- Physical Review Journals
All JournalsPhysics Magazine
Access Provided by Xinjiang University

Physical Review B

Export citation

Export citation

Choose format for download:

Download Citation
  • Access by Xinjiang University

Valence- and conduction-band structure of the sapphire (11¯02) surface

W. J. Gignac and R. Stanley Williams

Steven P. Kowalczyk

  • Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90024

  • Rockwell International Corporation, Microelectronics Research and Development Center, Thousand Oaks, California 91360

PDF

Phys. Rev. B 32, 1237 – Published 15 July, 1985

DOI: https://doi.org/10.1103/PhysRevB.32.1237

Abstract

X-ray photoelectron (XPS) and electron-energy-loss spectroscopies have been employed to investigate the valence- and conduction-band densities of states of the sapphire (11¯02) surface. The photoemission spectrum of the valence-band region has been adjusted to remove cross-section effects and compared to the recent theoretical density of states calculated by Ciraci and Batra. The energy-loss data have been used to determine the bulk-plasmon energy of sapphire, 24.0±0.3 eV, as well as the locations of eight regions of high conduction-band–state density within 20 eV above the conduction-band minimum. One of these regions is an empty surface state 4.0 eV below the conduction-band minimum. Several high-binding-energy satellites in the XPS core-level spectra are reported and interpreted in terms of energy losses to plasmons and interband transitions.

View figure in article

References (55)

