Degradation of thin films of YBa2Cu3O7 by annealing in air and in vacuum
The degradation of epitaxial thin films of YBa2Cu3O7 has been studied as a function of annealing temperature in air and in vacuum; some samples had an evaporated overlayer of CaF2. Degradation was monitored by the measurement of electrical properties after consecutive 30-min annealing treatments. The room-temperature resistance registered significant increases for all samples after annealing at temperatures above about 200°C; the critical current density at 77 K was degraded for annealing temperatures ≥400°C in air, and ≥200–250°C in vacuum. By annealing in oxygen at 550°C, electrical properties were restored in degraded bare YBCO samples annealed in vacuum, but not for those annealed in air.
Key wordsSuperconducting films YBa2Cu3O7 degradation of superconducting properties critical current density
Unable to display preview. Download preview PDF.
- 1.A. Mogro-Campero, L. G. Turner, A. Bogorad, and R. Herschitz,Supercond. Sci. Technol. 3, 537 (1990).Google Scholar
- 2.G. D. Loos, M. V. Pavlovskaya, and E. G. Pavlyuk,Superconductivity 5, 1302 (1992).Google Scholar
- 3.J. Bransky,J. Mater. Res. 8, 943 (1993).Google Scholar
- 4.W. A. M. Aarnink, R. P. J. Ijsselsteijn, J. Gao, A. van Silfhout, and H. Rogalla,Phys. Rev. B 45, 13002 (1992).Google Scholar
- 5.A. Mogro-Campero, L. G. Turner, A. M. Kadin, and D. S. Mallory,Appl. Phys. Lett. 60, 3310 (1992).Google Scholar
- 6.S. J. Rothman, J. L. Routbort, U. Welp, and J. E. Baker,Phys. Rev. B 44, 2326 (1991).Google Scholar
- 7.D. M. Hill, H. M. Meyers, III, J. H. Weaver, and D. L. Nelson,Appl. Phys. Lett. 53, 1657 (1988).Google Scholar
- 8.A. K. Gupta and K. V. Rao,J. Mater. Sci. 14, 1262 (1979).Google Scholar
- 9.S. B. Wong, J. J. Vajo, A. T. Hunter, and C. W. Nieh,Appl. Phys. Lett. 59, 724 (1991).Google Scholar
- 10.A. Barkatt, H. Hojaji, V. R. W. Amarakoon, and J. G. Fagan,MRS Bull., p. 45, September 1993.Google Scholar