Properties of superconducting Nd1+xBa2-xCu3O7-delta thin films deposited by dc magnetron sputtering

We report the superconducting properties of Nd1+xBa2-xCu3O7-delta thin film s deposited by dc magnetron sputtering from stoichiometric Nd1Ba2Cu3O7-delt a and off-stoichiometric Nd1.12Ba1.88Cu3O7-delta targets. Highly epitaxial c-axis oriented samples with thicknesses ranging from 5 to 100 nm were obta ined on SrTiO3 (100) substrates from both targets. A suppression of screw-d islocation mediated growth for off-stoichiometric films is observed by STM, resulting in smooth surfaces with roughness of 2-3 nm on a 1 mu m(2) area. The effects of the deposition conditions on the structural and superconduc ting properties are investigated and discussed in relation to the Nd-Ba sub stitution in the Nd1+xBa2-xCu3O7-delta system. (C) 1998 American Institute of Physics. [S0003-6951(98)04131-X].