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Title: Enhanced gamma ray sensitivity in bismuth triiodide sensors through volumetric defect control

Abstract

Some of the more attractive semiconducting compounds for ambient temperature radiation detector applications are impacted by low charge collection efficiency due to the presence of point and volumetric defects. This has been particularly true in the case of BiI{sub 3}, which features very attractive properties (density, atomic number, band gap, etc.) to serve as a gamma ray detector, but has yet to demonstrate its full potential. We show that by applying growth techniques tailored to reduce defects, the spectral performance of this promising semiconductor can be realized. Gamma ray spectra from >100 keV source emissions are now obtained from high quality Sb:BiI{sub 3} bulk crystals with limited concentrations of defects (point and extended). The spectra acquired in these high quality crystals feature photopeaks with resolution of 2.2% at 662 keV. Infrared microscopy is used to compare the local microstructure between radiation sensitive and non-responsive crystals. This work demonstrates that BiI{sub 3} can be prepared in melt-grown detector-grade samples with superior quality and can acquire the spectra from a variety of gamma ray sources.

Authors:
; ;  [1]
  1. Nuclear Engineering Program, Department of Materials Science and Engineering, University of Florida, 100 Rhines Hall, Gainesville, Florida 32611 (United States)
Publication Date:
OSTI Identifier:
22590466
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; AMBIENT TEMPERATURE; ATOMIC NUMBER; BISMUTH; CHARGE COLLECTION; COMPARATIVE EVALUATIONS; CRYSTALS; GAMMA RADIATION; GAMMA SOURCES; GAMMA SPECTRA; IODINE COMPOUNDS; KEV RANGE 100-1000; MICROSCOPY; MICROSTRUCTURE; PERFORMANCE; RADIATION DETECTORS; SEMICONDUCTOR MATERIALS; SENSITIVITY

Citation Formats

Johns, Paul M., Baciak, James E., and Nino, Juan C., E-mail: pauljohns@ufl.edu. Enhanced gamma ray sensitivity in bismuth triiodide sensors through volumetric defect control. United States: N. p., 2016. Web. doi:10.1063/1.4962293.
Johns, Paul M., Baciak, James E., & Nino, Juan C., E-mail: pauljohns@ufl.edu. Enhanced gamma ray sensitivity in bismuth triiodide sensors through volumetric defect control. United States. doi:10.1063/1.4962293.
Johns, Paul M., Baciak, James E., and Nino, Juan C., E-mail: pauljohns@ufl.edu. 2016. "Enhanced gamma ray sensitivity in bismuth triiodide sensors through volumetric defect control". United States. doi:10.1063/1.4962293.
@article{osti_22590466,
title = {Enhanced gamma ray sensitivity in bismuth triiodide sensors through volumetric defect control},
author = {Johns, Paul M. and Baciak, James E. and Nino, Juan C., E-mail: pauljohns@ufl.edu},
abstractNote = {Some of the more attractive semiconducting compounds for ambient temperature radiation detector applications are impacted by low charge collection efficiency due to the presence of point and volumetric defects. This has been particularly true in the case of BiI{sub 3}, which features very attractive properties (density, atomic number, band gap, etc.) to serve as a gamma ray detector, but has yet to demonstrate its full potential. We show that by applying growth techniques tailored to reduce defects, the spectral performance of this promising semiconductor can be realized. Gamma ray spectra from >100 keV source emissions are now obtained from high quality Sb:BiI{sub 3} bulk crystals with limited concentrations of defects (point and extended). The spectra acquired in these high quality crystals feature photopeaks with resolution of 2.2% at 662 keV. Infrared microscopy is used to compare the local microstructure between radiation sensitive and non-responsive crystals. This work demonstrates that BiI{sub 3} can be prepared in melt-grown detector-grade samples with superior quality and can acquire the spectra from a variety of gamma ray sources.},
doi = {10.1063/1.4962293},
journal = {Applied Physics Letters},
number = 9,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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