功率MOSFET器件单粒子烧毁252Cf源模拟试验研究

本工作涉及利用²⁵²Cf源进行辐射效应试验研究的方法。结合功率MOSFET器件单粒子烧毁测试技术，对功率MOSFET器件辐射效应进行模拟试验研究。研究结果表明：在空间辐射环境下，功率MOSFET器件尽量使用在低电压范围内；在电路设计中附加必要的限流电阻是1种十分有效的抗单粒子烧毁措施。     

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     

SiC器件单粒子效应敏感性分析

新一代航天器需要使用耐高压、功率损耗低的第3代半导体SiC器件，为了给器件选用和抗辐射设计提供依据，以SiC MOSFET和SiC二极管为对象，进行单粒子效应敏感性分析。重离子试验发现，在较低电压下，重离子会在SiC器件内部产生永久损伤，引起漏电流增加，甚至单粒子烧毁。SiC MOSFET和SiC二极管试验结果类似。试验结果表明SiC器件抗单粒子能力弱，与器件类型关系不大，与SiC材料有关。为了满足空间应用需求，有必要进一步开展SiC器件辐射效应机理、试验方法和器件加固技术等研究。     

功率MOS、IGBT单粒子烧毁、栅穿效应模拟实验研究

建立了利用^252Gf裂片源,模拟空间重离子引起的单粒子烧毁、栅穿效应的实验方法和测试装置,开展了功率MOS器件、IGBT的单粒子烧毁、栅穿效应的模拟试验研究,给出了被试器件单粒子烧毁、栅穿效应的损伤阈值,以及随器件偏置的变化规律。     

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。     

SiC MOSFET单粒子效应研究现状

伴随核能与空间技术的快速发展,SiC MOSFET等高压大功率器件的应用不断增加,其因环境中的高能粒子辐射所引起的单粒子效应问题（如单粒子烧毁、单粒子栅击穿等）也逐渐凸显。为全面深入认识该问题,首先,论证了SiC MOSFET的优势特性,及其在辐射应用中面临的关键问题。然后,整理了目前国内外关于SiC MOSFET单粒子效应的模拟计算、辐照实验及相应研究成果,总结了在SiC MOSFET单粒子效应研究中的主要关注点,并分析了SiC MOSFET单粒子效应敏感性较高的原因。最后,基于目前SiC MOSFET单粒子效应研究中仍存在的问题,展望了未来可重点关注的研究方向。通过系统总结国内外SiC MOSFET单粒子效应研究进展,希望能为研究SiC MOSFET单粒子效应物理机制以及改进其抗单粒子效应加固技术提供有价值的参考。     

一种抗辐照功率MOSFET器件

报道了一种抗辐射功率MOSFET,通过与国外同类产品的锎源以及钴辐照试验对比,其抗总剂量水平和抗单粒子能力均已达到国际领先水平,并深入研究了单粒子烧毁、单粒子栅穿以及总剂量辐照的机理,提出了大功率MOSFET抗总剂量及单粒子辐射的加固方法。     

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。     

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。     

n沟VDMOSFET单粒子烧毁的二维数值模拟

应用半导体器件二维模拟软件Medici对功率MOSFET器件单粒子烧毁SEB(Single Event Burnout)效应开展了理论模拟研究。理论模拟与以往的实验结果比较吻合,证明采取的物理模型的正确性。得到了SEB灵敏度与载流子浓度、基区宽度和发射结掺杂浓度等参数的变化关系,提出了改善SEB的几种加固措施。该模型对于评估器件SEB效应提供了理论方法。     

Single event burnout sensitivity of embedded field effecttransistors

Observations of single event burnout (SEB) in embedded field effect transistors are reported. Both SEB and other single event effects are presented for several pulse width modulation and high frequency devices. The microscope has been employed to locate and to investigate the damaged areas. A model of the damage mechanism based on the results so obtained is described     

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。     

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     

PIXE spectrum analysis taking into account bremsstrahlung spectra

Continuous background appearing over the wide region of X-ray energy in the PIXE spectrum is very troublesome presence in the peak fitting. In the usual manner, the spectrum of continuous background is predicted as a function of polynomial and is subtracted from the X-ray spectrum. However, the parameters of the polynomial are determined with difficulty in the case that the continuous background exists under many peaks of characteristic X-rays. We calculated the production cross sections of continuous X-rays for several elements on the basis of the theories of quasi-free electron bremsstrahlung (QFEB), secondary electron bremsstrahlung (SEB) and atomic bremsstrahlung (AB), and obtained the continuous X-ray spectrum as a function of atomic number and X-ray energy. X-ray spectra of a standard sample and of a bovine liver sample were analyzed by a pattern analysis method assuming the reference spectra consisting of characteristic X-rays and continuous X-rays for each element. The results of analysis are quite satisfactory. By the present method, the PIXE spectra can be analyzed under little influence of the background subtraction, and it enables us a full auto-analysis of PIXE spectrum.     

Completed installations and the individual commissioning of the KSTAR MG system

Peak power of 200 MVA is required in order to achieve the goal within a long pulse scenario for the final operation of the Korean Superconducting Tokamak Advanced Research (KSTAR). The available grid power is only 100 MVA at the National Fusion Research Institute (NFRI) site. Motor generator (MG) was considered as a method of resolving such problems. The design of the KSTAR MG system was completed in July 2010 and individual devices were produced by relevant manufacturers. The installation of individual devices was completed in December 2012. Specifically, the stator and rotor were assembled at the site due to their large size and weight. The bearings, variable voltage variable frequency (VVVF) and excitation systems were transported and installed on site after being manufactured externally.The building used for MG installation was built in 2011. With the building designed for ease of installation, an overhead crane was designed to allow access to the loading bay.In this paper, we discuss the installation of the MG system and the construction of the building suitable for installation of individual devices. In addition, performance on the test results of individual devices is also discussed.     

A flexible and robust soft-error testing system for microelectronic devices and integrated circuits

Single event effects(SEEs) induced by radiations become a significant challenge to the reliability for modern electronic systems. To evaluate SEEs susceptibility for microelectronic devices and integrated circuits(ICs), an SEE testing system with flexibility and robustness was developed at Heavy Ion Research Facility in Lanzhou(HIRFL). The system is compatible with various types of microelectronic devices and ICs, and supports plenty of complex and high-speed test schemes and plans for the irradiated devices under test(DUTs). Thanks to the combination of meticulous circuit design and the hardened logic design, the system has additional performances to avoid an overheated situation and irradiations by stray radiations. The system has been tested and verified by experiments for irradiating devices at HIRFL.