Superconducting films grown in situ by the activated reactive evaporation process

The low-pressure activated reactive evaporation process was used successfully to grow superconducting YBCO thin films that were uniform in thickness, free of cracks, voids, spits, and other source-related defects, and with mirror-like surface smoothness. These are important considerations for the practical use of these materials in thin-film form. No post-deposition annealing was carried out. T sub c (0) for films on yttria-stabilized zirconia (YSZ) substrates is close to 80K, and the (001) preferred orientation was observed with higher deposition temperatures in the range 550-650 deg C. Films on Si and sapphire substrates were adversely affected by interdiffusion, showing a T sub c (0) of 56 and 72K, respectively. Graphs, photomicrographs, diffraction patterns. 14 ref.--AA