3-D position sensitive CdZnTe gamma-ray spectrometers

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Vol. 422; no. 1; pp. 173 - 178
• Main Authors: He, Z., Li, W., Knoll, G.F., Wehe, D.K., Berry, J., Stahle, C.M.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 1999
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/S0168-9002(98)00950-4

Two 3-D position-sensitive room temperature semiconductor γ-ray spectrometers have been built using 1
cm
3 cubic CdZnTe crystals. The lateral coordinates of γ-ray interaction are obtained from the location of the 11(
x)×11(
y) pixellated anodes and the depth (
z) is obtained from the ratio of the signals coming from the cathode and the anode. Energy spectra from 662
keV incident γ-rays have been collected from each of the
11
(x)×11
(y)×20
(z)
voxels in both of the CdZnTe devices. After corrections for electron trapping, the difference of weighting potentials in 3-D, and for the gain variation of the readout circuitry, energy resolutions of 1.70% (11.3
keV) FWHM and 1.84% (12.2
keV) FWHM were obtained at 662
keV γ-ray energy on the first and second detectors, respectively, from the whole bulk for single-pixel events. Possible improvements in the detector performance are discussed.