Effects of strain on island morphology and size distribution in irreversible submonolayer growth

Abstract

The effects of strain on the island morphology and size distribution in irreversible submonolayer growth with rapid island relaxation are investigated. In our simulations the strain energy is approximated by an isotropic $1∕{r}^{3}$ interaction. While the island density increases with strain, in the presence of sufficient island relaxation due to edge diffusion, the island shape changes from square to rectangular. However, due to fluctuations, there is a broad distribution of island widths. General scaling forms for the island width and island-length distributions are derived and good scaling is obtained as a function of coverage while there is only a relatively weak dependence on the strain. The scaled island-size distribution is also found to be only weakly affected by strain. These latter results are in qualitative agreement with recent experimental results for $\mathrm{In}\mathrm{As}∕\mathrm{Ga}\mathrm{As}(100)$ growth.