Phonons and Optical Properties of Si/Ge Superlattices

  • G. Abstreiter
  • K. Eberl
  • E. Friess
  • U. Menczigar
  • W. Wegscheider
  • R. Zachai
Part of the NATO ASI Series book series (NSSB, volume 206)

Abstract

Short period Si/Ge superlattices are new semiconductor materials whose band structure and consequently whose electrical and optical properties can be changed in a wide range. New device applications are expected on the basis of such layered structures | 1 |. Recent progress on low temperature molecular beam epitaxial growth | 2,3,4,5 | allows the realization of high quality Si/Ge superlattices with sharp interfaces and individual layer thicknesses of only a few monolayers. The large lattice mismatch of more than 4 % between the two constituents, however, still causes major problems for the achievement of sufficient total thickness, which is required for the application of new superlattice effects. The concept of strain symmetrization with certain buffer layers | 4,6 | might be one way to overcome this problem. Various basic properties of such new superlattice materials can be studied, however, also in relatively thin Si/Ge superlattices grown on Si, Ge, and SiGe substrates. In the present article results, obtained mainly in our group are reviewed. The excellent work of various other research groups from all over the world can be found in the literature | 7 |.

Keywords

Period Length Super Lattice Longitudinal Acoustical Strain Layer Superlattices Layer Superlattices 
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.

