Autor: |
Schifani, Guido, Frisch, Thomas, Argentina, Mederic, Aqua, Jean-Noël |
Rok vydání: |
2016 |
Předmět: |
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Zdroj: |
Phys. Rev. E 94, 042808 (2016) |
Druh dokumentu: |
Working Paper |
DOI: |
10.1103/PhysRevE.94.042808 |
Popis: |
We investigate the formation and the coarsening dynamics of islands in a strained epitaxial semi-conductor film. These islands are commonly observed in thin films undergoing a morphological instability due to the presence of the elasto capillary effect. We first describe both analytically and numerically the formation of an equilibrium island using a two dimensional continuous model. We have found that these equilibrium island-like solutions have a maximum height $h_0$ and they sit on top of a flat wetting layer with a thickness $h_w$. We then consider two islands and we report that they undergo a non-interrupted coarsening that follows a two stage dynamics. The first stage may be depicted by a quasi-static dynamics, where the mass transfers are proportional to the chemical potential difference of the islands. It is associated with a time scale $t_c$ that is function of the distance $d$ between the islands, and leads to the shrinkage of the smallest island. Once its height becomes smaller than a minimal equilibrium height $h_{0}^{*}$, its mass spreads over the entire system. Our results pave the way for a future analysis of coarsening of an assembly of islands. |
Databáze: |
arXiv |
Externí odkaz: |
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