Characterization of Nd2−xCexCuO4±δ (x = 0 and 0.15) Ultrathin Films Grown by DC Sputtering Technique

High-temperature superconductivity in cuprate materials is achieved by hole or electron doping of the parent Mott insulator. In this paper, electron-doped Nd 2−x Ce x CuO 4±δ films with different content of cerium have been grown on (010) SrTiO 3 (TiO 2 ) substrates through a dc sputtering technique. Since the normal conducting films can be obtained by controlling the oxygen content inside the crystalline structure by means of appropriate annealing procedures (that allow a reduction process), different as-grown nonsuperconducting films have been obtained. The samples have been thermally treated ex-situ at different temperatures and atmospheres in order to investigate the effects of different content of oxygen on the films properties. The results of the composition analysis, of the structural characterization and of the electric transport measurements on samples with a Ce fraction of 0 and 0.15 will be discussed.