Skip to main content Accessibility help

The Influence of Strain-Mediated Morphological Changes on the Structural and Optical Properties of MBE-Grown GeSi/Si

  • D. D. Perovic (a1), J. Whitehurst (a1), J. P. Noel (a2), N. L. Rowell (a2) and D. C. Houghton (a2)...


Recent studies on strained layer heteroepitaxy in high misfit systems (eg. Ge on Si) have clearly indicated the importance of elastic strain on a number of surface-mediated growth effects. In this work we consider the transition from ideal, 2-D layer-by-layer growth to the initial stages of a 3-D growth morphology as a precursor to misfit dislocation injection in GexSi1−x/Si heterostructures with x as low as 0.15. Experimentally, we have studied a wide range of MBE-and CVD-grown single and multilayer GexSi1−x/Si (x<0.5) structures using transmission electron microscopy and photoluminescence spectroscopy. Firstly, we describe a new mechanism for the heterogeneous nucleation of misfit dislocations in strained epitaxial layers, the ‘double half-loop’ source, which originates from atomic-scale (<1.5 nm) interfacial perturbations. Secondly, the atomic-scale dilatational perturbations, which can exist in areal densities up to ∼109 cm−2, have been identified as the origin of intense, broad-band PL from MBE-grown GexSi1−x/Si strained layers. The change in PL behaviour with increasing strained layer thickness has been used to study the effects of elastic strain-induced surface roughening at low misfits.



Hide All
1. For a recent review see: Eberl, K. and Wegscheider, W., to be published in: Handbook of Semiconductors, Vol. 3: Materials, Properties and Preparation, edited by, Mahajan, S..
2. Perovic, D.D., Weatherly, G.C., Baribeau, J.-M. and Houghton, D.C., Thin Solid Films, 183, 141 (1989).
3. Houghton, D.C., J. Appl. Phys., 70, 2136 (1991).
4. The use of plan-view imaging from wedge-profile specimen regions, where the heterostructure interfaces are clearly delineated due to thin foil surface relaxation effects [see Perovic, D.D. and Weatherly, G.C., Ultramicroscopy, 35, 271 (1991)], allows for representative imaging of defect configurations within specific areas of a given heterostructure without the need for cross-sectional analysis.
5. Noël, J.-P., Rowell, N.L., Houghton, D.C., Wang, A. and Perovic, D.D., Appl. Phys. Lett., 61, 690 (1992).
6. Sturm, J.C., Manoharn, H., Lenchyshyn, L.C., Thewalt, M.W., Rowell, N.L., Noël, J.-P. and Houghton, D.C., Phys. Rev. Lett., 66, 1362 (1991).
7. Bean, J.C., Feldman, L.C., Fiory, A.T., Nakahara, S. and Robinson, I.K., J. Vac. Sci. Technol. A, 2, 436 (1984).
8. Hoeven, A.J., Lenssinck, J.M., Dijkkamp, D., van Loenen, E.J. and Dieleman, J., Phys. Rev. Lett., 63, 1830 (1989).
9. Swartzentruber, B.S., Mo, Y.-W., Webb, M.B. and Lagally, M.G., J. Vac. Sci. Technol. A, 7, 2901 (1989).
10. Such an argument has previously been used to explain step-driven, long-range ordering in GexSi1−xt/Si; see: Jesson, D.E., Pennycook, S.J., Baribeau, J.-M. and Houghton, D.C., Phys. Rev. Lett., 68, 2062 (1992).
11. Perovic, D.D. and Houghton, D.C., in: Mechanisms of Heteroepitaxial Growth, edited by, Chisholm, M.F., Garrison, B.J., Hull, R. and Schowalter, L.J., Mat. Res. Soc. Symp. Proa, Vol. 263 (1992).


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