Cadmium zinc telluride selenide (CdZnTeSe) is emerging as a promising semiconductor material for low-cost production of nuclear and radiological detection systems capable of operating at room temperature. This paper presents studies of the fabrication process and detector response for gamma-ray detectors produced from high-quality CdZnTeSe crystals grown by the traveler heater method (THM). The resistivity of the CdZnTeSe is on the order of 10 GΩ-cm. The electron mobility-lifetime (μτ) product characterizing the charge-transport properties is on the order of 0.001 square-cm per volt. Energy resolutions as good as 6.5% FWHM for the 59.5-keV gamma-peak of 241 Am were recorded for planar detectors with gold contacts.
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Characterization of CdMnTe Planar Nuclear Detectors Grown by Vertical Bridgman Technique
Cadmium manganese telluride (CdMnTe) crystals are expected to be homogeneous in structure due to the segregation coefficient of Mn in CdTe, which is about 1.0. This could translate in the growth of large-volume CdMnTe crystals free of defects that currently limit X-ray and gamma-ray detection efficiencies. The present characterization experiments show results on CdMnTe planar detectors grown by the vertical Bridgman technique. The CdMnTe crystal used in the experiments was mostly free of tellurium inclusions and high angle grain boundaries. We recorded an energy resolution of 9.2% FWHM for the 59.5-keV gamma-peak of Am-241 for the planar detector. We also resolved peaks at energies below the 59.5-keV peak.
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- Award ID(s):
- 1818732
- PAR ID:
- 10184945
- Date Published:
- Journal Name:
- 2019 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC)
- Page Range / eLocation ID:
- 1 to 3
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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