Uncooled CdTe and CdZnTe Based Detectors for γ-Radiation Spectrometry

Abstract

The results of a study of the electrophysical characteristics of the detector single crystals CdZnTe and CdTe obtained from the best domestic (Institute of Rare Metal Industry, Giredmet) and foreign (Acrorad (Japan) and Redlen (Canada)) producers are presented. The values of (μτ)_e in Redlen CdZnTe were 3·10^–3–2·10^–2 cm²/V. It is shown that the transport characteristics μτ of nonequilibrium charge carriers in domestic materials is 3–30 times lower than in the foreign samples. The spectrometric characteristics of the fabricated detectors were studied in the γ-ray energy range 30–662 keV using uncollimated γ-ray sources ¹³³Ba, ²⁴¹Am, ⁵⁷Co, and ¹³⁷Cs. The measured spectra of the amplitude distribution of the pulses from these sources are presented. The best energy resolution for quasi-hemispherical CdZnTe detectors in terms of the energy 662 keV ¹³⁷Cs was 1.7%. The results of these investigations are of interest for monitoring nuclear materials using compact devices with high energy resolution that do not require cooling.