大规模集成电路中子和γ射线综合电离辐照效应研究

 研究了反应堆中子和γ射线综合辐照环境下CMOS工艺大规模集成电路的电离辐照效应。通过对80C196KC20和PSD501B1两种不同芯片在该环境下开展综合辐照试验,发现总的静态电流增长不明显。对试验结果综合分析得出：在反应堆的综合辐照环境下,中子电离效应较弱,并且由于中子位移效应引起载流子迁移率降低和载流子浓度降低,使得总的静态电流下降,从而抵消中子和γ射线综合电离导致的静态电流增长。     

ICF装置靶场关键材料的辐照效应研究进展

从惯性约束聚变（ICF）装置中靶场关键材料易受辐照损伤、从而限制材料使用寿命和装置稳定运行的现实问题出发,总结归纳了有关不锈钢、铝合金、终端光学组件三大类靶场关键材料的辐照效应研究进展,详细介绍了靶室内高能中子束、γ射线、X射线等高能粒子和射线引起靶室第一壁材料出现烧蚀、中子活化等辐照损伤问题,以及靶室环境对关键材料的影响和防护处理。此外,还阐述了打靶试验中所产生的复杂辐射环境、基频与三倍频激光对靠近靶室的终端光学组件所产生的各类辐照损伤现象和相关作用机理。     

CMOS有源像素传感器辐射损伤对星敏感器星图识别影响机理与识别算法

为分析恶劣空间辐射环境导致星敏感器性能退化、姿态测量精度降低的原因,深入研究了⁶⁰Co-γ射线辐射环境下互补金属氧化物半导体有源像素传感器(complementary metal oxide semiconductor active pixel sensor,CMOS APS)电离总剂量效应对星敏感器星图识别的影响机理.通过搭建外场观星试验系统,实际观测天顶和猎户座天区,经过星图数据采集、星点提取与星图识别等试验流程,获得⁶⁰Co-γ射线辐照后CMOS APS噪声对星图背景灰度均值、识别星点数量的影响机理,并提出一种寻找被辐射噪声湮没星点的识别算法.通过理论推导分别建立了CMOS APS暗电流噪声、暗信号非均匀性噪声和光响应非均匀性噪声与星点质心定位误差的定量关系.研究结果表明⁶⁰Co-γ射线辐照后星敏感器星图背景灰度均值增大、星点识别数量减少, CMOS APS辐照后噪声增大导致星点质心定位误差增大,从而影响星敏感器的姿态定位精度,该研究结果为高精度星敏感器的设计和抗辐射加固提供一定的理论依据.     

不同辐射环境下CMOS器件总剂量测试技术与损伤差异研究

对应用在不同辐射环境下HP4156半导体参数自动化在线测试系统以及脉冲总剂量效应在线测试系统进行了详细的介绍,说明其工作原理和技术指标,并利用这两套测试系统对典型CMOS器件4007在强光一号加速器脉冲硬X射线状态、长脉冲γ射线状态以及⁶⁰Co稳态γ射线状态下开展了不同辐射环境总剂量损伤效应的比较研究, 为今后深入进行此项工作打下了基础.     

稳态、瞬态X射线辐照引起的互补性金属-氧化物-半导体器件剂量增强效应研究

重点开展了稳态、瞬态X射线辐照引起的金属氧化物半导体(CMOS)器件剂量增强效应relative dose enhancement effect(RDEF)研究.通过实验给出辐照敏感参数随总剂量的变化关系,旨在建立CMOS器件相同累积剂量时Χ射线辐照和γ射线辐照的总剂量效应损伤等效关系.在脉冲X射线源dense plasma focus(DPF)装置上,采用双层膜结构开展瞬态翻转增强效应研究,获得了瞬态翻转剂量增强因子.这些方法为器件抗X射线辐照加固技术研究提供了实验技术手段. 关键词： X射线 剂量增强因子 总剂量效应 剂量率效应     

浮栅ROM器件的辐射效应实验研究

浮栅ROM器件的质子和中子辐射效应实验结果表明，其31.9MeV质子和14MeV中子的辐射效应不是单粒子效应，而是一种总剂量效应。浮栅ROM器件的^60Coγ辐照实验验证了这一点，器件出现错误有个注量或剂量阈值。动态监测和静态加电的器件都出现数据错误，且不能用编程器重新写入数据。然而不加电的器件在更高注量的质子或中子或更高剂量的γ辐照下未出现错误，器件刚开始出错时，错误数及错误地址都是不确定的。     

Ti/4H-SiC肖特基势垒二极管抗辐射特性的研究

本文采用γ射线、高能电子和中子对Ti/4H-SiC肖特基势垒二极管(SBD)的抗辐射特性进行了研究.研究发现对于γ射线和1 MeV电子辐照,-30 V辐照偏压对器件的辐照效应没有明显的影响.经过1 Mrad(Si)的γ射线或者1×l0¹³ n/cm²的中子辐照后,Ti/4H-SiC肖特基接触都没有明显退化;经过3.43×10¹⁴ e/cm²的1 MeV电子辐照后Ti/4H-SiC的势垒高度比辐照前轻微下降,这是由于高能 关键词： 碳化硅 肖特基 辐照 偏压     

