电离辐射对MFIS型铁电场效应晶体管电学性能的影响
发布时间：2018-08-07 07:26
【摘要】：铁电场效应晶体管(Fe FET)作为铁电存储器中的一员,在现代电子工业有广阔的应用前景,尤其是在国防电子工业中很受重视,其具有高存储密度、非挥发性、结构简单、强抗辐射能力等优点。金属层(Metal)-铁电层(Ferroelectric)-绝缘层(Insulator)-硅基底(Silicon)型铁电场效应晶体管(MFIS-FET)更是解决了金属层(Metal)-铁电层(Ferroelectric)-硅基底(Silicon)型铁电场效应晶体管(MFS-FET)铁电层与硅基底产生反应使器件性能降低的缺点。尽管铁电薄膜和铁电电容有很强的抗辐射性能,但是MFIS-FET是否具有很强的抗辐射能力,我们还不得而知。因为电子器件的微型化,所以每个单元层互相影响是在所难免的。器件的一部分具有很强的抗辐射能力,不代表整体具有很强的抗辐射能力,这就是我们平时所熟知的“木桶原理”。到目前为止,对Fe FET的抗辐射性能还没有清晰的研究结果。本文以MFIS-FET为研究对象,用理论模拟的方法对其进行定量的电离辐射效应模拟研究。首先,模拟研究了电离辐射环境下铁电层极化变化对其性能的影响;其次,模拟研究了电离辐射环境下硅基底电荷密度变化对其性能的影响;最后,模拟研究了电离辐射环境下铁电层电荷输运对其性能的影响。具体研究结果如下:(1)改进米勒模型使其适用于处于电离辐射环境中的铁电材料极化的模拟,将此模型代入MFIS-FET中进行计算。模拟结果表明,当铁电层受到10Mrad的辐射时,各物理量的变化很小,基本与辐射前相同;当辐射总剂量为100Mrad时,电容、源漏电流等衡量器件性能的物理量发生明显的改变,这说明器件随时有可能失效。(2)推导出了电离辐射环境下硅基底表面电荷表达式,代入器件模拟中进行计算,发现随着辐射剂量率的增大,器件的反型层电荷密度、电荷迁移率变化很小,源漏电流更是变化微小,但硅表面势有明显的变化。这说明了电离辐射作用在硅基底上对器件的性能影响不大。(3)建立了一个电离辐射环境下铁电层电荷输运的模型,计算结果表明,当电荷输运比例一定时,MFIS-FET电容曲线和源漏电流曲线随辐射总剂量的增大向负电压方向平移,且源漏电流增大。若源漏电流继续增大,器件有可能被烧毁。当辐射总剂量一定,MFIS-FET电容曲线和源漏电流曲线随绝缘层阻隔率的变化在一定范围内波动。电离辐射环境中,绝缘层的存在有利于调控器件的性能。
[Abstract]:Ferroelectric field effect transistor (Fe FET), as a member of ferroelectric memory, has a wide application prospect in modern electronic industry, especially in national defense electronics industry. It has high storage density, non-volatile and simple structure. Strong radiation resistance and other advantages. Metal layer (Metal) ferroelectric layer (Ferroelectric) insulator (Insulator) Si substrate (Silicon) type ferroelectric field effect transistor (MFIS-FET) solves the disadvantage that the ferroelectric layer of the metal layer (Metal) ferroelectric layer (Ferroelectric) silicon substrate (Silicon) type ferroelectric field effect transistor (MFS-FET) reacts with the silicon substrate to reduce the device performance. Although ferroelectric thin films and ferroelectric capacitors have strong radiation resistance, it is not known whether MFIS-FET has strong radiation resistance. Because of the miniaturization of electronic devices, it is inevitable that each cell layer interacts with each other. Part of the device has strong radiation resistance, does not mean that the whole has a strong radiation resistance, which is known as the "barrel principle". Up to now, no clear results have been obtained on the radiation resistance of Fe FET. In this paper, the quantitative ionizing radiation effects of MFIS-FET are simulated by theoretical simulation. Firstly, the influence of ferroelectric layer polarization on its performance is simulated. Secondly, the influence of silicon substrate charge density under ionizing radiation on its performance is simulated. The effect of ferroelectric layer charge transport on the performance of ionizing radiation was studied. The results are as follows: (1) the modified Hans Muller model is applied to simulate the polarization of ferroelectric materials in ionizing radiation environment, and the model is added to the MFIS-FET to calculate the polarization of ferroelectric materials. The simulation results show that, when the ferroelectric layer is radiated by 10Mrad, the variation of each physical quantity is very small, which is basically the same as that before radiation, and when the total radiation dose is 100Mrad, the physical quantities which measure the performance of the device, such as capacitance, source and drain current, are obviously changed. This indicates that the device may fail at any time. (2) the surface charge expression of silicon substrate in ionizing radiation environment is derived and calculated in the device simulation. It is found that with the increase of radiation dose rate, the inverse layer charge density of the device is obtained. The change of charge mobility is very small, the source and drain current is even smaller, but the surface potential of silicon has obvious change. This shows that ionizing radiation has little effect on the performance of the device on silicon substrate. (3) A model of charge transport in ferroelectric layer under ionizing radiation environment is established, and the calculation results show that, When the charge transport ratio is constant, the capacitance curve and the source-drain current curve of MFIS-FET are shifted to negative voltage with the increase of total radiation dose, and the source-drain current increases. If the source and drain current continues to increase, the device may be destroyed. When the total dose of radiation is constant, the capacitance curve and source / drain current curve of MFIS-FET fluctuate with the insulation barrier rate in a certain range. In the environment of ionizing radiation, the existence of insulation layer is beneficial to the performance of the device.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN386
