Experiment and simulation of performance characteristics for pixellated CdZnTe detectors with various thickness

Cadmium zinc telluride (CZT) is one of the preferred materials for the fabrication of X-ray and gamma-ray detector. The purpose of this work was to evaluate limitations of pixellated CdZnTe detectors thickness used under different photon energy and find the best possible compromise for different detector thicknesses. Simulations and experimental investigations of the energy spectrum, energy resolution and photopeak efficiency measured by pixellated CdZnTe detectors have been performed using 241Am and 137Cs irradiation sources. It is concluded that thick CdZnTe provides high energy resolution and photopeak efficiency for high energy of 662 keV, but it suffers from increased tailing and charge loss for low energy of 59.5 keV; while thin devices can provide better performance.