CMOS有源像素传感器的中子辐照位移损伤效应

为研究空间高能粒子位移损伤效应引起的星用CMOS图像传感器性能退化,对国产CMOS有源像素传感器进行了中子辐照试验,当辐射注量达到预定注量点时,采用离线的测试方法,定量测试了器件的暗信号、暗信号非均匀性、饱和输出电压、像素单元输出电压等参数的变化规律。通过对CMOS图像传感器敏感参数退化规律及其与器件工艺、结构的相关性进行分析,并根据半导体器件辐射效应理论,深入研究了器件参数退化机理。试验结果表明,暗信号和暗信号非均匀性随着中子辐照注量的增大而显著增大,饱和输出电压基本保持不变。暗信号的退化是因为位移效应在体硅内引入大量体缺陷增加了耗尽区内热载流子产生率,暗信号非均匀性的退化主要来自于器件受中子辐照后在像素与像素之间产生了大量非均匀性的体缺陷能级。另外,还在样品芯片上引出了独立的像素单元测试管脚,测试了不同积分时间下像素单元输出信号。     

核辐照后YAG的晶格离子位移

Nd:YAG晶体在X荧光辐照后,晶格常数发生变化[1].LiF单晶在热中子辐照下,衍射面的峰值强度和积分半宽度变化均敏感[2].Si单晶在γ射线辐照下出现离子位移,其作用能主要消耗在碰撞上[3].红宝石激光晶体在γ射线辐照下,输出能量有所提[4].本文主要观察Nd:YAG多晶体辐照前后及恢复过程中的晶面间距的相对异常变化及其可逆性. 一、实验条件及结果 Nd:YAG多晶单相材料是在1650℃空气环境下烧结成的.一个样品的核反应堆的辐照条件为:功率 3000kW,通量中为 1.9× 109中子/cm2s,辐照10秒.男一个样品的辐射条件为:功率3000kW,通量为4.6×109中…     

灵芝酸A对人肝癌细胞的辐射增敏效应的初步研究

本研究旨在初步探讨灵芝酸A(GAA)对人肝癌细胞系HepG2在高LET中子和低LET的γ射线条件下的辐射敏感性的影响及差异。研究中,我们用CCK-8方法检测不同浓度GAA对HepG2增殖抑制作用。选取低浓度(5μmol/L)GAA预处理细胞24 h,分别给予不同剂量的中子辐照或γ射线辐照,分别检测克隆存活率、细胞凋亡和γH2AX蛋白的foci的形成。结果表明:在不加GAA的情况下,高LET中子辐射比低LET的γ射线对细胞产生的凋亡比例高;在添加了GAA后,与未加GAA对照组相比,诱导细胞凋亡的比例明显增加;另外,加GAA处理后,细胞增殖抑制率也随着辐照剂量的增加而增高。即GAA能增加HepG2细胞的辐射敏感性,而在同样GAA剂量下,HepG2细胞对高LET中子辐射比低LET的γ射线更敏感。由此,这项研究说明灵芝酸或可开发成为一种天然辐射增敏剂,从而为癌症特别是肝癌的放疗提供新的辅助治疗方法。     

Synergistic effects of neutron and gamma ray irradiation of commercial CHMOS microcontroller

This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20, which is a 16-bit high performance member of the MCS96 microcontroller family. The electrical and functional tests were made in three irradiation environments: neutron, gamma rays, combined irradiation of neutron and gamma rays. The experimental results show that the neutron irradiation can affect the total ionizing dose behaviour. Compared with the single radiation environment, the microcontroller exhibits considerably more severe degradation in neutron and gamma ray synergistic irradiation. This phenomenon may cause a significant hardness assurance problem.     

Synergistic effects of neutron and gamma ray irradiation of a commercial CHMOS microcontroller

This paper presents the experimental results of a combined irradiation environment of neutron and gamma rays on 80C196KC20,which is a 16-bit high performance member of the MCS96 microcontroller family.The electrical and functional tests were made in three irradiation environments:neutron,gamma rays,combined irradiation of neutron and gamma rays.The experimental results show that the neutron irradiation can affect the total ionizing dose behaviour.Compared with the single radiation environment,the microcontroller exhibits considerably more severe degradation in neutron and gamma ray synergistic irradiation.This phenomenon may cause a significant hardness assurance problem.     

射线检测管道垢厚方法的研究进展

报告了我国开展射线检测原油管道垢厚的研究进展. 介绍了γ射线透射检测垢厚的基本原理、 模拟实验装置及主要研究成果. 研究表明, 研制透射型测垢仪是可行的. 另外, 还给出了南京大学关于表面型中子测垢仪和γ射线测垢仪的初步预研结果.     

