High T_c YBa₂Cu₃O_7-x thin films on Si substrates by dc magnetron sputtering from a stoichiometric oxide target

Thin films of YBa2Cu3O7-x were deposited on Si substrates at 600-700°C by dc magnetron sputtering from a stoichiometric oxide target. Resistivity measurement results indicate that these films are superconducting with a zero resistance Tc as high as 76 K, without further high-temperature post-annealing treatments. These films give both core and valence-band x-ray photoemission, and x-ray diffraction spectra similar to those for superconducting films prepared with a high-temperature post-annealing step. No significant diffusion of Si from the substrate into the film was detected for the films deposited at 650°C or lower, according to depth profiles obtained using secondary ion mass spectrometry.