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arXiv · 1901.07730

Structure and energetics of carbon-related defects in SiC (0001)/SiO$_{\rm 2}$ systems revealed by first-principles calculations: Defects in SiC, SiO$_{\rm 2}$, and just at their interface

Takuma Kobayashi·Yu-ichiro Matsushita
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Abstract

We report first-principles calculations that reveal the atomic forms, stability, and energy levels of carbon-related defects in SiC (0001)/SiO$_{\rm 2}$ systems. We clarify the stable position (SiC side, SiO$_{\rm 2}$ side, or just at the SiC/SiO$_{\rm 2}$ interface) of defects depending on the oxidation environment. Under an O-rich condition, the di-carbon antisite ((C$_{\rm 2}$)$_{\rm Si}$) in the SiC side is stable and critical for $n$-channel MOSFETs, whereas the di-carbon defect (Si-C-C-Si) at the interface becomes critical under an O-poor condition. Our results suggest that the oxidation of SiC under a high-temperature O-poor condition is favorable in reducing the defects, in consistent with recent experimental reports.

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Takuma Kobayashi, Yu-ichiro Matsushita. 2019-01-23. Structure and energetics of carbon-related defects in SiC (0001)/SiO$_{\rm 2}$ systems revealed by first-principles calculations: Defects in SiC, SiO$_{\rm 2}$, and just at their interface. https://doi.org/10.1063/1.5100754

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