Formation of nanopillar arrays in ultrathin viscous films: the critical role of thermocapillary stresses.

  title={Formation of nanopillar arrays in ultrathin viscous films: the critical role of thermocapillary stresses.},
  author={Mathias Dietzel and Sandra M. Troian},
  journal={Physical review letters},
  volume={103 7},
Experiments by several groups during the past decade have shown that a molten polymer nanofilm subject to a large transverse thermal gradient undergoes spontaneous formation of periodic nanopillar arrays. The prevailing explanation is that coherent reflections of acoustic phonons within the film cause a periodic modulation of the radiation pressure which enhances pillar growth. By exploring a deformational instability of particular relevance to nanofilms, we demonstrate that thermocapillary… 

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