from samples with the thickness below ∼45 nm. On the BSO buffer layers showing in-plane texture of 6.2° and RMS surface roughness of ∼8.6 nm, GdBCO films were deposited at 780–800 °C. All GdBCO films exhibited Δ ϕ values of 4.6–4.7°, T c,zero of ∼91 K, and critical current density ( J c ) over 1 MA/cm 2 at 77 K in a self-field. The highest J c value of 1.82 MA/cm 2 ( I c of 51 A/cm-width) was achieved from the GdBCO film deposited at T s of 790 °C. These results support that BSO can be a promising buffer layer on the IBAD-MgO template for obtaining high- J c GdBCO coated conductors.