Date of Original Version
Copyright 2010 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article may be found at http://dx.doi.org/10.1063/1.3517158
Abstract or Description
We predict the cross-plane phononthermal conductivity of Stillinger-Weber siliconthin films as thin as 17.4 nm using the lattice Boltzmann method. The thin films are modeled using bulk phononproperties obtained from harmonic and anharmonic lattice dynamics calculations. We use this approach, which considers all of the phonons in the first Brillouin-zone, to assess the suitability of common assumptions. Specifically, we assess the validity of: (i) neglecting the contributions of optical modes, (ii) the isotropic approximation, (iii) assuming an averaged bulk mean-free path, and (iv) the Matthiessen rule. Because the frequency-dependent contributions to thermal conductivity change as the film thickness is reduced, assumptions that are valid for bulk are not necessarily valid for thin films.
Journal of Applied Physics, 108, 113524.