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Title: Point defect balance in epitaxial GaSb

Abstract

Positron annihilation spectroscopy in both conventional and coincidence Doppler broadening mode is used for studying the effect of growth conditions on the point defect balance in GaSb:Bi epitaxial layers grown by molecular beam epitaxy. Positron annihilation characteristics in GaSb are also calculated using density functional theory and compared to experimental results. We conclude that while the main positron trapping defect in bulk samples is the Ga antisite, the Ga vacancy is the most prominent trap in the samples grown by molecular beam epitaxy. The results suggest that the p–type conductivity is caused by different defects in GaSb grown with different methods.

Authors:
; ; ; ;  [1]; ;  [2];  [3]
  1. Department of Applied Physics, Aalto University, P.O. Box 14100, FIN-00076 Aalto Espoo (Finland)
  2. Department of Microtechnology and Nanoscience, Chalmers University of Technology, 41296 Göteborg (Sweden)
  3. (China)
Publication Date:
OSTI Identifier:
22310955
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 8; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ANNIHILATION; BALANCES; CRYSTAL GROWTH; DENSITY FUNCTIONAL METHOD; DOPPLER BROADENING; GALLIUM ANTIMONIDES; LAYERS; MOLECULAR BEAM EPITAXY; POINT DEFECTS; POSITRONS; SPECTROSCOPY; TRAPS; VACANCIES

Citation Formats

Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi, Slotte, J., Makkonen, I., Kujala, J., Tuomisto, F., Song, Y., Wang, S., and State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050. Point defect balance in epitaxial GaSb. United States: N. p., 2014. Web. doi:10.1063/1.4894473.
Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi, Slotte, J., Makkonen, I., Kujala, J., Tuomisto, F., Song, Y., Wang, S., & State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050. Point defect balance in epitaxial GaSb. United States. doi:10.1063/1.4894473.
Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi, Slotte, J., Makkonen, I., Kujala, J., Tuomisto, F., Song, Y., Wang, S., and State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050. Mon . "Point defect balance in epitaxial GaSb". United States. doi:10.1063/1.4894473.
@article{osti_22310955,
title = {Point defect balance in epitaxial GaSb},
author = {Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi and Slotte, J. and Makkonen, I. and Kujala, J. and Tuomisto, F. and Song, Y. and Wang, S. and State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050},
abstractNote = {Positron annihilation spectroscopy in both conventional and coincidence Doppler broadening mode is used for studying the effect of growth conditions on the point defect balance in GaSb:Bi epitaxial layers grown by molecular beam epitaxy. Positron annihilation characteristics in GaSb are also calculated using density functional theory and compared to experimental results. We conclude that while the main positron trapping defect in bulk samples is the Ga antisite, the Ga vacancy is the most prominent trap in the samples grown by molecular beam epitaxy. The results suggest that the p–type conductivity is caused by different defects in GaSb grown with different methods.},
doi = {10.1063/1.4894473},
journal = {Applied Physics Letters},
number = 8,
volume = 105,
place = {United States},
year = {Mon Aug 25 00:00:00 EDT 2014},
month = {Mon Aug 25 00:00:00 EDT 2014}
}
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