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arXiv · 0705.2354

Nonlinear evolution of a morphological instability in a strained epitaxial film

Jean-Noel Aqua·Thomas Frisch·Alberto Verga
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Abstract

A strained epitaxial film deposited on a deformable substrate undergoes a morphological instability relaxing the elastic energy by surface diffusion. The nonlinear and nonlocal dynamical equations of such films with wetting interactions are derived and solved numerically in two and three dimensions. Above some critical thickness, the surface evolves towards an array of islands separated by a wetting layer. The island chemical potential decreases with its volume, so that the system experiences a non-interrupted coarsening described by power laws with a marked dimension dependence.

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Jean-Noel Aqua, Thomas Frisch, Alberto Verga. 2007-05-16. Nonlinear evolution of a morphological instability in a strained epitaxial film. https://doi.org/10.1103/physrevb.76.165319

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