On the New Substrate Materials for High-Tc Superconducting Ba-Y-Cu-O Thin Films

In order to check whether BaAl2O4, BaZrO3, Ba2SiO4 and BaF2 compounds are adequate as new substrate materials for high-T c superconducting Ba-Y-Cu-O thin films or not, the reactions of these compounds with quenched BaYCuO (nominal composition: Ba2YCu3O7-x ) at 900°C were examined using X-ray diffraction analyses and measurements of superconducting properties. It was found that BaZrO3, Ba2SiO4 and BaF2 did not react strongly with the quenched BaYCuO and were excellent candidates as new substrate materials.