Abstract In order to reveal radiation-induced characteristics of CdTe detectors, we present the irradiation effects between bulk and detector properties under radiation levels of 10 5 R/h gamma-rays. Drift mobilities both for holes and electrons are remarkably reduced after irradiation and then charge transport is dominated by appearances of an electron-trap level at E c − 0.5 eV and a hole-trap level at E v + 0.14 eV. The fwhm energy resolution acquired at 278 K with a detector produ from undoped THM crystals obtained under a controlled Cd over-pressure is approximately 8 keV for 59.5 keV gamma rays from 241 Am and 12 keV for 122 keV gamma rays from 57 Co. The effect due to successive irradiations of 60 Co gamma-rays markedly degraded the output pulse-height spectra where ultimately the 59.5 keV and 122 keV photopeaks could not be discerned. Following annealing of about 600 K, the pulse-height spectrum recovers almost to the preirradiation value. This agrees with the recovery stage of the electron-trap level at E c − 0.5 eV.
[1]
R. Bell,et al.
Characterization of the Transport Properties of Halogen-Doped CdTe Used for Gamma-Ray Detectors
,
1974
.
[2]
K. Zanio.
Use of various device geometries to improve the performance of CdTe detectors
,
1977
.
[3]
L. T. Jones.
The use of cadmium telluride γ spectrometers in monitoring activity deposited in nuclear power stations
,
1977
.
[4]
M. Lorenz,et al.
Some Properties of a Double Acceptor Center in CdTe
,
1964
.
[5]
R. Bell.
Binding energy of an electron to a three-defect-complex in CdTe
,
1975
.
[6]
G. Armantrout,et al.
Theoretical Band Structure Analysis on Possible High-Z Detector Materials
,
1975,
IEEE Transactions on Nuclear Science.
[7]
T. Taguchi,et al.
Excitonic emission in cadmium telluride
,
1975
.