金刚石薄膜电容的欧姆接触

用本征金刚石薄膜制备的电容具有高储能，高击穿电压，耐高温，基本电阻可调节以及良好的化学稳定性等特点.金属与金刚石薄膜形成欧姆接触是电极金属的选取是制备金刚石薄膜电容的重要一步.本文主要研究金刚石薄膜的欧姆接触及其I-V曲线.     

金刚石薄膜电容的欧姆接触

用本征金刚石薄膜制备的电容具高储能，高击穿电压、耐高温，基本电阻可调节以及良好的化学稳定性等特点。金属与金刚石薄膜形成欧姆接触是电极金属的选取是制备金刚石薄膜电容的重要一步。本文主要研究金刚石薄膜的欧姆接触及其I-V曲线。     

金属—半导体欧姆接触合金化过程中小岛对比接触电阻影响的理论分析

1、引言在半导体发光器件中,Gap 发光器件占的比例越来越大,而 Gap 欧姆接触是当前 Gap 发光二极管(LED)制作中引人注目的问题.Gap 是宽禁带化合物,电阻率较高,表面态密度大,因而给欧姆接触电极的制备造成了很大困难.迄今,人们进行了各种合金作为 Gap 欧姆接触材料的研究工作,结果表明,对不同的接触金属层,在最佳合金温度下可得到较小的比接触电阻.随着Ⅲ—Ⅴ族半导体材料及其检测技术的发展,人们发现欧姆接触的实际界面     

p—GaP／Au—Sb／Au—Zn体系的接触界面

采用X光电子能谱(XPS)研究了Au-Zn/Au-Sb与p-GaP接触体系的界面结构及其组分随着A_r~ 溅射刻蚀深度的变化,实验结果表明,在一定的合金温度下由于GaP和Au-Zn/Au-Sb层之间金属-半导体互扩散生成Au-Ga反应层,GaSb化合物并含有Zn的原子,Zn内扩散使界面形成一个较高掺杂浓度的再生长层,可改善M-S欧姆接触性质,此外,界面上还有碳、氧杂质的沾污,有效地清除半导体表面氧化层对于制好欧姆电极是重要的。     

硅衬底高光效GaN基蓝色发光二极管

经过近十年的探索,作者在国际上率先突破了硅衬底高光效Ga N基蓝光LED材料生长技术及其薄膜型芯片制造技术,制备了内量子效率和取光效率均高达80%的单面出光垂直结构Ga N基蓝光LED,并实现了产业化和商品化,成功地应用于路灯、球炮灯、矿灯、筒灯、手电和显示显像等领域.本文就相关关键技术进行全面系统地介绍.发明了选区生长、无掩模微侧向外延等技术,仅用100 nm厚的单一高温Al N作缓冲层,制备了无裂纹、厚度大于3μm的器件级Ga N基LED薄膜材料,位错密度为5×108 cm-2.发明了自成体系的适合硅衬底Ga N基薄膜型LED芯片制造的工艺技术,包括高反射率低接触电阻p型欧姆接触电极、高稳定性低接触电阻n型欧姆接触电极、表面粗化、互补电极、Ga N薄膜应力释放等技术,获得了高光效、高可靠性的硅基LED,蓝光LED(450 nm)在350 m A(35 A/cm2)下,光输出功率达657 m W,外量子效率为68.1%.     

多晶硅接触薄发射极欧姆接触电极的研究

提出了制备新型多晶硅接触薄发射极晶闸管薄发射极欧姆电极的新结构－Ａｌ／Ｔｉ／Ｐｏｌｙｓｉ．结构。通过实验研究和对Ａｌ－Ｔｉ－Ｓｉ系统反应动力学的分析，解决了此结构的关键问题－Ｔｉ层厚度的确定方法及其制备工艺条件；对此结构的有效性和质量，即浅结的完整性以及欧姆接触电阻的大小进行了实验检查。采用此结构，已成功地制备出低损耗、快速薄发射极晶闸管管芯样品。     

基于气浮喷射的MEMS封装中通孔的金属互联

在微机电系统(MEMS)圆片级封装中,通孔缺陷极有可能降低芯片与外界电互联的可靠性.采用气浮沉积的方法,在通孔底部沉积纳米银浆,形成低电阻的Ag/Al/Si欧姆接触结构,解决了电极间的电学连接问题.根据AJTM300气溶胶喷射系统的特点,选择50nm粒径的纳米银浆制作通孔Ag/Al/Si欧姆接触结构;在平面圆形Al电极上气浮沉积纳米银浆,改变银浆的烧结温度,用以验证Ag对Al/Si接触电阻的影响;将此法应用于通孔互联结构中,并探究得出最优沉积时间,测量两通孔间的I-V特性.试验结果表明,采用超声雾化方式的气浮沉积方法,在通孔底部沉积15s的纳米银浆,经过300℃的烧结,可以有效填充通孔底部缺陷,并形成较低电阻的Ag/Al/Si接触结构.采用按需喷印的气浮沉积方案对通孔进行沉积,为实现MEMS芯片与外界的电互联提供了新思路.     

GaAs光导开关电极制备工艺及性能测试

为了解决目前GaAs光导开关成品率低、稳定性差和可靠性低等问题,提出了GaAs光导开关的关键电极制备工艺解决方案。该方案首先以半绝缘GaAs材料作为衬底,利用电子束蒸镀机在GaAs衬底上沉积Ni/Ge/Au/Ni/Au金属复合层作为光导开关电极,并对电极进行快速退火使其与GaAs衬底形成欧姆接触;然后,为了隔绝光导开关与外界环境,在GaAs衬底上沉积氮化硅作为钝化保护层;最后,通过在欧姆接触电极上外延场板的工艺,制备出电极间距为4 mm的异面GaAs光导开关。对所制备的GaAs光导开关的测试结果表明：在400℃退火条件下,电极的接触电阻率最低可达到0.019 5Ω·cm²;采用50Ω单脉冲形成线,在工作频率为1 kHz、偏置电压为22 kV时,光导开关的输出电压脉冲为10 kV,脉冲上升时间为亚ns量级。采用该制备方法制备的GaAs光导开关的成品率高达约98%,可稳定工作上万次。     

面向生物分子检测的MoS_2膜流体场效应管的制备

为提高生物分子检测的灵敏度,通过氮化硅基底的制备、二硫化钼(MoS_2)薄膜的铺陈以及金属电极的制备等步骤研制了MoS_2流体场效应管.将制备好的场效应管进行电学表征并分别在空气和浸润环境中进行性能测试.实验结果表明:当背栅电压为0 V时,漏极电流与电压呈线性关系,电极与二硫化钼样品之间的接触为欧姆接触;用机械剥离方法制备出的MoS_2薄膜为单层;浸润环境下场效应管上二硫化钼的电阻比空气中的小,这是由于浸润环境下样品杂质掺杂浓度提高所致;随着液栅电压的增加,漏极电流与电压的曲线斜率也会随之增加,场效应增强.作为一种新型的二维材料,二硫化钼可以用来制备流体场效应管和提高生物分子检测的灵敏度.     

高阻半导体薄层电阻测定方法研究

本文提出了高阻半导体薄层电阻的一种测量方法。将待测样品用平面技术制备成矩形,薄层电阻由所加直流电压和电流指示算出。测量精度取决于欧姆接触的保证及电表精度,由薄膜厚度的精确控制和测量,可精确测定薄膜电阻率。     

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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