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arXiv · 1204.5556

Intrinsic Origin of Negative Fixed Charge in Wet Oxidation for Silicon Carbide

Yasuhiro Ebihara·Kenta Chokawa·Shigenori Kato·Katsumasa Kamiya·Kenji Shiraishi
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Abstract

We demonstrate on the basis of first-principles calculations that the formation of carbonate-like moiety in SiO$_2$ could be the intrinsic origin of negative fixed charge in SiC thermal oxidation. We find that two possible origins for the negative fixed charges are O-lone-pair state and a negatively charged CO$_3$ ion in SiO$_2$. Such CO$_3$ ion is able to be formed as a result of the existence of residual C atoms in SiO$_2$, which are expected to be emitted from the interface between SiC and SiO$_2$, and the incorporation of H atoms during wet oxidation.

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Yasuhiro Ebihara, Kenta Chokawa, Shigenori Kato, Katsumasa Kamiya, Kenji Shiraishi. 2012-04-25. Intrinsic Origin of Negative Fixed Charge in Wet Oxidation for Silicon Carbide. https://doi.org/10.1063/1.4722782

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