新型MSM结构砷化镓半导体探测器的性能

研究一种新型双金属接触GaAs半导体探测器的性能,测量了²⁴¹Am 5.48MeVα粒子、⁵⁷Co 122keV的光子和⁹⁰Sr 2.27MeVβ粒子的最小电离粒子谱,比较了一个3×3mm²的GaAs芯片在经过¹³⁷Cs 662keV光子约1300rad辐照前后的电荷收集效率和能量分辨率.测量结果显示这种新型金属─半导体─金属(MSM)结构的半导体探测器不仅在室温下对各种粒子具有良好的探测能力,而且具有很好的抗辐照性能.     

用于质子和伽马射线探测的金刚石薄膜探测器的辐照性能

 研制出CVD金刚石薄膜探测器,在国家串列加速器和⁶⁰Co稳态辐射源上分别完成了该探测器对9 MeV质子束流和1.25 MeV γ射线的辐照性能研究。结果表明:该探测器在9 MeV质子照射累积强度达到10¹³ cm^-2时,探测器信号电荷收集效率减小量低于3.5%,辐照前后探测器暗电流没有明显变化。计算得到9 MeV质子对该探测器的损伤系数为1.3×10^-16 μm^-1·cm²。由于γ射线与金刚石作用产生的电子起到了填补缺陷的作用,探测器信号电荷收集效率随γ射线照射剂量的增加略有增加,在γ射线累积照射量达到10.32 C/kg时,其增幅小于0.7%。说明金刚石薄膜探测器具有较高耐辐照强度,适用于高强度辐射测量领域。     

用于质子和伽马射线探测的金刚石薄膜探测器的辐照性能

研制出CVD金刚石薄膜探测器,在国家串列加速器和60Co稳态辐射源上分别完成了该探测器对9 MeV质子束流和1.25 MeV γ射线的辐照性能研究。结果表明:该探测器在9 MeV质子照射累积强度达到1013 cm-2时,探测器信号电荷收集效率减小量低于3.5%,辐照前后探测器暗电流没有明显变化。计算得到9 MeV质子对该探测器的损伤系数为1.3×10-16 μm-1·cm2。由于γ射线与金刚石作用产生的电子起到了填补缺陷的作用,探测器信号电荷收集效率随γ射线照射剂量的增加略有增加,在γ射线累积照射量达到10.32 C/kg时,其增幅小于0.7%。说明金刚石薄膜探测器具有较高耐辐照强度,适用于高强度辐射测量领域。     

电子辐照下GaAs/Ge太阳电池载流子输运机理研究

通过地面模拟辐照试验获得不同能量电子辐照下GaAs/Ge太阳电池电学参数退化的基本规律, 在此基础上使用PC1 D模拟程序分析太阳电池内部的载流子输运机理, 建立不同能量的电子辐照下GaAs/Ge太阳电池中多数载流子浓度和少数载流子扩散长度随辐照粒子注量变化的基本规律. 研究结果表明: 多数载流子浓度和少数载流子扩散长度均随入射电子注量的增大而减小, 多数载流子去除率和少数载流子扩散长度损伤系数均随电子能量的增高而增大, 多数载流子去除效应和少数载流子扩散长度缩短分别是电池开路电压和短路电流退化的主要原因.     

位移损伤剂量法评估空间GaAs/Ge太阳电池辐照损伤过程

本文针对GaAs/Ge太阳电池,利用位移损伤剂量法研究了其在轨服役条件下的性能退化行为.首先在地面模拟辐照环境中,试验获得了在不同能量的电子和质子辐照下的电池性能随辐照注量的退化行为.基于上述实验结果以及计算获得的带电粒子在电池中的非电离能量损失(NIEL)获得了不同能量电子辐照位移损伤的等效指数n为1.7,电子损伤剂量转化为质子损伤剂量等效系数为5.2,并进一步建立了电池性能随位移损伤剂量的退化方程.利用该方法对国产GaAs/Ge太阳电池在500,22000和36000 km轨道带电粒子辐 关键词： GaAs/Ge太阳电池 辐照损伤 带电粒子 位移损伤剂量     

MSM结构Mg0.2Zn0.8O可见盲光电探测器

采用射频磁控溅射,通过传统的紫外曝光和湿法腐蚀的方法,制备了不同电极间距的金属-半导体-金属(MSM)结构Mg0.2Zn0.8O可见盲光电探测器.研究了器件的暗电流和响应度随电极间距的变化关系,当施加的电压没有达到贯穿电压的时候,暗电流和响应度均随着电极间距的增加而减小,并对其具体的机制进行了研究.     

GaAs基谐振腔增强型光电探测器

本文报道了利用MBE和MOCVD方法生长外延材料并制作出GaAs基谐振腔增强型光电探测器，进行理论分析和实验研究的结果。     

GaAs：Cr探测器中子辐照改性研究

介绍了一种新型脉冲辐射探测器以及提高其性能的一种方法,并报告了探测器性能与中子积分通量关系的实验结果。     

4H-SiC探测器的γ辐照影响研究

为研究4H-SiC探测器的抗γ辐照性能,使用40万Ci级的⁶⁰Co源对4H-SiC探测器进行了数次辐照,累积辐照剂量最大为1 MGy(Si),并在辐照后对4H-SiC的性能进行了测试。随着累积辐照剂量增加,4H-SiC探测器的正向电流增大,而反向电流恰好相反;根据4H-SiC探测器的正向I-V曲线可提取理想因子和肖特基势垒,理想因子从1.87增加到2.18,肖特基势垒从1.93 V减小至1.69 V;4H-SiC探测器对²⁴¹Am源产生的α粒子进行探测时,探测器的电荷收集率从95.65%退化到93.55%,测得能谱的能量分辨率由1.81%退化到2.32%。4H-SiC探测器在受到1 MGy(Si)的γ辐照后,与未受到辐照时相比,在探测能量为5.486 MeV的α粒子时能量分辨率和电荷收集率仅退化了28.18%和2.2%,仍具备优良的探测性能。     

