Dopant–dopant interactions in beryllium doped indium gallium arsenide: An ab initio study
Date of Issue2018
School of Physical and Mathematical Sciences
We present an ab initio study of dopant–dopant interactions in beryllium-doped InGaAs. We consider defect formation energies of various interstitial and substitutional defects and their combinations. We find that all substitutional–substitutional interactions could be neglected. On the other hand, interactions involving an interstitial defect are significant. Specially, interstitial Be is stabilized by about 0.9/1.0 eV in the presence of one/two BeGa substitutionals. Ga interstitial is also substantially stabilized by Be substitutionals. Two Be interstitials can form a metastable Be–Be–Ga complex with a dissociation energy of 0.26 eV/Be. Therefore, interstitial defects and defect–defect interactions should be considered in accurate models of Be-doped InGaAs. We suggest that In and Ga should be treated as separate atoms and not lumped into a single effective group III element, as has been done before. We identified dopant-centred states which indicate the presence of other charge states at finite temperatures, specifically, the presence of Beint +1 (as opposed to Beint +2 at 0 K).
Journal of Materials Research
© 2018. Materials Research Society. This paper was published in Journal of Materials Research and is made available as an electronic reprint (preprint) with permission of Materials Research Society. The published version is available at: [http://dx.doi.org/10.1557/jmr.2017.474]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.