Papers by Keyword: CdZnTe Detector

Abstract: Cadmium zinc telluride (CZT) material is one of the preferred materials for the fabrication of X-ray and gamma-ray detector. In this paper, it is presented an experimental detector system based on pixellated CZT semiconductor detector. The aim of this study is to get the photon energy suitable for different thickness detector, different photon energy acts on pixel CdZnTe detector of different thickness. We can obtain the energy spectrum estimation, energy resolution and peak efficiency by the experiment and simulation with the radiation source of 241Am and 137Cs acting on pixel CdZnTe detector. From experiment results, it can be found that at the high energy of ⁶⁶²keV the thicker CdZnTe detector is high. The characteristic of detector is better at the low energy when the detector thickness is thinner.

Abstract: Currently, many semiconductor compounds, particularly Cd1-xZnxTe, have attracted attention for applications in detection of radiation, due to the very good resolution without cryogenic cooling (a 1.3 keV-FWHM at the 122 keV line from 57Co is reported for some detectors). In this study the properties of a zinc doped cadmium telluride detector mounted on a thermoelectric cooler (Amptek Inc., model XR-100T-CZT) were studied. The detection system is based on a Cd0.9Zn0.1Te crystal of 3x3x2 mm, which operates at approximately -21°C and uses a rise time discrimination (RTD) circuit to improve the energy resolution. Although the quantum efficiency of this compound is very high, the small dimensions of the crystal limit its use to low energy photons (some hundreds of keV). Because of the carrier trapping characteristics of CZT, the experimental determination of the response function is essential. In this work it was measured in the range of energies from 10 to 400 keV, employing gamma rays and fluorescence x-rays from different sources (57Co, 133Ba, 152Eu and 241Am). In spite of the experimental difficulties, the x-ray escape fraction was also evaluated, making it possible the correction of the distortion it causes in the measured spectra. Measurements of x-ray spectra produced by a tungsten tube operating at small currents were carried out, and the stripping procedure was performed, taking into account the two contributions (efficiency and escape fraction). Results obtained point to the feasibility of use of this detector for in-situ diagnostic x-ray spectroscopy, provided that low intensity beams are available.