Dependence of Superconducting Properties on Substrate Temperature in Y-Ba-Cu-O Thin Films Prepared by Magnetron Sputtering

Y-Ba-Cu-O thin films (1500–2000Å) are prepared on MgO (001) substrates at 450°C to 680°C by RF magnetron sputtering. At substrate temperatures of 580°C and above, as-grown superconducting films with high c-axis orientation, end-point Tc above 80 K and a smooth surface are obtained. As the substrate temperature decreases below 580°C, transition temperature and diffraction intensity are rapidly reduced, as is the formation of c-axis-oriented crystals with different lattice parameters.