Skip to main content Accessibility help

Photoluminescence from Coherently Strained Si1−xGex Alloys

  • N.L. Rowell (a1), J.-P. Noël (a1), D.C. Houghton (a1) and D.D. Perovic (a1)


An intense, broad photoluminescence PL peak, with an internal quantum efficiency as high as 31%, has been observed from a variety of structures containing Si1−xGex strained layers on Si(100) substrates; i.e. Si1−xGex thick random alloy layers, single quantum wells (SQW) and multiple quantum wells (MQW) with layers thick enough so that zone folding effects were not relevant. This peak, which shifted consistently and predictably with Ge concentration( 0.06 < × < 0.53), had its high energy edge near the established band gap for strained SiGe. PL excitation spectroscopy indicated that no phonons were involved in the process causing the SiGe PL peak. Samples deposited at ~ 400 °C exhibited low PL intensity, whereas annealing at ~ 600 °C enhanced the intensity by as much as two orders of magnitude. This anneal treatment was found to remove grown-in defect complexes without creating a significant density of misfit dislocations. The PL peak energy at 4.2 K varied from 620 to 990 meV for Ge fractions x from 0.53 to 0.06. When the samples were forced to relax, e.g. by higher temperature annealing, the luminescence of this peak either shifted to near the relaxed bandgap or was quenched by deep, dislocation related states. Prior to such relaxation, the efficient PL was due to exciton accumulation in the strained Si1−xGex layers of single and multiple quantum wells, where the bandgap was locally reduced. It is suggested that the recombination of electrons and holes occuring within a high-density electron hole condensate (EHC) can cause the observed spectrum.



Hide All
1. Zachai, R., Eberl, K., Abstreiter, G., Kasper, E. and Kibbel, H., Phys. Rev. Lett. 64, 1055 (1990).10.1103/PhysRevLett.64.1055
2. Montie, E.A., Walle, G.F.A. Van de, Gravesteijn, D.J., Gorkum, A.A. Van and Bulle-Lieuwma, C.W.T., Appl. Phys. Lett. 56, 340(1990).10.1063/1.102802
3. Abstreiter, G., Thin Solid Films 183, 1 (1989).10.1016/0040-6090(89)90423-9
4. Gell, M.A., Phys. Rev. B3, 7535 (1988).10.1103/PhysRevB.38.7535
5. Nodl, J.-P., Greene, J.E., Rowell, N.L., Kechang, S. and Houghton, D.C., Appl. Phys. Lett. 55, 1525 (1989).
6. Noël, J.-P., Greene, J.E., Rowell, N.L. and Houghton, D.C., Appl.Phys. Lett. 56, 265 (1990).10.1063/1.102804
7. Schowalter, L.J., Steranka, F.M., Salamon, M.B., and Wolfe, J.P., Phys. Rev. B29, 2970 (1984).10.1103/PhysRevB.29.2970
8. Weman, H. and Monemar, B., Mat. Res. Soc. Annual Mtg., Boston, December 1989.
9. Houghton, D.C., Lockwood, D.J., Dharma-Wardana, M.W.C., Fenton, E.W., Baribeau, J.-M. and Denhoff, M.W., J. Crystal Growth 81, 434(1987).10.1016/0022-0248(87)90429-5
10. Houghton, D.C., Appl. Phys. Lett., in press.
11. Rowell, N.L. and Young, R.B., Proc. SPIE 1145, 80 (1989).
12. Buijs, H., private communication.
13. Thewalt, M.L., private communication.
14. Klein, M.V., Sturge, M.D., and Cohen, E., Phys. Rev. B25, 4331 (1982).10.1103/PhysRevB.25.4331
15. Simon, A.H., Steranka, F.M., and Wolfe, J.P., Phys. Rev. B40, 4003 (1989).10.1103/PhysRevB.40.4003
16. Lang, D.V., People, R., Bean, J.C., and Sergent, A.M., Appl. Phys. Lett. 47, 1333 (1985).10.1063/1.96271
17. Davies, G., Physics Reports 176, 83 (1989).10.1016/0370-1573(89)90064-1
18. Weber, J. and Alonso, M.I., Phys. Rev. B40, 5683 (1989).10.1103/PhysRevB.40.5683
19. Hammond, R.B., McGill, T.C., and Mayer, J.M., Phys. Rev. B13, 3566 (1976).10.1103/PhysRevB.13.3566

Photoluminescence from Coherently Strained Si1−xGex Alloys

  • N.L. Rowell (a1), J.-P. Noël (a1), D.C. Houghton (a1) and D.D. Perovic (a1)


Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed