MOSFET功率管器件单粒子烧毁效应(SEB)截面测量

对MOSFET功率管进行了16^O、35^Cl、79^Br离子及高剥离态^127I离子的单粒子烧毁(SEB)效应截面测量，得到了SEB截面相对于线性能量转移(LET)值的曲线。对两种类型10片MOSFET功率管器件的SEB截面进行了测量。研究了器件在不同工作条件下，如不同的漏源电压VDs和栅源电压KGs条件下的SEB效应。在相同条件下，^127I的SEB截面比^79Br的高近两个量级。     

用~(252)Cf裂片源研究单粒子烧毁和栅穿效应的方法

建立了2 5 2 Cf裂片源模拟空间重离子的单粒子烧毁 (SEB)和单粒子栅穿 (SEGR)效应的实验方法和测试装置 ,并利用该装置进行了功率MOS场效应晶体管的SEB、SEGR效应研究 ,给出了被测试器件SEB、SEGR效应的损伤阈值。结果表明 ,该测试系统和实验方法是可行、可靠的。     

MOSTET器件单粒子烧毁效应（SEB）截面测量

MOSFET功率管器件是卫星关键器件之一。单粒子烧毁(SEB)效应指由于功率晶体管中的高电流状态致使器件损伤,造成永久性破坏。在本MOSFET功率管烧毁效应截面测量实验装置的探测器室中,DUT为被研究的10片MOSFET功率管器件,连同检测探测器SD2和位置灵敏探测器PPSD一起,固定在可沿焦面移动的小车上。通过92芯真空密封座引出,器件与专用MOSFET功率管测试系     

抗辐射加固高压NMOS器件的单粒子烧毁效应研究

由于施加高栅极工作电压,使得器件容易发生重离子辐射损伤效应,其中,重大的重离子辐射损伤效应是单粒子栅穿效应（SEGR）和单粒子烧毁效应（SEB）。本文介绍了抗辐射加固高压SOI NMOS器件的单粒子烧毁效应。基于抗辐射加固版图和p型离子注入工艺,对高压器件进行抗辐射加固,提高器件的抗单粒子烧毁能力,并根据电路中器件的电特性规范,设计和选择关键器件参数。通过仿真和实验结果研究了单粒子烧毁效应。实验结果表明,抗辐射加固器件在单粒子辐照情况下,实现了24 V的高漏极工作电压,线性能量传输（LET）阈值为835 MeV·cm2/mg。     

典型VDMOSFET单粒子效应及电离总剂量效应研究

利用252Cf源和60Coγ射线源对典型VDMOSFET进行单粒子效应和电离总剂量效应模拟试验,给出典型VDMOSFET的单粒子烧毁(SEB)、单粒子栅穿(SEGR)效应测量结果以及不同偏置条件下漏源击穿电压随辐照剂量的变化情况。结果表明,VDMOSFET对SEB和SEGR效应以及VDMOSFET漏源击穿电压对电离总剂量效应比较敏感,空间应用时需重点考虑VDMOSFET的抗SEB和SEGR能力;考核VDMOSFET的抗电离总剂量效应能力时对阈值电压和击穿电压等敏感参数应重点关注。     

功率MOS器件单粒子烧毁效应的PSPICE模拟

建立了功率MOS器件单粒子烧毁效应的等效电路模型和相应的参数提取方法,对功率MOS器件的输出特性和单粒子烧毁效应的机理进行了分析和PSPICE模拟,模拟结果与文献中提供的数据相符合,表明所建立的器件模型和模拟方法是可靠的。     

功率MOS器件单粒子栅穿效应的PSPICE模拟

建立了功率ＭＯＳ器件单粒子栅穿效应的等效电路模型和相应的模型参数提取方法,对ＶＤＭＯＳ器件的单粒子栅穿效应的机理进行了模拟和分析,模拟结果与文献中的实验数据相符合,表明所建立的器件模型和模拟方法是可靠的。     

JFET区宽度对SiC MOSFET单粒子效应的影响

SiC MOSFET(金属-氧化物半导体场效应晶体管)关键参数——结型场效应晶体管(JFET)区宽度一直被认为是SiC MOSFET单粒子效应的主要影响因素。针对这一影响因素,以同一结构不同JFET区宽度的1.2 kV SiC MOSFET器件为对象进行单粒子效应实验,探究JFET区宽度对器件单粒子烧毁阈值电压、漏电退化阈值电压以及负栅压条件下器件性能的影响。结果表明：随着JFET区宽度的减小,漏电退化阈值电压增大;减小器件JFET区宽度可有效改善器件的抗单粒子效应能力;在负栅压条件下对器件单粒子效应也会有此效果。采用Sentaurus TCAD进行模拟仿真,模拟结果证实,JFET区宽度以及负栅压的变化会影响氧化层下JFET区内空穴的积累,随之影响氧化层电场强度,从而影响器件单粒子漏电退化,与实验结果相符。以上结果为SiC MOSFET抗单粒子效应加固提供了理论基础。     

典型光电子器件辐射效应数值分析与试验模拟方法研究

选取Si太阳电池与线阵CCD器件，进行了光电器件辐射效应的数值分析与模拟试验方法研究。分析了光电器件电离效应和位移损伤机理，利用二维器件模拟软件MEDICI，模拟了1MeV电子对n／p型硅太阳电池主要输出参数的影响，包括开路电压Voe、短路电流Isc和最大输出功率Pmax.在一定范围内，计算结果与文献实验数据符合较好。建立了线阵CCD器件辐照效应离线测量系统。利用^60Coγ源，进行了商用器件的总剂量效应试验，给出了暗电流信号和饱和电压信号的变化曲线。     

SOI器件瞬时剂量率效应的激光模拟技术研究

为验证激光模拟技术用于半导体SOI器件瞬时剂量率效应研究的可行性,对其优势和主要原理进行了分析。利用0.13 μm SOI MOS器件单管测试芯片进行了激光辐射实验,获得了不同尺寸器件辐射所激发的瞬时光电流与激光入射能量的关系曲线,并计算得到了线性拟合后的光电流表达式。通过激光实验数据与器件TCAD仿真结果的对比,获得了本文实验条件下的辐射剂量率 激光能量模拟等效关系。结果表明,激光模拟技术可用于半导体SOI器件瞬时剂量率效应研究。     

Cell design modifications to harden an N-channel power IGBT againstsingle event latchup

A device simulator is used to analyze the heavy ion induced failure mechanism in insulated gate bipolar transistors (IGBTs) and to investigate hardening solutions. Single event latchup was already identified as the failure mechanism. Lateral and vertical modifications of the P⁺ plug are proposed to reduce the efficiency of the parasitic thyristor, responsible for the latchup, and validated by 2D-simulations on a N-channel IGBT cell structure     

Medium-energy heavy-ion single-event-burnout imaging of powerMOSFETs

We present the first experimental determination of the SEB sensitive area in a power MOSFET irradiated with a high-LET heavy-ion microbeam. We used a spectroscopy technique to perform coincident measurements of the charge collected in both source and drain junctions together, with a nondestructive technique (current limitation). The resulting charge collection images are related to the physical structure of the individual cells. These experimental data reveal the complex 3-dimensional behavior of a real structure, which can not easily be simulated using available tools. As the drain voltage is increased, the onset of burnout is reached, characterized by a sudden change in the charge collection image. “Hot spots” are observed where the collected charge reaches its maximum value. Those spots, due to burnout triggering events, correspond to areas where the silicon is degraded through thermal effects along a single ion track. This direct observation of SEB sensitive areas as applications for, either device hardening, by modifying doping profiles or layout of the cells, or for code calibration and device simulation     

中子辐照诱导Si PIN光电二极管暗电流增大的数值模拟

分析了中子辐照诱导Si PIN光电二极管暗电流增大现象的机理,建立了Si PIN光电二极管的器件物理模型和中子辐照效应模型。运用MEDICI软件进行数值模拟计算,得出了1MeV中子在辐照注量为1010～1014cm-2时,Si PIN光电二极管暗电流变化的初步规律。数值模拟结果与相关文献给出的实验结果吻合较好。     

Development and application of a dual RELAP5-3D-based engineering simulator for ABWR

For any innovated plant design, the designed paper plant can be converted into a computer as a digital plant with advanced simulation techniques before being constructed into a real plant. A digital plant, namely engineering simulator, can be applied for: (1) verification of system design and system integration, (2) power test simulation, (3) plant transient and accident analyses, (4) plant abnormal and emergency procedure development and verification, (5) design change verification and analysis, etc. An advanced engineering simulator was successfully developed for the LungMen advanced boiling water reactor (ABWR) plant to support various applications before and after commercial operation. This plant specific engineering simulator was developed based on two separate RELAP5-3D modules synchronized on a commercial simulation platform, namely 3-Key Master. On this advanced LungMen plant simulation (ALPS) platform, major plant dynamics were simulated by two separate RELAP5-3D modules, one for reactor system modeling and the other for balance of plant (BOP) system modeling. Moreover, major control systems as well as emergency core cooling system (ECCS) were all simulated in great detail with built-in tasks of this commercial simulation platform. Different from real time calculation on training simulator, precision of engineering calculation is intentionally kept by synchronizing modules based on the most time-consuming one. During synchronization, each module will check its’ own converge criteria in each small time advancement. This plant specific advanced ABWR engineering simulator has been successfully applied on: (1) licensing blowdown analysis of feed water line break (FWLB) for containment design; (2) phenomena investigation of low-pressure ECC injection bypass during FWLB; (3) analysis of FW pump performance during power ascending; (4) verification of plant vendor's pre-test calculations of each start-up test.     

星用功率MOSFET器件单粒子烧毁试验研究

针对国产功率MOSFET器件JTMCS081和JTMCS062,利用实验室的MOSFET器件单粒子烧毁试验测试系统,在²⁵²Cf模拟系统上开展了单粒子烧毁评估试验研究。通过试验研究获得了被试器件单粒子烧毁的电压阈值,为被测器件在卫星型号的使用提供技术参考依据。     

Development of an automated system for fuel reload patterns design

In this paper an automated system to generate fuel reload patterns for a boiling water reactor (BWR), based on heuristic search methods using engineers expertise is presented. The main components of the system are the knowledge base, the inference engine, the 3D BWR simulator PRESTO-B and the user interface. The knowledge base includes a generation knowledge base and a modification knowledge base, which are concerned with the way human experts generate reload patterns. The system has been developed and applied to the Laguna Verde Nuclear Power Plant, achieving similar patterns to those used in the operation. No optimization algorithm has been incorporated in this system, therefore the generated reload patterns are the best estimate according the knowledge and experience of the nuclear engineers. Future works are being developed in this area using evolutionary optimization techniques as a complement of this system.     

Designing a linear silicon drift detector

The design and 2D simulation results of a Silicon Drift Chamber with a rectangular configuration are presented. The proposed structure is intended to allow a test of the technology used in the production of the device and serve as a basis to verify different solutions in the design of drift detectors     

贯穿件J形坡口焊接残余应力分析

核电站反应堆压力容器(RPV)顶盖控制棒驱动机构(CRDM)管座J形坡口焊缝在一回路高温高压水环境下存在应力腐蚀开裂(SCC)的风险,而焊接残余应力是SCC的主要驱动力。使用二维轴对称模型有限元方法对CRDM中心管座J形坡口进行焊接残余应力分析。为了探索一种简单、高效和保守的方法,研究了热源简化、焊缝形状简化、屈服强度、相变和强化行为对焊接残余应力的影响。结果表明:双椭球热源与均匀热源得到的残余应力结果基本一致;焊缝形状由鱼鳞状简化为方块模型对焊接残余应力结果影响不大,但是与合并焊道的结果相差较大;采用低屈服强度得到的残余应力结果并不保守;在ANSYS软件中,固液相变对残余应力结果影响不大;等向强化模型的结果比随动强化模型的结果保守;在工程上,建议采用均匀热源、方块焊道模型和等向强化模型进行焊接模拟。     

辐照硬化位错动力学模拟的研究进展

辐照硬化是金属材料的辐照效应之一,开展辐照硬化机理研究有助于设计可靠的反应堆结构材料。辐照产生的缺陷会对位错运动造成阻碍,被认为是辐照硬化的主要原因。近年来快速发展的位错动力学模拟方法为材料的微观组织变化和宏观力学性能之间建立起了桥梁,被广泛用于辐照硬化机理研究。对于一些辐照缺陷如位错环和层错四面体,位错动力学软件已能模拟它们对位错网络演化以及宏观力学响应的影响,使辐照硬化的定量预测成为可能。本文从位错动力学模型、不同类型辐照缺陷硬化效应的位错动力学模拟以及辐照硬化理论模型发展三个方面,综述了辐照硬化位错动力学模拟的研究进展,并展望该研究领域的主要科学问题。