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arXiv · 2506.23912

Density functional theory study of effect of NO annealing on electronic structure and carrier-scattering property of 4H-SiC(0001)/SiO$_2$ interface

Nahoto Funaki·Kosei Sugiyama·Mitsuharu Uemoto·Tomoya Ono
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Abstract

The effect of the nitrided layer introduced by NO annealing on the electronic structure and carrier scattering property of the 4H-SiC(0001)/SiO$_2$ interface is investigated by the density functional theory calculation using the interface models where the areal N atom density corresponds to that in practical devices. The areal N atom density is one third of the areal C atom density in practical devices. It is found that the nitrided layer screens the unfavorable Coulomb interaction of O atoms in the SiO$_2$. However, the electrons flowing under the nitrided layer are significantly scattered by the fluctuation of potential due to the low areal N atom density. These results imply that the areal N atom density should be increased so that the fluctuation of potential is suppressed.

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Nahoto Funaki, Kosei Sugiyama, Mitsuharu Uemoto, Tomoya Ono. 2025-06-30. Density functional theory study of effect of NO annealing on electronic structure and carrier-scattering property of 4H-SiC(0001)/SiO$_2$ interface. https://arxiv.org/abs/2506.23912

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