Degradation Under Influence of Radiation Defects of Detector Properties of CdTe and Cd0.9Zn0.1Te Irradiated by Neutrons

  • Alexandr I. Kondrik aNational Science Center “Kharkiv Institute of Physics and Technology”, Kharkiv, Ukraine
  • Gennadij P. Kovtun National Science Center “Kharkiv Institute of Physics and Technology”, Kharkiv, Ukraine; V.N. Karazin Kharkiv National University, Kharkiv, Ukraine
Keywords: detector properties, simulation, CdTe, CdZnTe, neutron irradiation, radiation defects


This work is devoted to the study by computer simulation of the mechanisms of the influence of radiation defects, arising under the influence of neutron irradiation, on the changes in electrical properties: resistivity ρ, electron mobility μn, lifetime of nonequilibrium electrons τn and holes τp in Cd0.9Zn0.1Te and charge collection efficiency η of uncooled ionizing radiation detectors based on this material. Radiation defects, which are corresponded by deep energy levels in the band gap, act as trapping centers of nonequilibrium charge carriers, noticeably affect the degree of compensation by changing ρ of the detector material, the recombination processes, decreasing τn and τp, and also the scattering of conduction electrons, decreasing μn, that ultimately can cause degradation of the charges collection efficiency η. The specific reasons for the deterioration of the electrophysical and detector properties of this semiconductor under the influence of neutron irradiation were identified, and the main factors affecting the increase in the resistivity of Cd0.9Zn0.1Te during its bombardment by low-energy and high-energy neutrons, leading to complete degradation of the recording ability of detectors based on  this materials, were found. The recombination of nonequilibrium charge carriers is noticeably stronger than the decrease in μn affects the degradation of detector properties, therefore, the effect of recombination processes at deep levels of radiation defects on the degradation of τn, τp, and η of detectors based on Cd0.9Zn0.1Te was studied.  A comparative analysis of the properties of Cd0.9Zn0.1Te with the previously studied CdTe:Cl was made. An attempt was made to explain the higher radiation resistance of Cd0.9Zn0.1Te compared to CdTe:Cl under neutron irradiation by the influence of the radiation self-compensation mechanism with participation of deep donor energy levels: interstitial tellurium and tellurium at the site of cadmium. In addition, the rate of recombination at defect levels in Cd0.9Zn0.1Te is, ceteris paribus, lower than in CdTe:Cl due to the smaller difference between the Fermi level and the levels of radiation defects in cadmium telluride. The relationship between the band gaps of Cd0.9Zn0.1Te and CdTe:Cl, the concentration of radiation defects, the Fermi level drift during irradiation, and the radiation resistance of the detectors were also noted. The important role of purity and dopant shallow donor concentration in initial state of the detector material is indicated.


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Penfei Wang, Ruihua Nan, and Zengyun Jian, Journal of Semiconductors, 38, 062002 – 062002-6 (2017),

Lingyan Xu, Wanqi Jie, Gangqiang Zha, Tao Feng, Ning Wang, Shouzhi Xi, Xu Fu, Wenlong Zhang, Yadong Xu, and Tao Wang, Applied Physics Letters, 104, 232109–232109-5 (2014),

A. Castaldini, A. Cavallini, and B. Fraboni, Journal of Applied Physics, 83, 2121–2126 (1997),

N. Krsmanovich, K.G. Lynn, M.H. Weber, R. Tjossem, Th. Gessmann, Cs. Szeles, E.E. Eissler, J.P. Flint, and H.L. Glass, Physical Review B, 62, R16 279 – R16 282 (2000),

D.A. Lamb, C.I. Underwood, V. Barriozet, R. Gwilliam, J. Hall, Mark A. Baker, and Stuart J.C. Irvine, Progress in Photovoltaics, 25, 10059–1067 (2017),

Yu.Yu. Loginov, A.V. Mozzherin, and N.N. Paklin, 21st Int. Scientific Conference Reshetnev Readings-2017. IOP Conf. Series: Materials Science and Engineering, 467, 012007–012007-5 (2019),

Ruihua Nan, Wanqi Jie, Gangqiang Zha, and Bei Wang, Journal of Electronic Materials, 41, 2044–2049 (2012),

S.V. Plyatsko, L.V. Rashkovetskiy, Semiconductors/Physics of the Solid State, 52(3), 322–326 (2018), (in Russian)

Xianf Chen, Hetong Han, Gang Li, and Yi Lu, Nuclear Instruments and Methods in Physics Research B, 394, 97-102 (2017),

A. Cavallini, and B. Fraboni, J. Appl. Phys. 94(5), 3135–31422003 (2003),

A.I. Kondrik, G.P. Kovtun, Tekhnologiya i Konstruirovanie v Elektronnoi Apparature, no. 1-2, 22–29 (2020), . (in Russian)

A.I. Kondrik, G.P. Kovtun, Tekhnologiya i Konstruirovanie v Elektronnoi Apparature, no. 5-6, 43–50 (2019), (in Russian)

G.F. Knoll, Radiation detection and measurement, 4th ed. (John Wiley & Sons, Inc., 2010), p. 864.

B. Fraboni, L. Pasquini, A. Castaldini, and A. Cavallini, Journal of Applied Physics, 106, 093713 – 093713-6 (2009), .

Ruihua Nan, Tao Wang, Gang Xu, Man Zhu, and Wanqi Jie, Journal of Crystal Growth, 451, 150–154 (2016). .

Rui-hua NAN, Wan-qi JIE, Gang-qiang ZHA, Xu-xu BAI, Bei WANG, and Hui YU, Transactions of Nonferrous Metals Society of China, 22, 148–152 (2012),

G.F. Novikov, and N.A. Radychev, Russian Chemical Bulletin, 56(5), 890–894 (2007),

Lei Bao, Gangqiang Zha, Lingyan Xu, Binbin Zhang, Jiangpeng Dong, Yingrui Li, and Wanqi Jie, Materials Science in Semiconductor Processing, 100, 179–184 (2019),

How to Cite
Kondrik, A. I., & Kovtun, G. P. (2020). Degradation Under Influence of Radiation Defects of Detector Properties of CdTe and Cd0.9Zn0.1Te Irradiated by Neutrons. East European Journal of Physics, (3), 85-92.