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Cadmium zinc telluride, (CdZnTe) or CZT, is a compound of cadmium, zinc and tellurium or, more strictly speaking, an alloy of cadmium telluride and zinc telluride. A direct bandgap semiconductor, it is used in a variety of applications, including semiconductor radiation detectors, photorefractive gratings, electro-optic modulators, solar cells, and terahertz generation and detection. The band gap varies from approximately 1.4 to 2.2 eV, depending on composition.

Characteristics

Radiation detectors using CZT can operate in direct-conversion (or photoconductive) mode at room temperature, unlike some other materials (particularly germanium) which require cooling. Their relative advantages include high sensitivity for X-rays and gamma rays, due to the high atomic numbers of Cd and Te, and better energy resolution than scintillator detectors. CZT can be formed into different shapes for different radiation-detecting applications, and a variety of electrode geometries, such as coplanar grids and small pixel detectors, have been developed to provide unipolar (electron-only) operation, thereby improving energy resolution. A 1 cm CZT crystal has a sensitivity range of 30 keV to 3 MeV with a 2.5% FWHM energy resolution at 662 keV. Pixelated CZT with a volume of 6 cm can achieve 0.71% FWHM energy resolution at 662 keV and perform Compton imaging.

See also

• Scintillator
• cadmium telluride
• zinc telluride
• Telluride (chemistry)

References

1. Capper, Peter (1994). Properties of Narrow Gap Cadmium-based Compounds. INSPEC. p. 618. ISBN 0-85296-880-9.
2. Wilson, Matthew David; Cernik, Robert; Chen, Henry; Hansson, Conny; Iniewski, Kris; Jones, Lawrence L.; Seller, Paul; Veale, Matthew C. (2011). "Small pixel CZT detector for hard X-ray spectroscopy". Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 652 (1): 158–161. Bibcode:2011NIMPA.652..158W. doi:10.1016/j.nima.2011.01.144.
3. Luke, P.N. (1995). "Unipolar charge sensing with coplanar electrodes -- application to semiconductor detectors". IEEE Transactions on Nuclear Science. 42 (4): 207–213. Bibcode:1995ITNS...42..207L. doi:10.1109/23.467848. S2CID 64754800.
4. Seller, P.; Bell, S.; Cernik, R. J.; Christodoulou, C.; Egan, C. K.; Gaskin, J. A.; Jacques, S.; Pani, S.; Ramsey, B. D.; Reid, C.; Sellin, P. J.; Scuffham, J. W.; Speller, R. D.; Wilson, M. D.; Veale, M. C. (2011). "Pixellated Cd(Zn)Te high-energy X-ray instrument". Journal of Instrumentation. 6 (12): C12009. Bibcode:2011JInst...6C2009S. doi:10.1088/1748-0221/6/12/C12009. PMC 3378031. PMID 22737179.
5. Verbelen, Yannick; Martin, Peter G.; Ahmad, Kamran; Kaluvan, Suresh; Scott, Thomas B. (2021). "Miniaturised Low-Cost Gamma Scanning Platform for Contamination Identification, Localisation and Characterisation: A New Instrument in the Decommissioning Toolkit". Sensors. 21 (8): 2884. Bibcode:2021Senso..21.2884V. doi:10.3390/s21082884. PMC 8074328. PMID 33924123.
6. Zhang, Feng; Herman, Cedric; He, Zhong; De Geronimo, Gianluigi; Vernon, Emerson; Fried, Jack (2012). "Characterization of the H3D ASIC Readout System and 6.0 cm³ 3-D Position Sensitive CdZnTe Detectors". IEEE Transactions on Nuclear Science. 59 (1): 236. Bibcode:2012ITNS...59..236Z. doi:10.1109/TNS.2011.2175948. S2CID 16381112.

External links

• National Pollutant Inventory - Cadmium and compounds

• Cadmium compounds
• Zinc compounds
• Tellurides
• II-VI semiconductors
• Nonlinear optical materials
• Terahertz technology
• Electro-optical materials
• Ionising radiation detectors