Silicon carbide detectors for high flux neutron monitoring at near-core locations
Silicon carbide detectors for high flux neutron monitoring at near-core locations
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DOI：
10.1016/j.nima.2019.163110
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发表时间：
2020-02-11
影响因子：
1.4
通讯作者：
Cao, Lei R.
中科院分区：
文献类型：
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作者：
Kandlakunta, Praneeth;Tan, Chuting;Cao, Lei R.
碳化硅（SiC）和氮化镓（GaN）半导体由于其宽带隙和高抗辐射损伤能力，是高温高辐射环境下高通量中子监测的两种候选探测器。碳(C)和硅（Si）的中子弹性散射使SiC对中子具有本质敏感性，而中子通过N-14(N,p)C-14反应与氮(N)的相互作用使GaN具有中子敏感性。在这项研究中，我们研究了基于反应堆的高通量中子监测与自制的SiC探测器，并研究了用GaN探测中子的可行性。作为GaN中子灵敏度的概念验证，我们评估了SiC探测器与氮基（N-based）中子转换器材料的耦合，以及商业购买的AlGaN光传感器。在不同功率水平下，将探测器暴露于研究堆的混合中子-伽马场中，获得了SiC、SiC耦合n基转换器层和AlGaN传感器的光谱响应和原始波形数据。将实验所得的SiC探测器光谱与Geant4蒙特卡罗（MC）模拟结果进行了比较，结果与实测结果一致。用碳化硅探测器原始数据测定的反应器功率与标准补偿离子室（CIC）测定的功率具有良好的相关性。AlGaN传感器显示出良好的结果，传感器响应与反应堆功率之间存在相关性。目前的研究表明，碳化硅具有良好的耐辐射能力，适合用于高通量中子监测。
Silicon carbide (SiC) and gallium nitride (GaN) semiconductors are two detector candidates for high flux neutron monitoring entailing high temperature and high radiation environments owing to their wide band gap and high resistance to radiation damage. While the neutron elastic scattering with carbon (C) and silicon (Si) makes SiC intrinsically sensitive to neutrons, neutron interaction with nitrogen (N) by way of N-14(n,p)C-14 reaction provides neutron sensitivity to GaN. In this study, we investigated reactor-based high flux neutron monitoring with in-house fabricated SiC detectors and studied the feasibility of neutron detection using GaN. As proof-of-concept for GaN neutron sensitivity, we evaluated SiC detectors coupled with nitrogen based (N-based) neutron converter materials, and commercially purchased AlGaN photo sensors. Spectral response as well as raw waveform data from SiC, SiC coupled with N-based converter layers, and AlGaN sensors were acquired while exposing the detectors to a mixed neutron-gamma field of a research reactor at ex-core locations at various power levels. The experimental SiC detector spectra were compared against Geant4 Monte Carlo (MC) simulations, which agreed with the measurement results. The reactor power determined using SiC detector raw data correlated well with that indicated by a standard compensated ion chamber (CIC). The AlGaN sensors showed promising results with a correlation between sensor response and reactor power. The current study demonstrates SiC as a suitable detector for high flux neutron monitoring with good radiation tolerance based on near-core irradiation.