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Epitaxial Growth in Dislocation-Free Strained Alloy Films

Published online by Cambridge University Press:  01 February 2011

Zhi-Feng Huang  and
Rashmi C. Desai
Zhi-Feng Huang
Affiliation:
email: [email protected] Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A7.
Rashmi C. Desai
Affiliation:
email: [email protected] Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A7.
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Abstract

The morphological and compositional instabilities in the heteroepitaxial strained alloy films have attracted intense interest from both experimentalists and theorists. To understand the mechanisms and properties for the generation of instabilities, we have developed a nonequilibrium, continuum model for the dislocation-free and coherent film systems. The early evolution processes of surface pro.les for both growing and postdeposition (non-growing) thin alloy films are studied through a linear stability analysis. We consider the coupling between top surface of the film and the underlying bulk, as well as the combination and interplay of different elastic effects. These e.ects are caused by filmsubstrate lattice misfit, composition dependence of film lattice constant (compositional stress), and composition dependence of both Young's and shear elastic moduli. The interplay of these factors as well as the growth temperature and deposition rate leads to rich and complicated stability results. For both the growing.lm and non-growing alloy free surface, we determine the stability conditions and diagrams for the system. These show the joint stability or instability for film morphology and compositional pro.les, as well as the asymmetry between tensile and compressive layers. The kinetic critical thickness for the onset of instability during.lm growth is also calculated, and its scaling behavior with respect to misfit strain and deposition rate determined. Our results have implications for real alloy growth systems such as SiGe and InGaAs, which agree with qualitative trends seen in recent experimental observations.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 715: Symposium A – Amorphous and Heterogeneous Silicon-Based Films-2002 , 2002 , A19.10
Copyright
Copyright © Materials Research Society 2002

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References

[1] Asaro, R. J. and Tiller, W. A., Metall. Trans. 3, 1789 (1972). M. A. Grinfeld, Sov. Phys. Dokl. 31, 831 (1987); D. J. Srolovitz, Acta Metall. 37, 621 (1989).Google Scholar
[2] Cahn, J. W., Acta. Metall. 9, 795 (1961). Trans. Metall. Soc. AIME 242, 166 (1968).Google Scholar
[3] Huang, Z.F. and Desai, R.C., Instability and decomposition on the surface of strained alloy films, Phys. Rev. B (accepted); and Z.F. Huang and R.C. Desai, Epitaxial growth in dislocation-free strained alloy films: Morphological and compositional instabilities, Phys. Rev. B (submitted).Google Scholar
[4] L'eonard, F. and Desai, R. C., Thin Solid Films 357, 46 (1999).Google Scholar
[5] L'eonard, F. and Desai, R. C., Phys. Rev. B 57, 4805 (1998).Google Scholar
[6] Spencer, B. J., Voorhees, P. W., and Terso, J.., Phys. Rev. B, 64, 235318 (2001).Google Scholar
[7] Guyer, J. E. and Voorhees, P. W., Phys. Rev. B 54, 11710 (1996).Google Scholar
[8] L'eonard, F. and Desai, R. C., Phys. Rev. B 56, 4955 (1997).Google Scholar