First principles calculation of substitutional oxygen and oxygen-hydrogen complex in gallium arsenide

Walter M. Orellana, A. C. Ferraz

Research output: Contribution to journalArticlepeer-review

Abstract

We report first-principles investigation of the electronic structure, atomic geometry and formation energy of the isolated substitutional oxygen impurity (OAs) and the oxygen-hydrogen pair complex (OAs-H) in GaAs. Our results for OAs in neutral charge state, show an on-site defect with an A1 midgap level occupied with one electron. The OAs-2 charge state shows an off-center displacement of 0.7 Å on the < 111 > direction associated to a JT distorion. The calculated formation energy reveal a negative-U behavior for the doubly negative charge state. For the neutral complex OAs-H, we calculated the total energy and atomic configuration for seven different positions of hydrogen atom with oxygen in the same substitutional site. The lowest energy configuration obtained from our calculations has hydrogen near a bond-center site of OAs-Ga bond, with OAs-H bond length of 1.88 Å and H-Ga of 1.54 Å. The angle between these bonds is found to be 160°. The hydrogen passivation of the impurity level is observed.

Original languageEnglish
Pages (from-to)93-100
Number of pages8
JournalBrazilian Journal of Physics
Volume27
Issue number4
Publication statusPublished - Dec 1997

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint

Dive into the research topics of 'First principles calculation of substitutional oxygen and oxygen-hydrogen complex in gallium arsenide'. Together they form a unique fingerprint.

Cite this