Charged Fraction of 5 keV to 150 keV Hydrogen Atoms after Emergence from Different Metal Surfaces

  • R. Behrisch
  • W. Eckstein
  • P. Meischner
  • B. M. U. Scherzer
  • H. Verbeek


The charged fraction of hydrogen atoms backseattered from Be, V, Cu, Nb, Mo and Ta surfaces has been measured for energies between 5 keV and 150 keV and a wide range of angles of emergency. Hydrogen particles with energies above 20 keV are counted and energy analysed by a surface barrier detector. Charged particles are separated from the neutrals by means of electrical deflection plates between target and detector. Neutrals with energies below 20 keV are partly ionized in a calibrated gas stripping cell. They are energy analysed in a subsequent electrostatic spectrometer and counted by a channeltron multiplier. The backscattered ions were recorded with no gas in the stripping cell. Only small differences are found for the charged fraction for different materials as long as the surface is covered by a layer of adsorbed impurities. There is, however, for most materials a change in the charged fraction due to annealing the target. For emergence energies above ~ 40 keV it is lower than for unannealed targets. An observed dependence of the charged fraction on the angle of emergence was generally just slightly above the experimental error.

The measured results are compared with theoretical curves of Zaidins, Trubnikov et al., and Brandt and Sizmann. The best agreement is found with values given by Zaidins. The peculiarities observed at annealed surfaces are not predicted by theory.


Charged Particle Charge State Annealed Surface Charged Fraction Target Chamber 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. [1]
    S. K. Allison, Rev. Mod. Phys. 30, 1137 (1958).ADSCrossRefGoogle Scholar
  2. [2]
    K. H. Berkner, I. Bornstein, R. V. Pyle, J. W. Stearns, Phys. Rev. A 6, 278 (1972).ADSCrossRefGoogle Scholar
  3. [3]
    T. M. Buck, G. H. Wheatley, L. C. Feldman, Surf. Sci. 15, 345 (1973).CrossRefGoogle Scholar
  4. [4]
    See: Nucl. Instr. Meth. 110, 1–522 (1973).Google Scholar
  5. [5]
    E. S. Mashkova and V. A. Molchanov, Rad. Eff. 16, 143–187 (1972).CrossRefGoogle Scholar
  6. [6]
    W. Brandt and R. Sizmann, Phys. Lett. 37A, 115 (1971).ADSGoogle Scholar
  7. [7]
    C. Rau and R. Sizmann, Phys. Lett. 43A, 317 (1973).ADSGoogle Scholar
  8. [8]
    R. Behrisch, W. Heiland, 6th Symp. on Fusion Technology, Aachen, 1970.Google Scholar
  9. [9]
    T. Hall, Phys. Rev. 79, 504 (1950).ADSCrossRefGoogle Scholar
  10. [10]
    C. S. Zaidins, Ph. D. Thesis, Appendix 1, California Institute of Technology 1967;Google Scholar
  11. [10a]
    see also: J. B. Marion and F. C. Young, Nucl. Radiation Analysis, North Holland 1968, p. 36.Google Scholar
  12. [11]
    M. E. Ebel, Phys. Rev. Lett. 24, 1395 (1970).ADSCrossRefGoogle Scholar
  13. [12]
    N. V. Federenko, Sov. Phys. Techn. Phys. 15, 1947 (1971).ADSGoogle Scholar
  14. [13]
    H. Tawara and A. Russek, Rev. Mod. Phys. 45, 178 (1973).ADSCrossRefGoogle Scholar
  15. [14]
    B. A. Trubnikov and Yu. N. Yavlinski, Sov. Phys. JETP 25 1089 (1967).ADSGoogle Scholar
  16. [15]
    Yu. N. Yavlinski, B. A. Trubnikov, V. F. Elesin, Bull. Acad. Sci., USSR Phys. Sov. 30, 1996 (1968).Google Scholar
  17. [16]
    J. A. Phillips, Phys. Rev. 97, 404 (1955).ADSCrossRefGoogle Scholar
  18. [17]
    S. Rubin, Nucl. Instr. Meth. 5, 177 (1959).CrossRefGoogle Scholar
  19. [18]
    E. Bøgh, Can. J. Phys. 46, 653 (1968).ADSCrossRefGoogle Scholar
  20. [19]
    R. Behrisch, Thesis, Techn. Univ. of Munich (1968)Google Scholar
  21. [20]
    W. Eckstein and H. Verbeek, IPP Report 9/7, 1972 and Vacuum 23, 159 (1973).Google Scholar
  22. [21]
    R. Behrisch, Vak. Techn. 10, 250 (1967).Google Scholar
  23. [22]
    A. Egidi, R. Marconero, G. Pizella, Rev. Sci. Instr. 40, 88 (1969).ADSCrossRefGoogle Scholar
  24. [23]
    H. Schmidl, IPP Report 9/3 (1971).Google Scholar
  25. [24]
    B. M. U. Scherzer, Thesis, Techn. Univ. of Munich (1969).Google Scholar
  26. [25]
    See for example: M. A. Nicolet, J. W. Mayer, I. V. Mitchell, Science 177, 481 (1972).CrossRefGoogle Scholar
  27. [26]
    R. Behrisch, B. M. U. Scherzer, H. Schulze, Rad. Eff. 13, 33 (1972).CrossRefGoogle Scholar
  28. [27]
    K. O. Groeneveld and M. Kaminsky, Bull. Am. Phys. Soc. 14, 1246 (1969) and private communication.Google Scholar
  29. [28]
    R. Sizmann, private communication.Google Scholar
  30. [29]
    H. Schäffler, Thesis, Technical University of Munich (1973).Google Scholar

Copyright information

© Springer Science+Business Media New York 1975

Authors and Affiliations

  • R. Behrisch
    • 1
  • W. Eckstein
    • 1
  • P. Meischner
    • 1
  • B. M. U. Scherzer
    • 1
  • H. Verbeek
    • 1
  1. 1.EURATOM AssociationMax-Planck-Institut für PlasmaphysikGarchingGermany

Personalised recommendations