PVD growth and characterization of YBCO thin films on polycrystalline alumina substrates: phase separation

2000-11-01
Ozenbas, MA
Gungoren, T
In this study, high T-c superconducting thin films of Y-Ba-Cu-O system have been prepared onto polycrystalline alpha -Al2O3 substrates by resistive evaporation of YF3, BaF2, and Cu powders and a subsequent multi-stage annealing. In the deposition process, two different methods were used: mixed-powder method and sequential-deposition method. The best quality films were achieved on alpha -Al2O3 substrates by using sequential-deposition technique with offset critical transition temperature of 80.6 K. Sequential deposition method seems to reduce film-substrate reactions on alpha -Al2O3 substrates, probably due in part to the prevention of phase separation.

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Citation Formats
M. Ozenbas and T. Gungoren, “PVD growth and characterization of YBCO thin films on polycrystalline alumina substrates: phase separation,” PHYSICA C, pp. 2363–2364, 2000, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65420.