集成电路ESD介质击穿过程中击穿电荷物理模型研究

在集成电路绝缘氧化层静电放电(ESD)介质击穿物理模型的基础上,讨论并建立了击穿电荷的数学物理模型,给出了击穿电荷与氧化层表面累积电荷密度的关系式.     

IC器件在HBM ESD脉冲电压下的介质击穿实验研究

在IC器件氧化绝缘层介质击穿物理模型的基础上,讨论了人体带电放电模型(HBM ESD)中的波动电压加于氧化层上时的介质击穿.发现了氧化层上的俘获空穴密度临界值随薄膜厚度的变化十分敏感,当厚度由0.010μm减少至0.003μm时,俘获空穴密度临界值由0.100 C/cm2减少至0.002 C/cm2.相应地,IC器件抗ESD的性能也急剧下降.     

VDMOSFET终端场板的设计考虑

对最基本的场板结构,通过理论推导,深入讨论了场板下氧化层厚度与击穿电压、氧化层玷污所带正电荷电量之间的关系;又给出了场板长度值与击穿电压和P*区结深之间的关系,为VDMOSFET的结构设计和工艺实施提供了理论的依据。     

快速热氮化改善n—MOSFET氧化层的加速击穿

研究不同类型，不同沟道长的ｎ沟金属－氧化物－半导体场效应晶体管在不同栅电压下工作时栅氧化层的击穿特性。结果表明，ＭＯＳＦＥＴ栅氧化层的加速击穿起因于沟道大电流，而栅氧化层进行快速热氮化可极大地改善其栅氧化层的击穿特性。     

SOI双槽隔离结构的耐压特性

理论推导了绝缘体上硅(SOI)双槽隔离结构的耐压模型.该模型表明,在SOI双槽隔离结构中,因隔离氧化层压降的不均衡,高压侧隔离氧化层提前发生介质击穿,从而导致SOI双槽隔离结构的临界击穿电压小于理论值.增大沟槽纵横比和减小槽间距可以减弱隔离氧化层上压降的不均衡性,提高SOI双槽隔离结构的临界击穿电压.Sentaurus器件仿真软件的模拟结果和华润上华半导体有限公司0.5μm 200 V SOI工艺平台下的流片测试结果均证明,减小槽间距和增大沟槽纵横比是提高双槽隔离结构临界击穿电压的有效方法,同时也证明了该耐压模型的正确性.     

钛金属表面微弧氧化的电击穿行为

通过研究微弧氧化时电极表面的电压和击穿电压与时间、溶液浓度及施加电流密度的关系,考察了钛金属在不同电解质溶液中微弧氧化时电极的表面电击穿行为.结果表明:微弧氧化过程中电极电压随时间呈不规则的锯齿型变化;在两种电解质溶液中,溶液浓度越大,电压越低;陶瓷膜表面的击穿电压随着电解质溶液浓度的增加呈指数规律衰减;电解质溶液浓度一定时,击穿电压与微弧氧化时所施加的电流密度没有明显关系.     

微弧氧化机理及电击穿模型

为了研究微弧氧化的基本过程和机理,采用自行设计的气体介质电极击穿放电试验装置,测量了微弧氧化过程中阴极和阳极之间的距离与最低击穿电压的关系曲线,并建立了微弧氧化阳极气泡击穿理论模型和阳极等效电路.结果表明:最低击穿电压Vk值大小随阴、阳极之间距离增大而近似线性增加,微弧氧化膜层是在气泡位于陶瓷层的孔隙处时而生长;阳极气泡击穿理论模型能够合理地解释微弧氧化的基本过程和机理,并为改善微弧氧化工艺和提高膜层性能提供了理论基础.     

GaAs MMIC钝化层介质Si3N4的可靠性评价

在斜坡电压应力条件下对GaAsMMIC介质层Si3N4的击穿特性进行了测试,探讨了电容面积、周长以及斜率对与时间有关的介质击穿（TDDB）特性的影响．实验结果表明,电容面积越大,周长越长,介质中的缺陷就越多,其击穿电压也就越低,可靠性越差．根据TDDB线性电场模型,采用不同斜率的斜坡电压应力测试数据预测了正常工作电压下的Si3N4寿命．与温度加速实验相比,文中所提方法快速、成本低廉．     

电压对TiO2纳米管阵列形貌及光电性能的影响

文章以电化学阳极氧化法在氟化铵、甘油电解液中制备了TiO2纳米管阵列,利用扫描电子显微镜观察了不同电压条件下制备样品的形貌。根据I-t曲线、I-V曲线及SEM图像讨论了TiO2纳米管阵列的生长进程和形成过程,并研究了样品的光电性能。结果表明:电压从25V升至55V时,管径、管长分别从40、2 000nm增至100、3 200nm;电压0.2V时,初始氧化层形成;电压升至1.4V,氧化层被击穿;氧化层的形成与场致溶解的相互影响导致在电压2～4V附近电流的起伏;电压大于5V时纳米管开始形成;25V与45V电压下制备的样品具有较好的光吸收和光电性能。     

脉冲和直流应力下栅氧化膜击穿特性的差别

本文讨论了在直流电压应力和脉冲电压应力作用下栅氧化膜击穿寿命的差别，脉冲应力下栅氧化膜击穿寿命大于直流电压下的击穿。而且频率越高，两者的差别越大，差别起因于脉冲低电平期间栅氧化膜损伤的自行减少。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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