  1. G. H. C. Freeman, Brit. J. Appl. Phys. 16, 927 (1965).
  2. G. Stephan, J. C. Lemonnier and S. Robin, J. Opt. Soc. Am. 57, 486 (1967).
  3. E. T. Arakawa and M. W. Williams, J. Phys. Chem. Solids 29, 735 (1968).
  4. C. J. Powell and J. B. Swan, Phys. Rev. 118, 640 (1960).
  5. N. Swanson, Phys. Rev. 165, 1067 (1968).
  6. L. B. Leder, Phys. Rev. 103, 1721 (1956).
  7. E. R. Il'mas and A. I. Kuznetsov, Fiz. Tverd. Tela (Leningrad) 14, 1464 (1972) [Sov. Phys.—Solid State 14, 1255 (1972)].
  8. E. Loh, Solid State Commun. 2, 269 (1964).
  9. M. H. Reilly, J. Phys. Chem. Solids 31, 1041 (1970).
  10. F. C. Douglas, Ph.D. thesis, University of Connecticut, 1970 (unpublished).
  11. J. A. Tossel, J. Am. Chem. Soc. 97, 4840 (1975).
  12. J. A. Tossel, J. Phys. Chem. Solids 36, 1273 (1975).
  13. K. L. Brower, J. Vac. Sci. Technol. 12, 458 (1975).
  14. R. A. Evarestov, A. N. Ermoshkin and V. A. Lovchikov, Phys. Status Solidi B 99, 387 (1980).
  15. I. P. Batra, J. Phys. C 15, 5399 (1982).
  16. S. Ciraci and I. P. Batra, Phys. Rev. B 28, 982 (1983).
  17. A. Balzarotti and A. Bianconi, Phys. Status Solidi B 76, 689 (1976).
  18. S. P. Kowalczyk, F. R. McFeely, L. Ley, V. T. Gritsyna and D. A. Shirley, Solid State Commun. 23, 161 (1977).
  19. K. Codling and R. P. Madden, Phys. Rev. 167, 587 (1968).
  20. A. Balzarotti, A. Bianconi, E. Burattini, M. Grandolfo, R. Habel and M. Piacentini, Phys. Status Solidi 63, 77 (1974).
  21. A. Balzarotti, F. Antonangeli, R. Girlanda and G. Martino, Phys. Rev. B 29, 5903 (1984).
  22. A. Balzarotti, F. Antonangeli, R. Girlanda and G. Martino, Solid State Commun. 44, 275 (1982).
  23. V. A. Fomichev, Fiz. Tverd. Tela (Leningrad) 10, 763 (1968) [Sov. Phys.—Solid State 8, 2312 (1967)].
  24. I. A. Brytov and Y. N. Romashchenko, Fiz. Tverd. Tela (Leningrad) 20, 2843 (1978) [Sov. Phys.—Solid State 20, 384 (1978)].
  25. C. G. Dodd and G. L. Glen, J. Appl. Phys. 39, 5377 (1968); J. Am. Ceram. Soc. 53, 322 (1970).
  26. D. W. Fischer, Adv. X-Ray Anal. 13, 159 (1970).
  27. C. Benndorf, G. Keller, H. Seidel and F. Thieme, Surf. Sci. 67, 589 (1977).
  28. J. Olivier and R. Poirier, Surf. Sci. 105, 347 (1981).
  29. I. P. Batra and L. Kleinman, J. Electron Spectrosc. 33, 175 (1984).
  30. A. Bianconi, R. Z. Bachrach and S. A. Flodstrom, Phys. Rev. B 19, 3879 (1979); Solid State Commun. 24, 539 (1977).
  31. A. Bianconi, Surf. Sci. 89, 41 (1979).
  32. alpha-A2_3_, also known as corundum, has rhombohedral symmetry. However, it is usually refered to hexagonal axes for simplicity. See, for example, R. W. G. Wyckoff, in Crystal Structures II, 2nd ed. (Wiley, New York, 1964), or R. Nolder and I. Cadoff, Trans. Metall. Soc. AIME 233, 549 (1965).
  33. C. C. Chang, J. Appl. Phys. 39, 5570 (1968).
  34. C. C. Chang, in The Structure and Chemistry of Solid Surfaces, edited by G. A. Somorjai (Wiley, New York, 1969), article 77-1.
  35. C. C. Chang, J. Vac. Sci. Technol. 8, 500 (1971).
  36. J. C. Bean, Appl. Phys. Lett. 36, 741 (1980).
  37. For a discussion of EELS theory and experiment, see H. Froitzheim, in Electronic Spectroscopy for Surface Analysis, edited by H. Ibach (Springer, Berlin, 1977), p. 205.
  38. J. E. Rowe and H. Ibach, Phys. Rev. Lett. 31, 102 (1973).
  39. H. Ibach and J. E. Rowe, Phys. Rev. B 9, 1951 (1974).
  40. J. H. Scofield, J. Electron. Spectrosc. 8, 129 (1976).
  41. S. P. Kowalczyk, Ph.D. thesis, University of California, 1976 (unpublished).
  42. M. P. Seah and W. A. Dench, Surf. Interface Anal. 1, 2 (1979).
  43. R. S. Williams, S. P. Kowalczyk, P. S. Wehner, G. Apai, J. Stöhr and D. A. Shirley, J. Electron Spectrosc. Relat. Phenom. 12, 477 (1977).
  44. H. Raether, in Excitation of Plasmons and Interband Transitions by Electrons (Springer, Berlin, 1980).
  45. B. D. Evans, H. D. Hendricks, F. D. Bazzarre, and J. M. Bunch, in Ion Implantation in Semiconductors, edited by F. Chernow, J. A. Borders, and D. K. Brice (Plenum, New York, 1977), p. 265.
  46. K. H. Lee and J. H. Crawford, Jr., , Phys. Rev. B 19, 3217 (1979).
  47. B. D. Evans and M. Stapelbroek, J. Nucl. Mater. 85 - 86, 497 (1979).
  48. H. H. Tippins, Phys. Rev. B 1, 126 (1970).
  49. P. W. Levy, Phys. Rev. 123, 1226 (1961).
  50. E. W. J. Mitchell, J. D. Rigden and P. D. Towsend, Philos. Mag. 5, 1013 (1960).
  51. K. H. Lee and J. H. Crawford, Jr., , Appl. Phys. Lett. 33, 273 (1978).
  52. E. Harari and B. S. H. Royce, Appl. Phys. Lett. 22, 106 (1973).
  53. V. E. Henrich, G. Dresselhaus and H. J. Zeiger, Phys. Rev. Lett. 36, 158 (1976).
  54. C. E. Moore, Atomic Energy Levels, U.S. National Bureau of Standards Circular No. 467 (U.S. GPO, Washington, D.C., 1949), Vol. 1.
  55. W. H. Strehlow and E. L. Cook, J. Phys. Chem. Ref. Data 2, 163 (1973).

Outline

Information

Phys. Rev. B 32, 1237– Published 15 July, 1985
  • Received 16 July 1984

© 1985 American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation