【作者】 李应辉；

【导师】 刘永智；

【作者基本信息】 电子科技大学 ， 光电工程， 2010， 博士

【摘要】 随着航天技术、核能技术及其核武器等高新技术的发展需求,越来越多的光电子器件需要正常工作于辐照环境中。辐照在器件中引入大量的氧化层电荷、界面态电荷及体内位错等缺陷,导致电参数退化,从而引起器件暂时失效或永久性失效。因此为保障器件在辐照环境中能正常工作,必须研究器件的辐照损伤机理,研究不同辐照环境中器件的损伤程度并对器件的抗辐照能力进行预先评估及诊断。目前,器件抗辐照评估方法是辐射退火筛选,这种方法周期长,经费高,不可能做大量样品的破坏性辐照实验,更重要的是它不仅不能保证所有的被辐照的器件经过退火后都能够恢复其初始性能,还有可能在被测器件中引入新的潜在缺陷,使器件的可靠性降低。这迫切要求一种简单、快速且完全非破坏性的辐射筛选和抗辐射能力评估技术。光电耦合器以其体积小、寿命长、无触点、抗干扰性强等优点广泛地应用于航空航天及核技术等领域,因此急需研究光电耦合器在辐照环境中的失效机理及抗辐照评估方法。辐照在光电耦合器件内部引入缺陷,而噪声与器件的内部缺陷密切相关。所以,借助光电耦合器的噪声理论来研究光电耦合器的辐照损伤理论是可行的。本文系统地研究了晶体管输出型光电耦合器的辐照效应,损伤机理及其评估方法。针对晶体管输出型光电耦合器的结构组成,详细阐述了其噪声理论、辐照机理和辐照效应,建立了光电耦合器的辐照噪声测试系统。详细介绍了光电耦合器的电离总剂量辐照特性和中子注量辐照特性,选用60COγ源进行总剂量电离辐照,首次建立了总剂量辐照下的光电耦合器的电流传输比模型和噪声模型,在反应堆上进行中子注量辐照,研究了光电耦合器的中子辐照电效应和噪声效应,并分析了该中子辐照噪声的分形特性,这为光电耦合器的辐照研究提供了研究思路和数据积累,提出了辐照噪声表征参量,填补了国内外在此领域的空白。结合以上理论,半导体器件原理及光电耦合器的可靠性噪声评估方法,研究了光电耦合器抗辐照能力的噪声评估方法,得到了一些重要研究结果,这些研究结果为更深入地开展半导体器件辐照评估方法奠定了实验和理论基础。更多还原

【Abstract】 As the rapid developments of advanced technologies of space technology, nuclear technology and nuclear weapons, an increasing number of optoelectronic devices are required to operate properly in irradiation environment. Irradiation introduces defects of oxide charges, interface state charges and internal displacements into the devices, causing a degradation of the electrical parameters and resulting in the devices with a semi-permanent or permanent ineffectiveness. Therefore, to ensure the devices work well in the radiation environment, it is necessary to make researches and diagnosis on their irradiation damage mechanism, damage degree and anti-radiation ability.Radiation-anneal techniques for devices of radiation environment are presently used.The more important thing is that this method will induce some new latent defects in the devices under test,let alone this method is expensive,time-waste and destructive.Under such conditions, a simple, quick and completely non-destructive technology for Radiation-anneal and anti-radiation evaluation is urgently required.Optocouplers with advantages of small size, long life, non-contact, and strong anti-interference are widely used in aviation and aerospace fields. So,it’s urgent need to research the invalidation mechanism and the anti-radiation evaluation method of optocouplers in radiation environment.Defects are introduced in optocouplers by radiation and the defects are extraordinary correlation with noise.So,It’s feasible to study the radiation damage of optocouplers in virtue of noise theory of optocouplers.In this paper, the systematic study of the irradiation effects, damage mechanism and evaluation method of optocouplers with transistor output is presented. For the composition of the optocouplers with transistor output, the noise theory, radiation mechanism and radiation effect are expounded, establishing an irradiation noise test system. And described in detail is the irradiation properties of both the total ionizing dose and neutron fluence. By choosing 60COγas the radiation sources to make the total ionizing dose, established a current transfer ratio model and noise model for optocouplers under the irradiation of total dose for the first time. The neutron fluence irradiation is carried out on reactor to study electric and noise effects of optocouplers, and an analysis of the fractal characteristics of the neutron irradiation noise is given, which provides research ideas and data for the irradiation study of optocouplers. A method of using irradiation noise to characterize the related parameters is proposed, which fills in this field at home and abroad.Combining with the above theory, working principles of semiconductor devices and the noise evaluation method for the reliability of optocouplers, noise assessment methods for evaluating the anti-radiation capacity are researched, obtaining important research results which establish the experimental and theoretical basis for the further development of irradiation evaluation methods for semiconductor devices.更多还原