Molecular-dynamics-based model for the formation of arsenic interstitials during low-temperature growth of GaAs

S. Kunsági-Máté, Carsten Schür, Eszter Végh, T. Marek, Horst P. Strunk

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

The formation of interstitial arsenic defects in low-temperature grown (LT) GaAs layers is examined by temperature dependent, direct trajectory molecular dynamics calculations at semiempirical level. In agreement with earlier ab initio calculations, a metastable interstitial position of an As2 molecule just below the As-rich c (4×4) β reconstructed GaAs(001) surface (characterized by As-As dimers) is obtained. We model this conformation as a precursor state for excess interstitial As in the LT-GaAs layers. Furthermore, a migration layer was found above the surface, where As2 molecules can move practically freely. We identify the hopping of As2 molecules from the interstitial position into this migration layer as the process that controls the experimentally observed dependencies of the excess arsenic content on substrate temperature and arsenic overpressure during growth of LT-GaAs layers.

Original languageEnglish
Article number075315
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume72
Issue number7
DOIs
Publication statusPublished - Aug 15 2005

Fingerprint

Arsenic
Growth temperature
arsenic
Molecular dynamics
interstitials
molecular dynamics
Molecules
Temperature
molecules
overpressure
Dimers
Process control
Conformations
dimers
Trajectories
gallium arsenide
trajectories
Defects
temperature
defects

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Molecular-dynamics-based model for the formation of arsenic interstitials during low-temperature growth of GaAs. / Kunsági-Máté, S.; Schür, Carsten; Végh, Eszter; Marek, T.; Strunk, Horst P.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 72, No. 7, 075315, 15.08.2005.

Research output: Contribution to journalArticle

@article{5f6d6afe4bba4961a68c61fa90727b03,
title = "Molecular-dynamics-based model for the formation of arsenic interstitials during low-temperature growth of GaAs",
abstract = "The formation of interstitial arsenic defects in low-temperature grown (LT) GaAs layers is examined by temperature dependent, direct trajectory molecular dynamics calculations at semiempirical level. In agreement with earlier ab initio calculations, a metastable interstitial position of an As2 molecule just below the As-rich c (4×4) β reconstructed GaAs(001) surface (characterized by As-As dimers) is obtained. We model this conformation as a precursor state for excess interstitial As in the LT-GaAs layers. Furthermore, a migration layer was found above the surface, where As2 molecules can move practically freely. We identify the hopping of As2 molecules from the interstitial position into this migration layer as the process that controls the experimentally observed dependencies of the excess arsenic content on substrate temperature and arsenic overpressure during growth of LT-GaAs layers.",
author = "S. Kuns{\'a}gi-M{\'a}t{\'e} and Carsten Sch{\"u}r and Eszter V{\'e}gh and T. Marek and Strunk, {Horst P.}",
year = "2005",
month = "8",
day = "15",
doi = "10.1103/PhysRevB.72.075315",
language = "English",
volume = "72",
journal = "Physical Review B-Condensed Matter",
issn = "0163-1829",
publisher = "American Physical Society",
number = "7",

}

TY - JOUR

T1 - Molecular-dynamics-based model for the formation of arsenic interstitials during low-temperature growth of GaAs

AU - Kunsági-Máté, S.

AU - Schür, Carsten

AU - Végh, Eszter

AU - Marek, T.

AU - Strunk, Horst P.

PY - 2005/8/15

Y1 - 2005/8/15

N2 - The formation of interstitial arsenic defects in low-temperature grown (LT) GaAs layers is examined by temperature dependent, direct trajectory molecular dynamics calculations at semiempirical level. In agreement with earlier ab initio calculations, a metastable interstitial position of an As2 molecule just below the As-rich c (4×4) β reconstructed GaAs(001) surface (characterized by As-As dimers) is obtained. We model this conformation as a precursor state for excess interstitial As in the LT-GaAs layers. Furthermore, a migration layer was found above the surface, where As2 molecules can move practically freely. We identify the hopping of As2 molecules from the interstitial position into this migration layer as the process that controls the experimentally observed dependencies of the excess arsenic content on substrate temperature and arsenic overpressure during growth of LT-GaAs layers.

AB - The formation of interstitial arsenic defects in low-temperature grown (LT) GaAs layers is examined by temperature dependent, direct trajectory molecular dynamics calculations at semiempirical level. In agreement with earlier ab initio calculations, a metastable interstitial position of an As2 molecule just below the As-rich c (4×4) β reconstructed GaAs(001) surface (characterized by As-As dimers) is obtained. We model this conformation as a precursor state for excess interstitial As in the LT-GaAs layers. Furthermore, a migration layer was found above the surface, where As2 molecules can move practically freely. We identify the hopping of As2 molecules from the interstitial position into this migration layer as the process that controls the experimentally observed dependencies of the excess arsenic content on substrate temperature and arsenic overpressure during growth of LT-GaAs layers.

UR - http://www.scopus.com/inward/record.url?scp=33644960388&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33644960388&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.72.075315

DO - 10.1103/PhysRevB.72.075315

M3 - Article

AN - SCOPUS:33644960388

VL - 72

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 0163-1829

IS - 7

M1 - 075315

ER -