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arXiv · 0809.3119

Band Offsets at Semiconductor-Oxide Interfaces from Hybrid Density Functional Calculations

Audrius Alkauskas·Peter Broqvist·Fabien Devynck·Alfredo Pasquarello
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Abstract

Band offsets at semiconductor-oxide interfaces are determined through a scheme based on hybrid density functionals, which incorporate a fraction $α$ of Hartree-Fock exchange. For each bulk component, the fraction $α$ is tuned to reproduce the experimental band gap, and the conduction and valence band edges are then located with respect to a reference level. The lineup of the bulk reference levels is determined through an interface calculation, and shown to be almost independent of the fraction $α$. Application of this scheme to the Si-SiO$_2$, SiC-SiO$_2$, and Si-HfO$_2$ interfaces yields excellent agreement with experiment.

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Audrius Alkauskas, Peter Broqvist, Fabien Devynck, Alfredo Pasquarello. 2008-09-18. Band Offsets at Semiconductor-Oxide Interfaces from Hybrid Density Functional Calculations. https://doi.org/10.1103/physrevlett.101.106802

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