Detailed modelling of pixellated CdZnTe detectors for an accurate performance characterization of a multi-modality imaging system

Room temperature semiconductor detectors, such as CdZnTe (CZT), are promising candidates for the design and development of a true integrated multimodality imaging system. However, hitherto no detailed analysis of the real potential of such a CZT-based canner has been carried out. In this work we report the modifications and developments implemented to incorporate the first of its kind accurate modelling of pixellated CZT detectors in different configurations within the Geant4 application for tomographic emission (GATE) simulation platform. These models are required for an accurate simulation and a precise future analysis of the expected overall performance of the scanner. The quantitative assessment of the simulated data will result in an optimum pixellated CZT detector design with specifications that compensate transport properties in the crystal but also meet the requirements for an integrated PET/SPECT/CT multimodal system.