Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy

S. Fleischer, C. Surya, Y. F. Hu, C. D. Beling, S. Fung, M. Missous

Research output: Contribution to conferencePaper

Abstract

Gallium arsenide grown at low substrate temperature by molecular beam epitaxy has been studied using a variable-energy slow positron beam. As-grown LT-GaAs was found to have a higher concentration of vacancy-related defects (approximately 1017 cm-3) than the semi-insulating substrate. After annealing at 600 °C, the positron S parameter results suggest the formation of clusters which we associate with arsenic precipitation. The lowering of the S parameter at the surface was thought to be due to oxygen and this was confirmed by XPS measurements. For the first time, we have examined aluminum delta-layers using a positron beam and found that the Al-layers can be resolved to depths of at least 1700 angstroms by this method. The lowering of the S parameter after annealing would suggest that the Al forms AlxGa1-xAs, and that the presence of the Al layers may inhibit the diffusion of arsenic, thereby reducing the formation of vacancy-defects.

Original languageEnglish
Pages123-127
Number of pages5
Publication statusPublished - Dec 1 1997
Externally publishedYes
EventProceedings of the 1997 IEEE Hong Kong Electron Devices Meeting - Hong Kong, Hong Kong
Duration: Aug 30 1997Aug 30 1997

Conference

ConferenceProceedings of the 1997 IEEE Hong Kong Electron Devices Meeting
CityHong Kong, Hong Kong
Period8/30/978/30/97

Fingerprint

Scattering parameters
Positrons
Arsenic
Molecular beam epitaxy
Vacancies
Annealing
Defects
Gallium arsenide
Substrates
Temperature
X ray photoelectron spectroscopy
Aluminum
Oxygen

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Fleischer, S., Surya, C., Hu, Y. F., Beling, C. D., Fung, S., & Missous, M. (1997). Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy. 123-127. Paper presented at Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting, Hong Kong, Hong Kong, .

Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy. / Fleischer, S.; Surya, C.; Hu, Y. F.; Beling, C. D.; Fung, S.; Missous, M.

1997. 123-127 Paper presented at Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting, Hong Kong, Hong Kong, .

Research output: Contribution to conferencePaper

Fleischer, S, Surya, C, Hu, YF, Beling, CD, Fung, S & Missous, M 1997, 'Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy' Paper presented at Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting, Hong Kong, Hong Kong, 8/30/97 - 8/30/97, pp. 123-127.
Fleischer S, Surya C, Hu YF, Beling CD, Fung S, Missous M. Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy. 1997. Paper presented at Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting, Hong Kong, Hong Kong, .
Fleischer, S. ; Surya, C. ; Hu, Y. F. ; Beling, C. D. ; Fung, S. ; Missous, M. / Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy. Paper presented at Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting, Hong Kong, Hong Kong, .5 p.
@conference{69546418683b448fae0c0ed1f55d9662,
title = "Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy",
abstract = "Gallium arsenide grown at low substrate temperature by molecular beam epitaxy has been studied using a variable-energy slow positron beam. As-grown LT-GaAs was found to have a higher concentration of vacancy-related defects (approximately 1017 cm-3) than the semi-insulating substrate. After annealing at 600 °C, the positron S parameter results suggest the formation of clusters which we associate with arsenic precipitation. The lowering of the S parameter at the surface was thought to be due to oxygen and this was confirmed by XPS measurements. For the first time, we have examined aluminum delta-layers using a positron beam and found that the Al-layers can be resolved to depths of at least 1700 angstroms by this method. The lowering of the S parameter after annealing would suggest that the Al forms AlxGa1-xAs, and that the presence of the Al layers may inhibit the diffusion of arsenic, thereby reducing the formation of vacancy-defects.",
author = "S. Fleischer and C. Surya and Hu, {Y. F.} and Beling, {C. D.} and S. Fung and M. Missous",
year = "1997",
month = "12",
day = "1",
language = "English",
pages = "123--127",
note = "Proceedings of the 1997 IEEE Hong Kong Electron Devices Meeting ; Conference date: 30-08-1997 Through 30-08-1997",

}

TY - CONF

T1 - Positron studies of arsenic precipitation in low-temperature GaAs grown by molecular beam epitaxy

AU - Fleischer, S.

AU - Surya, C.

AU - Hu, Y. F.

AU - Beling, C. D.

AU - Fung, S.

AU - Missous, M.

PY - 1997/12/1

Y1 - 1997/12/1

N2 - Gallium arsenide grown at low substrate temperature by molecular beam epitaxy has been studied using a variable-energy slow positron beam. As-grown LT-GaAs was found to have a higher concentration of vacancy-related defects (approximately 1017 cm-3) than the semi-insulating substrate. After annealing at 600 °C, the positron S parameter results suggest the formation of clusters which we associate with arsenic precipitation. The lowering of the S parameter at the surface was thought to be due to oxygen and this was confirmed by XPS measurements. For the first time, we have examined aluminum delta-layers using a positron beam and found that the Al-layers can be resolved to depths of at least 1700 angstroms by this method. The lowering of the S parameter after annealing would suggest that the Al forms AlxGa1-xAs, and that the presence of the Al layers may inhibit the diffusion of arsenic, thereby reducing the formation of vacancy-defects.

AB - Gallium arsenide grown at low substrate temperature by molecular beam epitaxy has been studied using a variable-energy slow positron beam. As-grown LT-GaAs was found to have a higher concentration of vacancy-related defects (approximately 1017 cm-3) than the semi-insulating substrate. After annealing at 600 °C, the positron S parameter results suggest the formation of clusters which we associate with arsenic precipitation. The lowering of the S parameter at the surface was thought to be due to oxygen and this was confirmed by XPS measurements. For the first time, we have examined aluminum delta-layers using a positron beam and found that the Al-layers can be resolved to depths of at least 1700 angstroms by this method. The lowering of the S parameter after annealing would suggest that the Al forms AlxGa1-xAs, and that the presence of the Al layers may inhibit the diffusion of arsenic, thereby reducing the formation of vacancy-defects.

UR - http://www.scopus.com/inward/record.url?scp=0031346116&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031346116&partnerID=8YFLogxK

M3 - Paper

SP - 123

EP - 127

ER -