Preparation of Superconducting Bi(Pb)-Sr-Ca-Cu-O Thick-Films on Magnesia Substrate

Abstract

Superconducting Bi(Pb)-Sr-Ca-Cu-O powders were prepared by the emulsion-drying method. The powders consisting of the low-T(c) phase (Bi(Pb)2Sr2Ca1Cu2O(y) and small amount of Ca2PbO4 were prepared by calcining under low oxygen partial pressure at 750-degrees, 800-degrees, and 830-degrees-C. These calcined powders were used to prepare thick films on single-crystal MgO(100) substrates using a screen-printing technique to study the effect of the calcination temperature and annealing procedure on the high-T(c) phase (Bi(Pb)2Sr2Ca2Cu3O(y) formation. The formation of high-T(c) phase was observed to be dependent on the calcination conditions. The high-T(c) phase formed very quickly (sintering at 840-degrees-C for 4 h), and the best films showed a sharp superconducting transition at about 105 K.