Low surface resistance Zn-doped ErBa2Cu3O7−δ thin films

Abstract: The Zn-doped ErBa2Cu3O7−δ thin films were prepared by a pulse laser deposition (PLD) on a SrTiO3, which is a lattice, matched substrate. The various contents of the Zn-doped ErBa2Cu3O7−δ ceramics were used as the targets. All the films were grown at 750°C under an oxygen pressure of 400mTorr. From the X-ray diffraction (XRD) patterns, only the 00 l reflections were observed. Surface resistance (R S) measurement revealed that the ErBa2(Cu0.9Zn0.1)3O7−δ films showed a superconducting transition temperature (T C) below 70K. The R S value of the ErBa2(Cu0.997Zn0.003)3O7−δ films and that of the ErBa2(Cu0.995Zn0.005)3O7−δ films was lower than that of the ErBa2Cu3O7−δ films for wide temperature region of 10–90K. From the observation of the atomic force microscopy (AFM), a lot of pores were observed in the surface of the Zn-doped ErBa2Cu3O7−δ films, which showed a low R S. [Copyright &y& Elsevier]