LOW-TEMPERATURE ANNEALING EFFECT ON BI-SR-CA-CU-O THIN-FILMS PREPARED BY LAYER-BY-LAYER DEPOSITION

Thin films of Bi-Sr-Ca-Cu-O superconductors are prepared by layer-by-layer deposition using automatically controlled shutters. The films are deposited by microwave-discharged plasma assisted reactive evaporation. The thin films of the 2201 phase, 2212 phase, and 2223 phase are obtained in accordance with respective shuttering sequences. As-grown films do not show superconductivity, because of excess oxygen content. Superconducting thin films of the 2212 phase with zero resistance at 40 K are obtained by low-temperature annealing at 550-degrees-C in an oxygen partial pressure of 0.1 atm.