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arXiv · 2609.28891

Influence of chemical vapor deposition conditions on N incorporation ratio on vicinal 4H-SiC(000-1) surface: Ab Initio-based approach

Wataru Ota·Akira Kusaba·Yoshihiro Kangawa·Keisuke Kurashima·Ichiro Mizushima·Kenji Shiraishi
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Abstract

In experimental studies, increasing the ratio of source gases (C3H8/SiH4; C/Si ratio) for chemical vapor deposition (CVD) causes the growth rate to increase monotonically, and nitrogen incorporation tends to decrease accordingly; however, a unique phenomenon has been observed in which nitrogen incorporation increases discontinuously in the range of C/Si ratio between 1.0 and 1.5. This phenomenon is specific to the vicinal 4H-SiC(000-1) C-face and is not observed on the vicinal 4H-SiC(0001) Si-face. In this study, N incorporation behavior on a vicinal C-face during CVD is investigated using an ab initio-based approach. The calculation results suggest that when C/Si ratio is less than 1.0, the Si-terminated step edge is stable, whereas when C/Si ratio exceeds 1.0, the existence probability of the C-H-terminated step edge, where the N substitution energy is lower than in the former case, increases sharply. This change in the step-edge state across C/Si = 1.0 is thought to be the cause of the discontinuous increase in N incorporation.

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Wataru Ota, Akira Kusaba, Yoshihiro Kangawa, Keisuke Kurashima, Ichiro Mizushima, Kenji Shiraishi. 2026-09-24. Influence of chemical vapor deposition conditions on N incorporation ratio on vicinal 4H-SiC(000-1) surface: Ab Initio-based approach. https://arxiv.org/abs/2609.28891

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