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References

  1. 1.
    see for example: E. Kasper, SiGe/Si superlattices strain influence and devices, in: “Heterostructures on Silicon: One step further with Silicon,” Y. I. Nissim, and E. Rosencher, eds., Nato ASI Series Vol. 160, Dordrecht, (1989).Google Scholar
  2. 2.
    J. C. Bean, L. C. Feldmann, A. T. Fiory, S. Nakahara, and J. K. Robinson, GexSil_x/Si strained-layer superlattices grown by molecular beam epitaxy, J. Vacuum Sci. Technol. A2: 436 (1984).ADSCrossRefGoogle Scholar
  3. 3.
    K. Eberl, W. Wegscheider, E. Friess, and G. Abstreiter, Realization of short period Si/Ge strained layer superlattices, in: ref. 1.Google Scholar
  4. 4.
    E. Kasper, H. Kibbel, H. Jorke, H. Brugger, E. Friess, and G. Abstreiter, Symmetrically strained Si/Ge superlattices on Si substrates, Phys. Rev. B 38: 3599 (1988).CrossRefGoogle Scholar
  5. 5.
    G. Abstreiter, K. Eberl, E. Friess, W. Wegscheider, and R. Zachai, Silicon/Germanium strained layer superlattices, Journal of Crystal Growth 95: 431 (1989).ADSCrossRefGoogle Scholar
  6. 6.
    K. Eberl, E. Friess, W. Wegscheider, U. Menczigar, and G. Abstreiter, Improvement of structural properties of Si/Ge superlattices, E-MRS Meeting, Strasbourg (1989), to be published in: Thin Solid Films.Google Scholar
  7. 7.
    see for example publications in conference proceedings of Refs. 1 and 6.Google Scholar
  8. 8.
    E. Kasper, H. J. Herzog, H. Jorke, and G. Abstreiter, Strain adjustment in Si/Ge superlattices, Mat. Res. Soc. Symp. Proc. Vol. 102: 393 (1988).CrossRefGoogle Scholar
  9. 9.
    M. A. Renucci, J. B. Renucci, and M, Cardona, Raman scattering in Ge-Si alloys, in: “Light scattering in Solids,” M. Balkanski, ed., Flammarion, Paris (1971).Google Scholar
  10. 10.
    C. Colvard, T. A. Gant, M. V. Klein, R. Merlin, R. Fischer, H. Morkoc, and A. C. Gossard, Folded acoustic and quantized optic phonons in (GaAl)As superlattices, Phys. Rev. B31: 2080 (1985).CrossRefGoogle Scholar
  11. 11.
    H. Brugger, G. Abstreiter, H. Jorke, H. J. Herzog, and E. Kasper, Folded acoustic phonons in Si-SixGel_x super-lattices, Phys. Rev. B33: 5928 (1986).CrossRefGoogle Scholar
  12. 12.
    E. Molinari, A. Fasolino, Calculated phonon spectra of Si/Ge (001) superlattices: Features for interface characterization, Appl. Phys. Lett. 54: 1220 (1989).Google Scholar
  13. 13.
    M. I. Alonso, F. Cerdeira, D. Miles, M. Cardona, E. Kasper, and H. Kibbel, Raman spectra of SinGem superlattices: theory and experiment, preprint.Google Scholar
  14. 14.
    J. White, G. Fasol, R. Ghanbari, C. J. Gibbings, and C. G. Tuppen, Calculation of energies and Raman intensities of confined phonons in Si-Ge strained layer superlattices, in: Ref. 6.Google Scholar
  15. 15.
    M. Ospelt, K. A. Mäder, W. Bacsa, J. Henz, and H. von Känel, Unstrained vs. strained layer epitaxy: Thick Ge-layers and Ge/Si superlattices on Si(100), in: Ref. 1.Google Scholar
  16. 16.
    E. Friess, H. Brugger, K. Eberl, G. Krötz, and G. Abstreiter, Confined optical modes in short period (110) Si/Ge super-lattices, Solid State Communications 69: 899 (1989).ADSCrossRefGoogle Scholar
  17. 17.
    R. Zachai, E. Friess, G. Abstreiter, E. Kasper, and H. Kibbel, Band structure and optical properties of strain symmetrized short period Si/Ge superlattices on Si (100) substrates, in: “19th International Conference on the Physics of Semiconductors,” W. Zawadzki, ed., Insitute of Physics, Polish Academy of Sciences, Warsaw (1988).Google Scholar
  18. 18.
    see for example A. K. Sood, J. Menéndez, M. Cardona, and K. Ploog, Resonance Raman scattering by confined LO and TO phonons in GaAs-AlAs superlattices, Phys, Rev. Lett. 54: 2111 (1985).Google Scholar
  19. 19.
    H. Brugger, E. Friess, G. Abstreiter, E. Kasper, and H. Kibbel, Annealing effects in short period Si-Ge strained layer superlattices, Semicond. Sci. Technol. 3: 1166 (1988)ADSGoogle Scholar
  20. 20.
    T. P. Pearsall, J. Bevk, L. C. Feldmann, J. M. Boyar, J. P. Mannaerts, and A. Ourmazd, Structurally induced optical transitions in Si-Ge superlattices, Phys. Rev. Lett. 58:729 (1987), T. P. Pearsall, Germanium-Silicon alloys and Heterostructures - Optical and electronic properties, CRC Critical Rev. of Solid State and Materials Sciences, in press.Google Scholar
  21. 21.
    D. V. Lang, R. People, J. C. Bean, and A. M. Sergent, Measurements of the band gap of GexSii_x/Si strained layer heterostructures, Appl. Phys. Lett. 47: 1333 (1985).Google Scholar
  22. 22.
    R. Zachai, K. Eberl, and G. Abstreiter, Photoluminescence in Si/Ge superlattices with different strain distributions, to be published.Google Scholar
  23. 23.
    S. Froyen, D. M. Wood, and A. Zunger, Structural and electronic properties of epitaxial thin-layer SinGen super-lattices, Phys. Rev.B 37: 6893 (1988).CrossRefGoogle Scholar
  24. 24.
    S. Satpathy, R. M. Martin, and C. G. van de Walle, Theory of electronic properties of the (100) Si/Ge strained-layer superlattices, Phys. Rev. B 38: 13237 (1988).CrossRefGoogle Scholar
  25. 25.
    M. S. Hybertsen and M. Schlüter, Theory of optical transitions in Si/Ge (001) strained-layer superlattices, Phys.. Rev. B 36: 9683 (1987).CrossRefGoogle Scholar
  26. 26.
    I. Morrison and M. Jaros, Electronic and optical properties of ultrathin Si/Ge (001) superlattices, Phys. Rev. B 37: 916 (1988).CrossRefGoogle Scholar
  27. 27.
    M. A. Gell, Effect of buffer-layer composition on new optical transitions in Si/Ge short-period superlattices, Phys. Rev. B 38: 7535 (1988).CrossRefGoogle Scholar
  28. 28.
    U. Gnutzmann and K. Clausecker, Theory of direct optical transition in an optical indirect semiconductor with a superlattice structure, Appl. Phys. B 36: 1310 (1987).Google Scholar
  29. 29.
    R. People and S. A. Jackson, Indirect, quasi-direct, and direct optical transitions in the pseudomorphic (4 x 4)monolayer Si-Ge strained -layer superlattices on Si (001), Phys. Rev. B 36: 1310 (1987).CrossRefGoogle Scholar
  30. 30.
    F. Cerdeira, M. I. Alonso, D. Niles, M. Garriga, M. Cardona, E. Kasper,and H. Kibbel, Resonant Raman scattering in short-period SinGem superlattices, preprint.Google Scholar
  31. 31.
    U. Menczigar, E. Friess, K. Eberl, and G. Abstreiter, Resonant Raman scattering in ultrathin Si/Ge strained-layer superlattices, to be published.Google Scholar

Copyright information

© Springer Science+Business Media New York 1989

Authors and Affiliations

  • G. Abstreiter
    • 1
  • K. Eberl
    • 1
  • E. Friess
    • 1
  • U. Menczigar
    • 1
  • W. Wegscheider
    • 1
  • R. Zachai
    • 1
  1. 1.Walter Schottky InstitutTechnical University MunichGarchingFed. Rep. of Germany

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