Advertisement

Properties of Y-Ba-Cu-O Thin Films Grown in-Situ at Low Temperatures by Co-Evaporation and Plasma Oxidation

  • A. L. de Lozanne
  • A. B. Berezin
  • S. Pan
  • R. M. Silver
  • E. Ogawa

Abstract

We report on the synthesis and properties of thin films of Y-Ba-Cu-O grown by co-evaporation and plasma oxidation. A differential pumping scheme is used to obtain high oxygen pressure on the substrate surface, while maintaining a low pressure at the sources and rate monitors. This results in as-deposited films which are superconducting at 73K on silicon, 68K on sapphire, and 84K on strontium titanate substrates. These are the highest transition temperatures reported on bare silicon. We present topographic and spectroscopic data obtained with a low temperature scanning tunneling microscope on films that have never been exposed to atmosphere. The films are also characterized by resistivity, critical currents, x-ray diffraction, energy and wavelength dispersive spectroscopy (EDS and WDS), inductively coupled plasma spectroscopy (ICP), SEM and TEM.

Keywords

Scanning Tunneling Microscope Thin Film Sample Main Chamber Wavelength Dispersive Spectroscopy Plasma Oxidation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    R.M. Silver, A.B. Berezin, M. Wendman, and A.L. de Lozanne, As- deposited Superconducting Y-Ba-Cu-O Thin Films on Si, Al2O3, and SrTiO3 Substrates, Appl. Phys. Lett., 52: 2174, (1988).ADSCrossRefGoogle Scholar
  2. 2.
    R.M. Silver, A.B. Berezín, E. Ogawa, and A.L. de Lozanne, Properties of In-situ Superconducting Thin Films of Y-Ba-Cu-O on Si, Al203 and SrTiO3 Substrates, Proceedings, Applied Superconductivity (1989). To appear.Google Scholar
  3. 3.
    The evaporator is a surplus Balzers BAK 550 donated by the Austin division of Motorola, Inc.Google Scholar
  4. 4.
    R.J. Spah, H.F. Hess, H.L. Stormer, A.E. White, and K.T. Short, Parameters for in situ Growth of High Te Superconducting Thin Films using an Oxygen Plasma Source, Appl. Phys. Lett., 53: 441 (1988).ADSCrossRefGoogle Scholar
  5. 5.
    N. Missert, R. Hammond, J.E. Mooij, V. Matijasevic, P. Rosenthal, T. H. Geballe, A. Kapitulnik, M. R. Beasley, S.S. Laderman, C. Lu, E. Garwin, and R. Barton, In Situ Growth of Superconducting YBaCuO Using Reactive Electron-Beam Coevaporation Proceedings, Applied Superconductivity Conf., Aug. 1984, San Francisco, CA. IEEE Trans. Magn. MAG-25, (1989). To appear.Google Scholar
  6. 6.
    S. Pan, K. W. Ng, A. L. de Lozanne, J. M. Tarascon, and L.H. Greene, Measurements of the superconducting gap of La-Sr-Cu-O with a scanning tunneling microscope, Phys. Rev. B 35: 7220 (1987).ADSCrossRefGoogle Scholar
  7. 7.
    K. W. Ng, S. Pan, and A. L. de Lozanne, Tunneling spectroscopy of High Tc oxides with a scanning tunneling microscope, Proc. 18-th Int. Conf. on Low Temp. Phys., Aug 22, 1987, Kyoto, Japan. Jap. J. Appl. Phys, 26 (supplement 26–3 ): 993 (1987).Google Scholar
  8. 8.
    A.L. de Lozanne, K.W. Ng, S. Pan, R.M. Silver and A. Berezin, Tunneling Spectroscopy of High Temperature Superconductors, Proc. Third Int. Conf. on STM, Oxford, 4–8 July, 1988. To appear in J. of Microscopy, Nov. 1988.Google Scholar
  9. 9.
    J.B. Barner and S.T. Ruggiero, Observation of the incremental charging of Ag particles by single electrons, Phys. Rev. Lett. 59: 807 (1987).ADSCrossRefGoogle Scholar
  10. 10.
    P.J.M. van Bentum, R.T.M. Smokers, and H. van Kempen, Incremental charging of single small particles, Phys. Rev. Lett. 60: 2543 (1988).ADSCrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1989

Authors and Affiliations

  • A. L. de Lozanne
    • 1
  • A. B. Berezin
    • 1
  • S. Pan
    • 1
  • R. M. Silver
    • 1
  • E. Ogawa
    • 1
  1. 1.Department of PhysicsUniversity of TexasAustinUSA

Personalised recommendations