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Extended Huckel Semi-Empirical Approach as an Efficient Method for Structural Defects Analysis in 4H-SiC.

ABSTRACT: This paper presents an efficient method to calculate the influence of structural defects on the energy levels and energy band-gap for the 4H-SiC semiconductor. The semi-empirical extended Hückel method was applied to both ideal 4H-SiC crystal and different structures with defects like vacancies, stacking faults, and threading edge dislocations. The Synopsys QuatumATK package was used to perform the simulations. The results are in good agreement with standard density functional theory (DFT) methods and the computing time is much lower. This means that a structure with ca. 1000 atoms could be easily modeled on typical computing servers within a few hours of computing time, enabling fast and accurate simulation of non-ideal atomic structures.

SUBMITTER: Wozny J

PROVIDER: S-EPMC7975987 | biostudies-literature | 2021 Mar

REPOSITORIES: biostudies-literature

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Extended Hückel Semi-Empirical Approach as an Efficient Method for Structural Defects Analysis in 4H-SiC.

Wozny Janusz J Kovalchuk Andrii A Podgorski Jacek J Lisik Zbigniew Z

Materials (Basel, Switzerland) 20210306 5

This paper presents an efficient method to calculate the influence of structural defects on the energy levels and energy band-gap for the 4H-SiC semiconductor. The semi-empirical extended Hückel method was applied to both ideal 4H-SiC crystal and different structures with defects like vacancies, stacking faults, and threading edge dislocations. The Synopsys QuatumATK package was used to perform the simulations. The results are in good agreement with standard density functional theory (DFT) metho ...[more]

PMID: 33800714

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