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arXiv · 2010.14106

Influence of surface structure and strain on indium segregation in InGaAs: a first-principles investigation

Soumya S. Bhat·Satadeep Bhattacharjee·Jung-Hae Choi·Seung-Cheol Lee
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Abstract

The surface segregation of indium atoms in InGaAs is investigated using first-principles calculations based on density functional theory. Through the calculation of segregation energies for (100), (110), and (111) surfaces of GaAs we analyze the decisive role of surface orientation on indium segregation. Further, our calculations reveal that the variation of segregation energy as a function of applied strain strongly depends on surface reconstruction. Obtained segregation energy trends are discussed in light of atomic bonding probed via integrated crystal orbital Hamilton population. Results presented in this paper are anticipated to guide experimental efforts to achieve control on In segregation by managing As-flux along with the application of strain.

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Soumya S. Bhat, Satadeep Bhattacharjee, Jung-Hae Choi, Seung-Cheol Lee. 2020-10-27. Influence of surface structure and strain on indium segregation in InGaAs: a first-principles investigation. https://arxiv.org/abs/2010.14106

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