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arXiv · 1010.0193

Internal Stresses and Formation of Switchable Nanowires at Thin Silica Film Edge

J. C. Phillips
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Abstract

At vertical edges, thin films of silicon oxide (SiO_{2-x}) contain semiconductive c-Si layered nanocrystals (Si NC) embedded in and supported by an insulating g-SiO2 matrix. Tour et al. have shown that a trenched thin film geometry enables the NC to form switchable nanowires (SNW) when trained by an applied field. The field required to form SNW decreases rapidly within a few cycles, or by annealing at 600 C in even fewer cycles, and is stable to 700C. Here we describe the intrinsic evolution of Si NC and SNW in terms of the competition between internal stresses and electro-osmosis. The analysis relies heavily on experimental data from a wide range of thin film studies, and it explains why a vertical edge across the planar Si-SiOx interface is necessary to form SNW. The discussion also shows that the formation mechanisms of Si NC and Si/SiO_{2-x} SNW are intrinsic and result from optimization of nanowire conductivity in the presence of residual host misfit stresses.

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J. C. Phillips. 2010-10-01. Internal Stresses and Formation of Switchable Nanowires at Thin Silica Film Edge. https://doi.org/10.1063/1.3532035

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