本文编号：2169298
[Abstract]:Ferroelectric field effect transistor (Fe FET), as a member of ferroelectric memory, has a wide application prospect in modern electronic industry, especially in national defense electronics industry. It has high storage density, non-volatile and simple structure. Strong radiation resistance and other advantages. Metal layer (Metal) ferroelectric layer (Ferroelectric) insulator (Insulator) Si substrate (Silicon) type ferroelectric field effect transistor (MFIS-FET) solves the disadvantage that the ferroelectric layer of the metal layer (Metal) ferroelectric layer (Ferroelectric) silicon substrate (Silicon) type ferroelectric field effect transistor (MFS-FET) reacts with the silicon substrate to reduce the device performance. Although ferroelectric thin films and ferroelectric capacitors have strong radiation resistance, it is not known whether MFIS-FET has strong radiation resistance. Because of the miniaturization of electronic devices, it is inevitable that each cell layer interacts with each other. Part of the device has strong radiation resistance, does not mean that the whole has a strong radiation resistance, which is known as the "barrel principle". Up to now, no clear results have been obtained on the radiation resistance of Fe FET. In this paper, the quantitative ionizing radiation effects of MFIS-FET are simulated by theoretical simulation. Firstly, the influence of ferroelectric layer polarization on its performance is simulated. Secondly, the influence of silicon substrate charge density under ionizing radiation on its performance is simulated. The effect of ferroelectric layer charge transport on the performance of ionizing radiation was studied. The results are as follows: (1) the modified Hans Muller model is applied to simulate the polarization of ferroelectric materials in ionizing radiation environment, and the model is added to the MFIS-FET to calculate the polarization of ferroelectric materials. The simulation results show that, when the ferroelectric layer is radiated by 10Mrad, the variation of each physical quantity is very small, which is basically the same as that before radiation, and when the total radiation dose is 100Mrad, the physical quantities which measure the performance of the device, such as capacitance, source and drain current, are obviously changed. This indicates that the device may fail at any time. (2) the surface charge expression of silicon substrate in ionizing radiation environment is derived and calculated in the device simulation. It is found that with the increase of radiation dose rate, the inverse layer charge density of the device is obtained. The change of charge mobility is very small, the source and drain current is even smaller, but the surface potential of silicon has obvious change. This shows that ionizing radiation has little effect on the performance of the device on silicon substrate. (3) A model of charge transport in ferroelectric layer under ionizing radiation environment is established, and the calculation results show that, When the charge transport ratio is constant, the capacitance curve and the source-drain current curve of MFIS-FET are shifted to negative voltage with the increase of total radiation dose, and the source-drain current increases. If the source and drain current continues to increase, the device may be destroyed. When the total dose of radiation is constant, the capacitance curve and source / drain current curve of MFIS-FET fluctuate with the insulation barrier rate in a certain range. In the environment of ionizing radiation, the existence of insulation layer is beneficial to the performance of the device.
【学位授予单位】：湘潭大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN386
【参考文献】
相关期刊论文 前1条
1 苗彬彬;王君;陈江涛;闫鹏勋;;铁电PLZT薄膜的最新研究进展[J];人工晶体学报;2006年03期
，本文编号：2169298
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