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arXiv · 1406.0780

PANIC: a 3D dislocation dynamics model for climb and glide in epitaxial films and heterostructures

Wai Yuen Fu·Colin J. Humphreys·Michelle A. Moram
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Abstract

This paper presents PANIC, a 3D discrete mesoscale dislocation dynamics model which includes a fully quantitative treatment of both dislocation climb and dislocation glide, including climb driven by both osmotic and mechanical stresses and climb enabled by both bulk and pipe diffusion, including full elastic anisotropy for materials with hexagonal symmetry. Efficient calculations can be performed for epitaxial thin films, multilayers and device structures with free surfaces, including those with irregular geometries (e.g. islands). The model also includes the capability to simulate dislocation dynamics during the growth of the thin films or heterostructures. The model has been validated against experiment for thin films of GaN, AlN and AlGaN but is widely applicable to other material systems, both hexagonal and cubic.

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Wai Yuen Fu, Colin J. Humphreys, Michelle A. Moram. 2014-06-03. PANIC: a 3D dislocation dynamics model for climb and glide in epitaxial films and heterostructures. https://arxiv.org/abs/1406.0780

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