Characteristics of 4H-SiC and diamond detectors for direct fast neutron detection

摘要: Nuclear fusion research is regarded as a key direction for the development of future clean energy, and the precise detection of high-energy neutrons in high-temperature (up to 300°C) environments is particularly important to advance the technological realization of fusion reactors. 4H-SiC and diamond are ideal candidate materials for direct fast neutron detection in such conditions due to their high carbon content and wide-band gap properties. Device structure has great influence on the detection performance and high temperature performance of the detector. In this study, the detection performance of three kinds of detectors based on 4H-SiC and diamond (SiC-SBD, SiC-MSM and Diamond-MSM) under high temperature conditions was investigated, and the influence of device structure and semiconductor material on the high temperature performance was analyzed. The performance of these detectors was evaluated by comparing leakage current, energy resolution, and thermal stability. The results demonstrate that SBD devices exhibit relative better detection accuracy at temperatures below 150°C, but their performance significantly deteriorates as the temperature continue increases, while SiC-MSM shows superior high-temperature stability than SiC-SBD; additionally, Diamond-MSM achieved the best thermal stability over all the test temperature range. At 25℃-350℃, the leakage current of Diamond-MSM remains below 5 nA, while the energy resolution remains below 2.5%@5486 keV. In addition, Diamond-MSM also exhibits the best fast neutron response and excellent counting linearity. This work indicates the great potential of Diamond-MSM device for high-temperature detection applications in nuclear fusion research especially for high-temperature environments.