探测系统能量分辨在中子能谱数值模拟中的应用

针对中子能谱实验的数值模拟研究中涉及到的探测系统能量分辨问题,基于系统探测伽玛和中子的对应关系以及对伽玛射线的能量分辨率,介绍了一种简便实用的数值模拟方案,利用探测系统对中子、伽玛的光响应对应关系以及其对伽玛的能量分辨率,得到系统对中子的能量分辨率,再进一步把它应用到中子能谱的数值模拟中,并对数值计算结果与相关实验数据进行比较分析。结果表明,该方法可以很好地应用于中子能谱的数值模拟研究。     

Helium-hydrogen synergistic effects on swelling in in-situ multiple-ion beams irradiated steels

The development of reliable fusion energy is one of the most important challenges in this century. The accelerated degradation of structural materials in fusion reactors caused by neutron irradiation would cause severe problems. Due to the lack of suitable fusion neutron testing facilities, we have to rely on ion irradiation experiments to test candidate materials in fusion reactors. Moreover, fusion neutron irradiation effects are accompanied by the simultaneous transmutation production of helium and hydrogen. One important method to study the He-H synergistic effects in materials is multiple simultaneous ion beams (MSIB) irradiation that has been studied for decades. To date, there is no convincing conclusion on these He-H synergistic effects among these experiments. Recently, a multiple ion beam in-situ transmission electron microscopy (TEM) analysis facility was developed in Xiamen University (XIAMEN facility), which is the first triple beam system and the only in-running in-situ irradiation facility with TEM in China. In this work, we conducted the first high-temperature triple simultaneous ion beams irradiation experiment with TEM observation using the XIAMEN facility. The responses to in-situ triple-ion beams irradiation in austenitic steel 304L SS and ferritic/martensitic steel CLF-1 were studied and compared with the results in dual- and single-ion beam(s) irradiated steels. Synergistic effects were observed in MSIB irradiated steels. Helium was found to be critical for cavity formation, while hydrogen has strong synergistic effect on increasing swelling.     

强γ背景下中子针孔成像的点扩展函数

 利用基于Geant4建立起来的针孔成像模型获得了不同偏移量下γ与中子的好事例、能量沉积的比值,并模拟分析了强γ背景对中子针孔成像点扩展函数的影响。研究结果表明:在偏移量小于1 cm时,γ与中子的好事例之比、γ与中子的能量沉积峰值之比以及γ与中子的能量沉积总和之比分别在0.40～0.42,0.63～0.65以及0.46～0.49之间;偏移量大于1 cm时,比值下降明显,γ对中子的影响减小。在同一偏移量下,γ射线的点扩展函数的分布范围要比中子的小,两者叠加后所获得的点扩展函数的分布范围介于两者之间。在一定入射偏移范围内的成像质量优于在针孔中心位置入射时的成像质量。     

Effects of Total-Ionizing-Dose Irradiation on Single-Event Burnout for Commercial Enhancement-Mode AlGaN/GaN High-Electron Mobility Transistors

We investigate the synergism effect of total ionizing dose(TID) on single-event burnout(SEB) for commercial enhancement-mode Al Ga N/Ga N high-electron mobility transistors. Our experimental results show that the slight degradation of devices caused by gamma rays can affect the stability of the devices during the impact of high energy particles. During heavy ion irradiation, the safe working values of drain voltage are significantly reduced for devices which have already been irradiated by ~(60)Co gamma rays before. This could be attributed to more charges trapped caused by ~(60)Co gamma rays, which make Ga N devices more vulnerable to SEB. Moreover, the electrical parameters of Ga N devices after ~(60)Co gamma and heavy-ion irradiations are presented, such as the output characteristic curve, effective threshold voltages, and leakage current of drain. These results demonstrate that the synergistic effect of TID on SEB for Ga N power devices does in fact exist.     

不同顺序中子/γ辐照对双极器件电流增益的影响

利用CFBR-Ⅱ快中子反应堆(中国第二座快中子脉冲堆)和60Co装置开展不同顺序的中子/γ辐照双极晶体管的实验。在集电极-发射极电压恒定条件下,测量了双极晶体管电流增益随集电极电流的变化曲线,研究不同顺序中子/γ辐照对双极晶体管电流增益的影响。分析实验结果发现,集电极-发射极电压一定时,集电极电流极低情况下电流增益退化比较大,随集电极电流增加电流增益逐渐减小;就实验选中的两类晶体管而言,先中子后γ辐照造成双极晶体管电流增益的退化程度大于先γ后中子辐照,而且PNP型晶体管比NPN型晶体管差异更明显。本文进行了双极晶体管电离/位移协同辐照效应相关机理的初步探讨。     

The effect of neutron and gamma irradiation on the dislocation relaxation peak in silver

Summary The internal-friction spectrum has been determined in extremely pure polycrystalline silver crystals after being subjected to neutron and gamma irradiation. The spectra obtained for an applied frequency of 10 MHz show that the mechanical losses due to dislocation relaxation decrease as the doses of neutron and gamma radiation increase. The effect of gamma radiation was found to be more significant than that of neutron irradiation. The relationship between damping neutron and gamma dose was found to be of the formQ _max ⁻¹ α ΛD ^η, where η is equal to −1.2 for neutron and −1.45 for gamma irradiation. The variations of the peak height and width, and temperature of the dislocation relaxation peak as functions of neutron and gamma doses are explained in terms of the pair-kink formation model.