Formation of Superconducting Phases in Electron-Doped Nd_1.85Ce_0.15CuO_4-y

The effect of annealing process in flowing nitrogen on the formation of super-conducting phases in Nd_1.85Ce_0.15CuO_4-y has been investigated. Two super-conductingphases with onset temperature T_cons of about 15 and 25K might be formed when the samples were annealed at various temperatures ranging from
850°C to 870°C and from 880°C to 920°C, respectively. The dependence of T_cons on the annealing temperature was reported.