Mechanisms of mound coarsening in unstable epitaxial growth
نویسنده
چکیده
Corner diffusion is shown to play a crucial role in determining the asymptotic mound coarsening exponent n in the case of unstable epitaxial growth on (001) and (111) surfaces. For the case of island-relaxation without corner diffusion the asymptotic exponent is found to satisfy n.1/4. However, when rapid cornerdiffusion is allowed, the coarsening exponent is found to approach 1/3. An explanation for these results is presented in terms of the effects of corner diffusion on the surface current and mound morphology. @S0163-1829~99!51440-9#
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تاریخ انتشار 1999