基于碳化硼转换材料的SiC中子探测器研究  

Research of SiC Neutron Detectors Based on Boron Carbide Conversion Materials

作　　者：孙乙文 田立朝 张湘 杨晓虎 徐伟立 胡佳丽 SUN Yiwen;TIAN Lichao;ZHANG Xiang;YANG Xiaohu;XU Weili;HU Jiali(College of Science,National University of Defense Technology,Changsha 410072,China;College of Physics,Sichuan University,Chengdu 610064,China)

机构地区：[1]国防科技大学理学院,湖南长沙410072 [2]四川大学物理学院,四川成都610064

出　　处：《原子能科学技术》2025年第4期920-925,共6页Atomic Energy Science and Technology

基　　金：国家重点研发计划(2023YFC2509301);国家自然科学基金(12175309)。

摘　　要：以SiC-α探头和中子核反应转换材料10B4C为基础的探测器,℃是实现反应堆中子通量测量的新半导体中子探测器方案,其中转换材料的关键在于确定SiC外延层及10B4C转换层厚度。使用Geant4模拟了不同厚度10B4C涂层下热中子和不同能量γ射线在SiC灵敏体积内的能谱,并对不同阈值下热中子探测效率随10B4C涂层厚度的变化关系进行模拟,确定了SiC外延层及10B4C转换层厚度值。拆卸转换层,使用60Co、137Cs、22Na放射源以及中子源,对SiC探测器进行了γ射线探测和热中子探测实验,获得了不同层厚下SiC对热中子探测的能量沉积,得到了最佳的层厚设计,确定了筛除γ信号的合理阈值,验证了方案的可行性。In order to ensure the long-term,stable and safe operation of compact all-solid-state reactors,real-time monitoring of neutron fluxes within the reactor is essential.Neutron flux not only reflects the nuclear activity of the reactor,but is also directly related to the safety and efficiency of the reactor.Among the existing neutron detector technologies,there are some limitations in the application of 3He proportional counting tubes,fission gas ionization chambers,and traditional Si and Ge semiconductor detectors in high-temperature and strong radiation environments,such as the noise of gas detectors will increase significantly in high-temperature environments,which affects the detection accuracy.Although the traditional Si and Ge semiconductor detectors have good energy resolution in low temperature environments,the leakage current becomes larger in high temperature and strong irradiation environments,and the introduced noise will increase significantly,thus limiting their application in extreme environments.As a wide band-gap semiconductor material,SiC detector has the characteristics of large band gap,strong radiation resistance,high breakdown electric field strength and large saturated electron drift velocity,which makes it have excellent high temperature resistance and radiation resistance in extreme environments.The purpose of this study is to design a SiC neutron detector based on the 10B4C conversion layer and optimize its structural parameters to achieve high-precision real-time monitoring of neutron flux in the reactor.The energy spectrum of thermal neutrons in the sensitive volume of 10B4C coating with different thicknesses was simulated by Geant4 simulation software,and the relationship between the energy spectrum of γ rays of different energies in the sensitive volume of SiC and the variation of thermal neutron detection efficiency with the thickness of 10B4C coating under different thresholds were analyzed to determine the optimal thickness values of SiC epitaxial layer and10B4C conversion layer.Com

关 键 词：中子探测 SiC探测器 ^(10)B_(4)C Geant4蒙特卡罗模拟 

分 类 号：TL816[核科学技术—核技术及应用]