双束质子辐照砷化镓光电导探测器的I-V特性

对用能量为7.5MeV和20MeV,注量为1011～1013cm-2的质子辐照后的砷化镓材料制作的光电导探测器的光电流和暗电流进行了测试,并由此推得电导率的变化。结果表明,经过能量为7.5MeV的质子改性后的砷化镓探测器相对于未改性的附加光电导率Δσ减少,而且随着辐照注量的增加而越小,而对于先用能量为20MeV质子辐照后再用能量为7.5MeV的质子辐照的砷化镓材料制作的探测器,其附加光电导率Δσ的减少则更为明显。对上述现象进行了分析,并根据其相应关系预测了该种探测器的响应时间、灵敏度、拖尾现象及受X射线激发的输出脉冲的后延的变化情况。     

Quantum-Sensitive Ionizing Radiation Detectors Compensated by Gallium Arsenide

The state-of-the art of and outlook for semiconductor GaAs ionizing radiation detectors are discussed. A comparative analysis of the most essential features of detectors based on semi-insulating GaAs is performed.     

塑料闪烁体的辐照特性

利用⁶⁰Co放射源分别对3种塑料闪烁体(BC-408, EJ-200, BC-404)进行辐照损伤研究, 比较辐照前后的透射谱、发射谱及光产额的变化, 发现3种闪烁体在低剂量具有较好的抗辐照性能; 当照射剂量超过1.44×10⁴Gy时,透射谱明显变坏, 光输出减少很严重, 但发射谱却保持不变.     

Radiography with Solid State Nuclear Track Detectors

The investigation of localisation is counted among the typical and important applications of nuclear track recorders. In this paper, after a comparison of the most important features of nuclear track recorders a system of their applications is given. On the grounds of information obtained from the tracks, eight groups of applications can be distinguished. One of them represents the four geometrical situations of the different types of radiography.

Taking radiography into account in the wider sense, as an investigation of localisation, then several cases of special localization tasks are known, which can be classified into two further groups of applications of track detectors. A survey of the applications of solid slate nuclear track detectors for all kinds of radiography is given on the basis of this definition of localisation experiments.     

Comparison of Makrofol-E and CR-39 as Solid State Nuclear Track Detectors

A comparison of the etching parameters as well as the neutron response for Makrofol-E and CR-39 was considered as solid state nuclear track detectors. The calculated sensitivity for both detectors was compared with the measured one. It is found that CR-39 has higher response to fast neutrons than Makrofol-E. The response increase due to decreasing the rate of layer removed and increasing the etch-pits per unit area.     

Structural and Thermodynamic Properties of Gallium Arsenide with Hexagonal Wurtzite Structure from First-Principles Analysis

A first-principles plane wave method with the ultrasoft pseudopotential scheme in the frame of the generalized gradient approximation （GGA） is performed to calculate the lattice parameters, the bulk modulus Bo and its pressure derivative B~o of the hexagonal wurtzite GaAs （w-GaAs） by the Cambridge serial total energy package （CASTEP）. Our calculations show that the most stable structure of the w-GaAs corresponds to the axial ratio c/α = 1.651 and the internal parameter u = 0.374, consistent with other theoretical results. Also, the thermodynamic properties of the w-GaAs are investigated from the quasi-harmonic Debye model. The dependences of the normalized lattice parameters α/α0, c/c0, the axial ratio c/α, the normalized volume V/V0, the heat capacity Cv and the thermal expansion α on pressure P and temperature T are also obtained successfully.     

新型CZT半导体X射线和g射线探测器研制与应用展望

CdZnTe(CZT)半导体是一种性能优异的室温X射线和γ射线探测材料,在环境监测、医学诊断、工业无损检测、安全检查、空间科学等众多领域有广泛的应用前景。文章简要介绍了CZT探测器的基本工作原理和性能评价指标,阐述了CZT晶体物理性能对CZT探测器性能的影响规律和CZT探测器的模拟与设计方法。CZT半导体探测器的应用与发展前景广阔,为此需要重点开展高质量、低成本的CZT晶体生长研究,CZT探测器的设计与制备以及辐射探测整机系统的设计与开发。     

MSM结构ZnO紫外探测器的制备与性质

采用射频磁控溅射在石英衬底上制备了c轴择优取向的ZnO薄膜,利用蚀刻技术制备了MSM结构的光导型紫外探测器。在3V偏压下,器件的暗电流小于250nA,光响应峰值在370nm,响应度是0.34A/W。其紫外(360nm)与可见光(420nm)的抑制比为4个数量级。器件的光响应时间上沿仅为20ns。     

Analyse of Corrections during Measurements of Charge of a Semiconductor Detector

The amplitude of signals coming from a semiconductor detector depends on the a amplifier system filter networks, detector physical properties and energy of particles measured. The absolute measuring of detector charge requires an analysis of the influence of the mentioned parameters upon the measuring system reaction. The paper gives the theoretical concepts and correction diagrams for the optimum filter networks of CR-RC and CR-(RC)² tapes taking into consideration the existence of an undesirable integrating constant of the charge sensitive preamplifier. The application of the presented diagrams increases the accuracy and helps checking the obtained results by a pulse generator.