OXIDIZER PARTIAL-PRESSURE WINDOW FOR YBA2CU3O7-X THIN-FILM FORMATION BY METALORGANIC CHEMICAL VAPOR-DEPOSITION

We have conducted a systematic study of oxidizer partial pressure effects on both the superconducting transport properties and structural properties of YBa2Cu3O7-x (YBCO) films grown by conventional metalorganic chemical vapor deposition (MOCVD). Superconducting YBCO thin films were grown in partial N2O pressures ranging from 0.4 to 45 Torr and at substrate temperatures of 500 and 700-degrees-C. We have observed a window in oxidizer partial pressure within which YBCO thin films can be formed in the as-deposited state by the MOCVD process. A trend of increasing b-axis orientation as the oxidizer partial pressure increased was revealed by detailed x-ray diffraction. The reduction of superconducting properties for films grown at high oxidizer partial pressure might result from the lack of surface mobility. Oxygen deficiency in the films was ruled out as the cause of the degraded properties.