CdZnTe (CZT) single crystals were grown by a modified vertical Bridgman method. After the growth was completed, the crystals were annealed at a constant temperature for a long time. Infrared microscope, I-V characteristic curves, and multi-channel spectrometer were employed to analyze Te inclusions distribution in the crystal, electrical resistivity and spectroscopy response of CZT wafers. The results show that in-situ annealing can greatly decrease concentration of Te inclusions, and most of the Te inclusion sizes are less than 5 μm. In addition, electrical resistivity of CZT is increased from 4.54×108 to 3.73×1010 after annealing. The 241Am@59.5 keV keV keV-ray pulse height spectra of CZT crystal after in-situ annealing reaches 7.29%.
ZHANG Thao, MIN Jia-Hua, LIANG Xiao-Yan, TENG Jia-Qi, SHI Bin-Bin, WANG Lin-Jun
. Effect of In-situ Annealing on Properties of CdZnTe Crystals[J]. Journal of Shanghai University, 2014
, 20(6)
: 701
-706
.
DOI: 10.3969/j.issn.1007-2861.2014.01.027
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