低增益雪崩探测器的数值仿真与辐照效应研究

摘要/Abstract

摘要： 低增益雪崩探测器(LGAD)是新型快速定时探测器,用于克服在重强子辐射下传统硅探测器响应速度慢和抗辐照能力差的问题。使用计算机辅助设计工具(TCAD),构建LGAD的物理模型,对不同温度、电压下LGAD的漏电流、瞬态信号和增益等的变化进行研究。引入一种新的“三陷阱体损伤模型”研究LGAD的抗辐照性能,计算不同中子辐照通量对LGAD相关电学参数的影响。结果表明:LGAD在低温下工作具有更好的性能;辐照后漏电流增大,暗计数率增加,瞬态收集信号变差,增益降低。分析认为是辐照所产生的缺陷影响了LGAD的空间有效电荷和内部电场,通过增大电压和降低温度可以降低这一影响。模拟研究工作得到了不同温度和辐照对探测器性能的影响,对探测器后续的研究和辐照加固设计具有指导意义。

关键词: 低增益雪崩探测器, TCAD仿真, 中子辐照, 辐照模型

Abstract: The Low Gain Avalanche Detector (LGAD) is a new type of fast timing detector designed to overcome the slow response and poor irradiation resistance of conventional silicon detectors under heavy hadron radiation. This study aims to analyze the variation of LGAD related electrical parameters under different temperature and neutron flux irradiation, including leakage current, dark count rate, transient signal, gain, etc. The physical model of LGAD is constructed by using Technology Computer Aided Design (TCAD) tool, and a new “three-trap body damage model” is introduced to study it. The results show that LGAD has better performance at low temperature. After irradiation, the leakage current increases, the dark count rate increases, the transient collection signal deteriorates and the gain decreases. The defects caused by irradiation affect the space effective charge and internal electric field of the LGAD, which can be reduced by increasing the voltage and decreasing the temperature. The effect of different temperature and irradiation on the performance of the detector obtained by this study has some guiding significance for the follow-up research and radiation hardening design of the detector.

Key words: Low Gain Avalanche Detector, TCAD simulation, neutron irradiation, radiation model

中图分类号:

TL81

张翔铭, 孙世峰, 张翱. 低增益雪崩探测器的数值仿真与辐照效应研究[J]. 辐射防护, 2024, 44(3): 265-274.

ZHANG Xiangming, SUN Shifeng, ZHANG Ao. TCAD simulation and irradiation effect study on low gain avalanche detector[J]. RADIATION PROTECTION, 2024, 44(3): 265-274.

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