Boron and nitrogen impurities in SiC nanoribbons: an ab initio investigation

Abstract

Listen

Translate article

Using ab initio calculations based on density-functional theory we have performed atheoretical investigation of substitutional boron and nitrogen impurities in silicon carbide(SiC) nanoribbons. We have considered hydrogen terminated SiC ribbons with zigzag andarmchair edges. In both systems we verify that the boron and nitrogen atoms energeticallyprefer to be localized at the edges of the nanoribbons. However, while boron preferentiallysubstitutes a silicon atom, nitrogen prefers to occupy a carbon site. In addition, ourelectronic-structure calculations indicate that (i) substitutional boron and nitrogenimpurities do not affect the semiconducting character of the armchair SiC nanoribbons, and(ii) the half-metallic behavior of the zigzag nanoribbons is maintained in the presenceof substitutional boron impurities. In contrast, nitrogen atoms occupying edgecarbon sites transform half-metallic zigzag nanoribbons into metallic systems.