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arXiv · 1608.01885

Density functional theory calculations of the stress of oxidised (110) silicon surfaces

C Melis·S Giordano·L Colombo·G Mana
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Abstract

The measurement of the lattice-parameter of silicon by x-ray interferometry assumes the use of strain-free crystals. This might not be the case because surface relaxation, reconstruction, and oxidation cause strains without the application of any external force. In a previous work, this intrinsic strain was estimated by a finite element analysis, where the surface stress was modeled by an elastic membrane having a 1 N/m tensile strength. The present paper quantities the surface stress by a density functional theory calculation. We found a value exceeding the nominal value used, which potentially affects the measurement accuracy.

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C Melis, S Giordano, L Colombo, G Mana. 2016-08-05. Density functional theory calculations of the stress of oxidised (110) silicon surfaces. https://doi.org/10.1088/0026-1394/53/6/1339

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