Advertisement

Methods to Reduce Contamination in Targets Prepared by Vacuum Deposition

  • G. E. Thomas
  • S. K. Lam
  • R. W. Nielsen

Abstract

For some time, both the experimenters and we target makers have been concerned about the source of impurities which were found from experimental data obtained using targets prepared by vacuum vapor deposition. These impurities may arise from the process of producing the target, the separated isotope used in the evaporation, or contaminants introduced during the experiment. Some impurities such as carbon, oxygen and nitrogen are likely to be introduced into the target during evaporation, as a result of residual gases and contaminants, such as diffusion pump oil, present in the vacuum system. The present study was initiated to determine the source of impurities found in our targets. We would like to mention some of the experimenters who were kind enough to cooperate with us by bringing to our attention these impurities whenever they found them and, in addition, letting us use some of their data: D. F. Geesaman, W. Henning, M. S. Kaminsky, D. G. Kovar, W. Kutschera, G. C. Morrison, M. Paul, and S. J. Sanders.

Keywords

Diffusion Pump Evaporation Time Oxygen Contamination Aluminum Target Magnesium Isotope 
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).
    Varian/NRC 3117 vacuum coating system manufactured by Varian, Palo Alto Vacuum Division, 611 Hansen Way, Palo Alto, CA 94303.Google Scholar
  2. (2).
    Kronos thickness monitor, Model QM321. Distributed by Veeco Instruments Inc., Terminal Drive, Plainview, NY 11803.Google Scholar
  3. (3).
    S. Deutschmann, Scientific Foundations of Vacuum Technique, second edition, edited by J. M. Lafferty (John Wiley and Sons, Inc., NY, 1962), p. 14.Google Scholar
  4. (4).
    G. C. Morrison, D. F. Geesaman, W. Henning, and D. G. Kovar, Private communication.Google Scholar
  5. (5).
    Eagle Picher Industries, Inc., Electronics Division, Miami, OK 74354.Google Scholar
  6. (6).
    S. J. Sanders, M. Paul, J. Cseh, D. F. Geesaman, W. Henning, D. G. Kovar, C. Olmer, and J. P. Schiffer, Resonant Behavior of the 24Mg(16O, 12C)28Si Reaction, to be published.Google Scholar
  7. (7).
    F. J. Karasek, Rolling of Evaporated Magnesium Isotopes, published in these proceedings.Google Scholar
  8. (8).
    M. S. Kaminsky and S. K. Lam, Private communication.Google Scholar
  9. (9).
    S. K. Lam and M. S. Kaminsky, Private communication.Google Scholar

Copyright information

© Plenum Press, New York 1981

Authors and Affiliations

  • G. E. Thomas
    • 1
  • S. K. Lam
    • 1
  • R. W. Nielsen
    • 1
  1. 1.Argonne National LaboratoryArgonneUSA

Personalised recommendations