Development of the stacked CdTe gamma-ray detector module with high sensitivity and high energy resolution

A gamma-ray detector module with stacked CdTe detector has been developed to be applied to the homeland security where high sensitivity and high energy resolution are required. We introduced the stacked CdTe detector and multi-channel readout ASIC to achieve both high sensitivity and high energy resolution for high energy gamma-ray. Our measurement showed that stacked CdTe detector had the energy resolution of about 1.5 % for 662 keV gamma-ray and higher sensitivity as expected. These results show the flexibility and possibility of the stacked CdTe detector modules in reply to various requirements in gamma-ray detection.