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arXiv · 1210.7899

Competing Atomic and Molecular Mechanisms of Thermal Oxidation

Xiao Shen·Sokrates T. Pantelides
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Abstract

The oxidation of SiC and Si provide a unique opportunity for studying oxidation mechanisms because the product is the same, SiO2. Silicon oxidation follows a linear-parabolic law, with molecular oxygen identified as the oxidant. SiC oxidation obeys the same linear-parabolic law but has different rates and activation energies and exhibits much stronger face-dependence. Using results from first-principles calculations, we show that atomic and molecular oxygen are the oxidant for Si- and C-face SiC respectively. Comparing SiC with Si, we elucidate how the interface controls the competition between atomic and molecular mechanisms.

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Xiao Shen, Sokrates T. Pantelides. 2012-10-30. Competing Atomic and Molecular Mechanisms of Thermal Oxidation. https://doi.org/10.1063/1.4815962

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