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Dewetting of thin films on heterogeneous substrates: Pinning vs. coarsening

Lutz Brusch·Heiko Kuehne·Uwe Thiele·Markus Baer
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Abstract

We study a model for a thin liquid film dewetting from a periodic heterogeneous substrate (template). The amplitude and periodicity of a striped template heterogeneity necessary to obtain a stable periodic stripe pattern, i.e. pinning, are computed. This requires a stabilization of the longitudinal and transversal modes driving the typical coarsening dynamics during dewetting of a thin film on a homogeneous substrate. If the heterogeneity has a larger spatial period than the critical dewetting mode, weak heterogeneities are sufficient for pinning. A large region of coexistence between coarsening dynamics and pinning is found.

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Lutz Brusch, Heiko Kuehne, Uwe Thiele, Markus Baer. 2001-12-10. Dewetting of thin films on heterogeneous substrates: Pinning vs. coarsening. https://doi.org/10.1103/physreve.66.011602

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