Journal of Materials Science

, Volume 15, Issue 11, pp 2720–2728 | Cite as

Formation of metastable solid solutions in the Pb-Ge system

  • Dilshad Akhtar
  • T. C. Goel
  • V. D. Vankar
  • K. L. Chopra
Papers

Abstract

The formation and decomposition behaviours of metastable solid solutions in liquid-quenched and vapour-quenched Pb-Ge alloys were studied using X-ray diffraction, transmission electron microscopy (TEM), differential thermal analysis (DTA) and resistance measurement techniques. It is shown that the Pb-rich fcc phase can retain upto about 13 at% Ge on liquid-quenching and upto about 5 at% Ge on vapour-quenching. Decomposition of the Pb-rich fcc phase occurs in the temperature range 220 to 300° C and it is a temperature dependent nucleation and growth phenomenon. Upto about 7.5 at% Pb can be retained in Ge-rich compositions in an amorphous Ge matrix on vapour-quenching but there is no detectable solubility of Pb in crystalline Ge retained by liquid-quenching. On heating, the amorphous Ge-Pb films crystallize to a Ge-rich solid solution which decomposes to equilibrium constituents at higher temperatures. Stability of amorphous Ge-Pb films decreases on increasing metal concentration.

Keywords

Polymer Microscopy Electron Microscopy Transmission Electron Microscopy Solid Solution 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    K. L. Chopra, “Thin Film Phenomena” (McGraw-Hill, N.Y., 1969).Google Scholar
  2. 2.
    T. R. Anantharaman and C. Suryanarayana J. Mater. Sci. 6 (1971) 1111.Google Scholar
  3. 3.
    Dilshad Akhtar, V. D. Vankar, T. C. Goel and K. L. Chopra, ibid. 14 (1979) 983.Google Scholar
  4. 4.
    Idem, ibid. 14 (1979) 988.Google Scholar
  5. 5.
    Idem, Thin Solid Films 58 (1979) 327.Google Scholar
  6. 6.
    M. Hansen, “Constitution of Binary Alloys” (McGraw-Hill, N.Y., 1958) p. 771.Google Scholar
  7. 7.
    K. L. Chopra, P. Nath and A. C. Rastogi, Phys. Stat. Sol. (a) 27 (1975) 645.Google Scholar
  8. 8.
    H. A. Davies and J. B. Hull, J. Mater. Sci. 9 (1974) 707.Google Scholar
  9. 9.
    N. I. Varich and A. A. Yakunin, Russian J. Phys. Chem. 41 (1967) 437.Google Scholar
  10. 10.
    E. Kneller, J. Appl. Phys. 33 (1962) 1355.Google Scholar
  11. 11.
    Idem, ibid. 35 (1964) 2210.Google Scholar
  12. 12.
    T. B. Light, Phys. Rev. Letters 22 (1969) 999.Google Scholar
  13. 13.
    H. S. Randhawa, L. K. Malhotra, H. K. Sehgal and K. L. Chopra, Phys. Stat. Sol. (a) 37 (1976) 313.Google Scholar
  14. 14.
    P. Boolchand, M. Blizzard, H. S. Randhawa, D. K. Pandya, P. Nath and K. L. Chopra, Proceedings of the Seventh International Conference on Amorphous and Liquid Semiconductors, Edinburgh (June 1977).Google Scholar
  15. 15.
    U. Koster, Acta Metall. 20 (1972) 1361.Google Scholar
  16. 16.
    H. S. Randhawa, L. K. Malhotra and K. L. Chopra, J. Non-Crystal. Solids 29 (1978) 311.Google Scholar

Copyright information

© Chapman and Hall Ltd. 1980

Authors and Affiliations

  • Dilshad Akhtar
    • 1
  • T. C. Goel
    • 1
  • V. D. Vankar
    • 1
  • K. L. Chopra
    • 1
  1. 1.Indian Institute of TechnologyNew DelhiIndia

Personalised recommendations