Physics:Cadmium zinc telluride
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.[1]
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.[2] CZT can be formed into different shapes for different radiation-detecting applications, and a variety of electrode geometries, such as coplanar grids [3] and small pixel detectors,[4] have been developed to provide unipolar (electron-only) operation, thereby improving energy resolution. A 1 cm3 CZT crystal has a sensitivity range of 30 keV to 3 MeV with a 2.5% FWHM energy resolution at 662 keV.[5] Pixelated CZT with a volume of 6 cm3 can achieve 0.71% FWHM energy resolution at 662 keV and perform Compton imaging.[6]
See also
References
- ↑ Capper, Peter (1994). Properties of Narrow Gap Cadmium-based Compounds. INSPEC. pp. 618. ISBN 0-85296-880-9.
- ↑ 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. doi:10.1016/j.nima.2011.01.144. Bibcode: 2011NIMPA.652..158W.
- ↑ Luke, P.N. (1995). "Unipolar charge sensing with coplanar electrodes -- application to semiconductor detectors". IEEE Transactions on Nuclear Science 42 (4): 207–213. doi:10.1109/23.467848. Bibcode: 1995ITNS...42..207L. https://digital.library.unt.edu/ark:/67531/metadc684991/.
- ↑ Seller, P.; Bell, S.; Cernik, R. J.; Christodoulou, C.; Egan, C. K.; Gaskin, J. A.; Jacques, S.; Pani, S. et al. (2011). "Pixellated Cd(Zn)Te high-energy X-ray instrument". Journal of Instrumentation 6 (12): C12009. doi:10.1088/1748-0221/6/12/C12009. PMID 22737179. Bibcode: 2011JInst...6C2009S.
- ↑ 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. doi:10.3390/s21082884. PMID 33924123. Bibcode: 2021Senso..21.2884V.
- ↑ 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. doi:10.1109/TNS.2011.2175948. Bibcode: 2012ITNS...59..236Z.
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