YBa/sub 2/Cu/sub 3/O/sub 7/ thin films on nanocrystalline diamond films for HTSC bolometer

Superconducting YBa/sub 2/Cu/sub 3/O/sub 7-x/ films on nanocrystalline diamond thin films have been fabricated. A composite buffer layer system consisting of diamond/Si/sub 3/N/sub 4//YSZ/YBCO was explored for this purpose. The as-deposited YBCO films were superconducting with T/sub c/ of approximately 84 K and a relatively narrow transition width of approximately 8 K. Scanning electron microscope cross sections of the films showed very sharp interfaces between diamond/Si/sub 3/N/sub 4/ and between Si/sub 3/N/sub 4//YSZ. The deposited YBCO film has a surface roughness of approximately 1000 AA, which is suitable for high-temperature superconductive (HTSC) bolometer fabrication. It was also found that preannealing of the nanocrystalline diamond thin films at high temperature was very important for obtaining high-quality YBCO films.<<ETX>>