Thermally activated charge reversibility of gallium vacancies in GaAs

Fadwa El-Mellouhi, Normand Mousseau

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

The dominant charge state for the Ga vacancy in GaAs has been the subject of a long debate, with experiments suggesting -1, -2, or -3 as the best answer. We revisit this problem using ab initio calculations to compute the effects of temperature on the Gibbs free energy of formation, and we find that the thermal dependence of the Fermi level and of the ionization levels lead to a reversal of the preferred charge state as the temperature increases. Calculating the concentrations of gallium vacancies based on these results, we reproduce two conflicting experimental measurements, showing that these can be understood from a single set of coherent local density approximation results when thermal effects are included.

Original languageEnglish
Article number083521
JournalJournal of Applied Physics
Volume100
Issue number8
DOIs
Publication statusPublished - 8 Nov 2006
Externally publishedYes

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gallium
energy of formation
Gibbs free energy
temperature effects
ionization
temperature
approximation

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)
  • Physics and Astronomy(all)

Cite this

Thermally activated charge reversibility of gallium vacancies in GaAs. / El-Mellouhi, Fadwa; Mousseau, Normand.

In: Journal of Applied Physics, Vol. 100, No. 8, 083521, 08.11.2006.

Research output: Contribution to journalArticle

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