Study On CdZnTe Arrays Detection Technology

With the nuclear radiation detection in a wide range of applications in social production, it is of great significance to research and design high-performance ray detection system. In order to solve the problem of γ ray detector low energy resolution and low detection efficiency at room temperature, a γ ray spectrum detection system is designed with CdZnTe detectors.First, the excellent performance of CDG structure is selected as the detector structure of the detection system, by analyzing CdZnTe detector’s working principle, characteristics and classification, etc. The capacity and resistance feedback charge sensitive preamplifier is selected for its simple structure, and the noise of charge sensitive preamplifier is analyzed, and the input stage JFET circuit structure which has a great impact on noise is adjusted. The charge sensitive preamplifier conversion gain, stability, noise performance achieve the desired state by adjusting the suitable feedback resister and feedback capacitor. Meanwhile the filter forming circuit and the excellent performance baseline restorer are designed. Finally, FPGA-based data acquisition system and programmed threshold screening circuit are designed. The properties of CdZnTe detectors array are tested, and the FPGA array data acquisition system which is used in the array detection is tested.The experiment shows, the designed CdZnTe detectors array has an energy resolution of 5.16% for 241 Am with single-channel. Each channel of the detection system has gotten a better deal with EMC, and has a good output spectrum performance and time stability. Meanwhile the detector is smaller and easy to move, it has good practical value.