Advertisement

Lone-Pair Relationships and the Origin of Excited States in Amorphous Chalcogenides

  • S. R. Ovshinsky
Part of the Institute for Amorphous Studies Series book series (IASS)

Abstract

What are the chemical and structural bases of localized states in amorphous materials? In the case of tetrahedral amorphous materials, chemistry and structure can be closely related and the localized states can be clearly distinguished, for example, materials which have not reached their lowest free energy can have dangling bonds, structurally dependent voids and other kinds of vacancy defects. We classify these as extrinsic localized states which can be annealed out. When the materials are at their lowest free energy, as represented by the ideal model of Polk,(1) the localized states which remain and are the result of chemical bonding and positional disorder we consider intrinsic. In such materials, substitutional impurities can insert new extrinsic localized states and the possibility of ordinary doping exists, as shown by the work of Spear and LeComber.(2) While this is an important subject, we believe that it will follow the concepts of classical crystalline tetrahedral materials.

Keywords

Lone Pair Amorphous Material Vacancy Defect Lower Free Energy Amorphous Semiconductor 
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.
    D.E. Polk, J. Non-Cryst. Solids 5, 365 (1971).ADSCrossRefGoogle Scholar
  2. 2.
    W.E. Spear and P.G. LeCornber, Solid State Comm. 17, 1193 (1975).ADSCrossRefGoogle Scholar
  3. 3.
    M. Kastner, Phys. Rev. Lett. 28, 355 (1972).ADSCrossRefGoogle Scholar
  4. 4.
    M.H. Cohen, H. Fritzsche and S.R. Ovshinsky, Phys. Rev. Lett. 22, 1065 (1969).ADSCrossRefGoogle Scholar
  5. 5.
    S.R. Ovshinsky and K. Sapru, Proc. of 5th Intl. Conf. on Amorphous & Liquid Semiconductors, edited by J. Stuke and W. Brenig, Taylor and Francis, p. 447, 1974.Google Scholar
  6. 6.
    S.R. Ovshinsky, Proc. of 6th Intl. Conf. on Amorphous & Liquid Semiconductors, November 18–24, 1975, Leningrad, USSR.Google Scholar
  7. 7.
    S.R. Ovshinsky, 4th Intl. Congress for Reprography and Information 1975, Hannover, Germany, April 1975.Google Scholar
  8. 8.
    S.G. Bishop, U. Strom and P.C. Taylor, Phys. Rev. Lett. 34, 1346 (1975).ADSCrossRefGoogle Scholar
  9. 9.
    S.G. Bishop, U. Strom and P.C. Taylor, Phys. Rev. Lett. 36, 543 (1976).ADSCrossRefGoogle Scholar
  10. 10.
    S.R. Ovshinsky, Phys. Rev. Lett., submitted July 1975.Google Scholar
  11. 11.
    S.R. Ovshinsky, R. Flasck and H. Fritzsche, to be published.Google Scholar
  12. 12.
    H. FriUsche and M.A. Paesler, (at this conference).Google Scholar
  13. 13.
    M. Kastner, Phys. Rev. B 7, 5237 (1973).ADSCrossRefGoogle Scholar
  14. 14.
    J.P. deNeufville and U.K. Rockstad, Proc. of 5th Intl. Conf. on Amorphous & Liquid Semiconductors, edited by J. Stuke and W. Brenig, Taylor and Francis, p. 419, 1974.Google Scholar
  15. 15.
    J.P. deNeufville, R. Seguin, S.C. Moss and S.R. Ovshinsky, Proc. of 5th Intl. Conf. on Amorphous & Liquid Semiconductors, edited by J. Stuke and W. Brenig, Taylor and Francis, p. 737, 1974.Google Scholar
  16. 16.
    H. Fritzsche, J. Jap. Soc. Appl. Phys. 43 (suppl.) 32 (1974).Google Scholar
  17. 17.
    D. Emin, Electronic and Structural Properties of Amorphous Semiconductors, edited by P.G. LeCornber and J. Mort, Academic Press, p. 261, 1973.Google Scholar
  18. 18.
    N.F. Mott, E.A. Davis and R.A. Street, Phil. Mag. 31, 961 (1975).ADSCrossRefGoogle Scholar
  19. 19.
    S.R. Ovshinsky, to be published.Google Scholar

Copyright information

© Plenum Press, New York 1991

Authors and Affiliations

  • S. R. Ovshinsky
    • 1
  1. 1.Energy Conversion Devices. Inc.TroyUSA

Personalised recommendations