Heteroepitaxial modeling on strained surfaces using a mean field appraoch

J. DeGraffenreid and J.A. Venables
Mater. Res. Soc. Symp. Proc. 1130 (2009) W06-38


We model heteroepitaxial growth using a recently developed extension of mean field nucleation and growth theory to cases involving strain [1]. The influence of strain is included as a change in the diffusion energy, and as a change in potential energy at the lattice sites; both of these energies are linear, but independent, functions of strain. In a one-dimensional model, we consider a monolayer high island using the flat island approximation for the strain, and explore the parameter space of repulsive and attractive interactions between the island and the diffusing ad-particles. We follow Zinovyev et al. [2] and Huang et al. [3] in using parameters appropriate to Ge/Ge(001), and Ge on the wetting layer of Ge/Si(001). While both the change in diffusion energy and in the repulsive potential are important in determining the size of a germanium island after deposition, our calculations show for this particular case that the dominant change is the increase of the diffusion constant of Ge ad-particles on the compressed wetting layer of Ge/Si(001) relative to bulk Ge(001).

1. R. Grima, J. DeGraffenreid and J.A. Venables, Phys. Rev. B 76, 233405 (2007)

2. V. Zinovyev, G. Vastola, F. Montalenti and L. Miglio, Surface Sci. 600, 4777 (2006)

3. L. Huang, F. Liu and X.G. Gong, Phys. Rev. B 70, 155320 (2004)

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Latest version of this document: 22nd February 2010.