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Atomic-Scale Dynamics of the Formation and Dissolution of Carbon Clusters in SiO2

Sanwu Wang·Massimiliano Di Ventra·S. G. Kim·Sokrates T. Pantelides
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Abstract

Oxidation of SiC produces SiO2 while CO is released. A `reoxidation' step at lower temperatures is, however, necessary to produce high-quality SiO2. This step is believed to cleanse the oxide of residual C without further oxidation of the SiC substrate. We report first-principles calculations that describe the nucleation and growth of O-deficient C clusters in SiO2 under oxidation conditions, fed by the production of CO at the advancing interface, and their gradual dissolution by the supply of O under reoxidation conditions. We predict that both CO and CO2 are released during both steps.

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Sanwu Wang, Massimiliano Di Ventra, S. G. Kim, Sokrates T. Pantelides. 2001-05-29. Atomic-Scale Dynamics of the Formation and Dissolution of Carbon Clusters in SiO2. https://doi.org/10.1103/physrevlett.86.5946

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