变组分变掺杂p-i-n型AlGaAs/GaAs微结构中子探测器性能表征  

Performance Characterization of p-i-n AlGaAs/GaAs Microstructure Neutron Detector with Variable Component and Variable Doping

作　　者：周青 邹继军[1] 叶鑫 张明智 Zhou Qing;Zou Jijun;Ye Xin;Zhang Mingzhi(Ministry of Education Engineering Research Center of Nuclear Technology Application,East China University of Technology,Nanchang 330013,China)

机构地区：[1]东华理工大学核技术应用教育部工程研究中心,南昌330013

出　　处：《机电工程技术》2023年第1期14-17,71,共5页Mechanical & Electrical Engineering Technology

基　　金：国家自然科学基金资助项目(编号:12275049);江西省重点研发计划项目(编号:20212BBG73012)。

摘　　要：制备了一种在p-i-n型AlGaAs/GaAs材料上刻蚀微沟槽的中子探测器。通过MOCVD技术生长了变组分变掺杂的p-i-n型AlGaAs/GaAs,使用ICP技术在材料上刻出微沟槽,沟槽宽度为25μm,深度为10μm。探测器的探测面积为4 mm^(2),沟槽宽度和间距为1∶1,呈周期性排列,在沟槽中填充中子转换材料探测热中子信号。通过对平面和微结构p-i-n型AlGaAs/GaAs探测器的电学特性、α粒子以及中子探测性能的比较分析,发现两者在电学特性和α粒子能量分辨率方面有较大差别。5 V偏压下平面型和微结构AlGaAs/GaAs探测器的漏电流分别是-0.024 1μA、-0.627μA,两者相差近30倍,这是由于微结构刻蚀了部分异质结导致器件表面漏电流增加。0 V偏压下微结构探测器α粒子能量分辨率比平面型也有些许恶化,但在热中子探测上微结构效果更佳,中子总计数微结构比平面型多一倍。微结构降低了探测器的自吸收问题,同时增大了探测器的中子接触面积,在热中子探测上应用前景广阔。A neutron detector etching microgrooves on p-i-n AlGaAs/GaAs material had been fabricated. The p-i-n type AlGaAs/GaAs with variable components and variable doping were grown by MOCVD technology, and the micro-grooves with width of 25 μm and depth of 10 μm were cut into the material by ICP technology. The detection area of the detector was 4 mm^(2), the width and spacing of the grooves were 1∶1, and the grooves were arranged periodically. The grooves were filled with neutron conversion materials to detect thermal neutron signals. By comparing and analyzing the electrical characteristics, α-particle and neutron detection performance of planar and microstructure p-i-n AlGaAs/GaAs detectors, it was found that there were great differences in electrical characteristics and α-particle energy resolution between them. Under 5 V bias, the leakage current of planar AlGaAs/GaAs detector and groove AlGaAs detector were-0.024 1 μA and-0.627 μA,respectively, which were nearly 30 times different. This was because the microstructure etched part of the hetero junction, which leaded to the increase of the leakage current on the device surface. The energy resolution of α particle in the micro-structure detector was slightly worse than that in the plane type under 0 V bias, but the effect of the groove type was better in thermal neutron detection, and the total number of neutrons in the micro-structure was twice as much as that in the plane type. The microstructure reduces the self-absorption problem of the detector, and increases the neutron contact area of the detector, so it has a broad application prospect in thermal neutron detection.

关 键 词：ALGAAS 中子探测器 微结构 6LiF 热中子 

分 类 号：TN36[电子电信—物理电子学]