Preparation of Y-Ba-Cu-O superconducting thin films using BaF2 as a buffer layer

Abstract

Thin films of barium fluoride (BaF2 ), used as a buffer layer between the substrate and the superconducting films, dramatically improve the properties of Y-Ba-Cu-O (YBCO) superconducting films deposited by metalorganic chemical vapor deposition on yttrium-stabilized zirconia (YSZ) substrates. For the as-deposited films at a substrate temperature of 780 °C, the observed transition temperature Tc of 80 K on the BaF2 /YSZ structure represents the highest value reported to date. By using BaF2 buffer layers, superconducting films formed by using a paste of the YBCO powder and a binder, on BaF2 /Si provided a Tc of 80 K.