High <i>T</i> <i>c</i> Y-Ba-Cu-O thin films prepared by <i>i</i> <i>n</i> <i>s</i> <i>i</i> <i>t</i> <i>u</i> low-temperature codeposition of Y, BaF2, and Cu on α-Al2O3 substrates

Abstract

Thin Y-Ba-CU-O films were prepared in-situ by low-temperature codeposition on Al2O3 substrates. The temperatures during preparation did not exceed 600 °C. As a source of Ba the BaF2 was used. The zero resistance Tc values were higher than 84 K, Jc =4×104 A/cm2 at 4.2 K/OT. The Auger electron spectroscopy analysis has shown almost a homogeneous distribution of the film components throughout the film thickness. X-ray diffraction revealed the presence of unoriented 1-2-3 phase besides BaF2 and CuO and, one undefined phase, which might be oxyfluoride compound.