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

Journal Article · Mon Aug 29 04:00:00 EDT 2016 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4962293· OSTI ID:22590466

Johns, Paul M.; Baciak, James E.

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.

• OSTI ID: 22590466
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 9 Vol. 109; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

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