Effect of Er/Y addition on the growth and superconductivity of Bi2212 films

In order to increase the critical current density of Bi2212 superconducting films to broaden their application areas. A series of Bi(2)Sr(2)CaCu(2)O(8+δ)–xRE(2)O(3) (RE = Er/Y) (x = 0, 0.04, 0.08, 0.12, 0.16, 0.20) thin films were prepared by the sol–gel method. The structure, morphology and superconductivity of the RE(2)O(3) doping films were characterized in detail. The effect of RE(2)O(3) on the superconductivity of Bi2212 superconducting films was investigated. It was shown that the Bi2212 films were (00l) epitaxially grown. The in-plane orientation relationship between the Bi2212–xRE(2)O(3) and the SrTiO(3) was Bi2212[100](001)//SrTiO(3)[011](100). The grain size in the out-of-plane direction of Bi2212 tends to increase with the amount of RE(2)O(3) doping. Doping with RE(2)O(3) had no significant effect on the anisotropy of Bi2212 crystal growth, but inhibited the agglomerative growth of the precipitated phase on the surface to a certain extent. Furthermore, the conclusion was that the superconducting transition temperature (T(c,onset)) was almost unaffected, while the zero resistance transition temperature (T(c,zero)) continued to decrease with increasing doping level. The thin film samples Er2 (x = 0.04) and Y3 (x = 0.08) exhibited the best current-carrying capacity in magnetic fields.