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Title: Electrical characterization of alpha radiation-induced defects in p-GaAs grown by metal-organic chemical-vapor deposition

Abstract

Investigations of the alpha particle irradiation-induced defects in low-pressure metal-organic chemical-vapor deposition grown p-GaAs have been carried out. By employing deep-level transient spectroscopy, at least seven radiation-induced deep-level defects have been observed in the lower half of the band gap in the temperature range of 12-475 K. Double-correlation deep-level transient spectroscopy measurements show three prominent levels: two known radiation-induced levels namely, H{alpha}1 and H{alpha}5, and one inadvertent center HSA, present before irradiation, to exhibit a significant dependence of thermal emission rate on the junction electric field. For H{alpha}1 and HSA the field-enhanced emission data are well fitted with a Poole-Frenkel model, using a three-dimensional square-well potential with radius r=3.2 and 1.43 nm, respectively. The field effect for H{alpha}5 has been explained by a square-well potential in combination with a phonon-assisted tunneling process. Detailed data on the carrier capture cross section for all three levels have been obtained. The hole capture cross section for the levels H{alpha}1 and H{alpha}5 are found to be temperature independent, while for HSA, the hole capture data show a dependence on temperature. The dependence of hole capture cross section of HSA on temperature has been explained in terms of multiphonon capture mechanism, yielding a capture barriermore » of 0.13 eV and {sigma}({infinity})=1.5x10{sup -14} cm{sup 2}. These analyses lead us to conclude that the levels H{alpha}1 and HSA are associated with a charged center, while the level H{alpha}5 is most likely a substitutional defect in GaAs.« less

Authors:
; ;  [1]
  1. Semiconductor Physics Laboratory, Department of Physics, Quaid-I-Azam University, Islamabad 45320 (Pakistan)
Publication Date:
OSTI Identifier:
20982762
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2710298; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ALPHA PARTICLES; CAPTURE; CHARGE CARRIERS; CHEMICAL VAPOR DEPOSITION; CROSS SECTIONS; DEEP LEVEL TRANSIENT SPECTROSCOPY; ELECTRIC FIELDS; ENERGY GAP; FIELD EMISSION; GALLIUM ARSENIDES; HOLES; IRRADIATION; PHONONS; SQUARE-WELL POTENTIAL; TEMPERATURE RANGE 0000-0013 K; TEMPERATURE RANGE 0013-0065 K; TEMPERATURE RANGE 0065-0273 K; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TUNNEL EFFECT

Citation Formats

Naz, Nazir A., Qurashi, Umar S., and Iqbal, M. Zafar. Electrical characterization of alpha radiation-induced defects in p-GaAs grown by metal-organic chemical-vapor deposition. United States: N. p., 2007. Web. doi:10.1063/1.2710298.
Naz, Nazir A., Qurashi, Umar S., & Iqbal, M. Zafar. Electrical characterization of alpha radiation-induced defects in p-GaAs grown by metal-organic chemical-vapor deposition. United States. doi:10.1063/1.2710298.
Naz, Nazir A., Qurashi, Umar S., and Iqbal, M. Zafar. Thu . "Electrical characterization of alpha radiation-induced defects in p-GaAs grown by metal-organic chemical-vapor deposition". United States. doi:10.1063/1.2710298.
@article{osti_20982762,
title = {Electrical characterization of alpha radiation-induced defects in p-GaAs grown by metal-organic chemical-vapor deposition},
author = {Naz, Nazir A. and Qurashi, Umar S. and Iqbal, M. Zafar},
abstractNote = {Investigations of the alpha particle irradiation-induced defects in low-pressure metal-organic chemical-vapor deposition grown p-GaAs have been carried out. By employing deep-level transient spectroscopy, at least seven radiation-induced deep-level defects have been observed in the lower half of the band gap in the temperature range of 12-475 K. Double-correlation deep-level transient spectroscopy measurements show three prominent levels: two known radiation-induced levels namely, H{alpha}1 and H{alpha}5, and one inadvertent center HSA, present before irradiation, to exhibit a significant dependence of thermal emission rate on the junction electric field. For H{alpha}1 and HSA the field-enhanced emission data are well fitted with a Poole-Frenkel model, using a three-dimensional square-well potential with radius r=3.2 and 1.43 nm, respectively. The field effect for H{alpha}5 has been explained by a square-well potential in combination with a phonon-assisted tunneling process. Detailed data on the carrier capture cross section for all three levels have been obtained. The hole capture cross section for the levels H{alpha}1 and H{alpha}5 are found to be temperature independent, while for HSA, the hole capture data show a dependence on temperature. The dependence of hole capture cross section of HSA on temperature has been explained in terms of multiphonon capture mechanism, yielding a capture barrier of 0.13 eV and {sigma}({infinity})=1.5x10{sup -14} cm{sup 2}. These analyses lead us to conclude that the levels H{alpha}1 and HSA are associated with a charged center, while the level H{alpha}5 is most likely a substitutional defect in GaAs.},
doi = {10.1063/1.2710298},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}