ULSI制造中硅片化学机械抛光的运动机理

从运动学角度出发,根据硅片与抛光垫的运动关系,通过分析磨粒在硅片表面的运动轨迹,揭示了抛光垫和硅片的转速和转向以及抛光头摆动参数对硅片表面材料去除率和非均匀性的影响.分析结果表明:硅片与抛光垫转速相等转向相同时可获得最佳的材料去除非均匀性及材料去除率.研究结果为设计CMP机床,选择CMP的运动参数和进一步理解CMP的材料去除机理提供了理论依据.     

化学机械抛光过程中扭矩的模型分析与试验研究

提出了一个计算化学机械抛光（Chemical Mechanical Polishing,CMP）过程中硅片所受扭矩的模型,并通过CMP过程中摩擦力和扭矩的在线检测试验进行了验证。试验结果表明该扭矩计算模型可以较好地描述CMP过程中硅片所受扭矩的特征。该研究可以为基于抛光头旋转轴扭矩变化的CMP终点检测方法提供理论依据。     

ULSI制造中硅片化学机械抛光的运动机理

从运动学角度出发，根据硅片与抛光垫的运动关系，通过分析磨粒在硅片表面的运动轨迹，揭示了抛光垫和硅片的转速和转向以及抛光头摆动参数对硅片表面材料去除率和非均匀性的影响．分析结果表明：硅片与抛光垫转速相等转向相同时可获得最佳的材料去除非均匀性及材料去除率．研究结果为设计CMP机床，选择CMP的运动参数和进一步理解CMP的材料去除机理提供了理论依据．     

化学机械抛光中的硅片夹持技术

目前半导体制造技术已经进入0.1 3μm时代,化学机械抛光(CMP)已经成为IC制造中不可缺少的技术.本文描述了下一代IC对大尺寸硅片(≥300mm)局部和全局平坦化精度的要求,介绍了目前工业发达国家在化学机械抛光加工中硅片夹持技术方面的研究现状,分析了当前硅片夹持技术中存在的问题,并指出了未来大尺寸硅片超精密平坦化加工中夹持与定位技术的发展趋势.     

超大规模集成电路制造中硅片化学机械抛光技术分析

目前半导体制造技术已经跨入0.13μm 和300mm时代,化学机械抛光(CMP)技术在ULSI制造中得到了快速发展,已经成为特征尺寸0.35μm以下IC制造不可缺少的技术。CMP是唯一能够实现硅片局部和全局平坦化的方法,但CMP的材料去除机理至今还没有完全理解、CMP系统过程变量和技术等方面的许多问题还没有完全弄清楚。本文着重介绍了化学机械抛光材料去除机理以及影响硅片表面材料去除率和抛光质量的因素。     

基于磨粒运动轨迹的硅片化学机械抛光材料去率研究

硅片化学机械抛光（CMP）是机械作用与化学作用相结合的技术,硅片表面的化学反应层主要是由抛光液中磨料的机械作用去除,磨粒对硅片表面的摩擦和划擦对硅片表面材料的去除起着重要作用。磨粒在硅片表面上的划痕长度直接影响硅片表面的材料去除率。本文首先在实验结果的基础上分析了硅片CMP过程中磨粒的分布形式,然后根据运动学和接触力学理论,分析了硅片、磨粒及抛光垫三者之间的运动关系,根据磨粒在硅片表面上的运动轨迹长度,得出了材料去除率与抛光速度之间的关系,该分析结果与实验结果一致,研究结果可为进一步理解硅片CMP的材料去除机理提供理论指导。     

移动式硅片退火设备的研制

对硅片退火设备的结构及功能进行了大量的改进,介绍了设备的工作原理、结构特点及达到的技术指标。研究了硅片在真空炉中的退火工艺。该设备的研究提升了硅片退火处理的稳定性及工艺性,达到了工艺要求的效果。     

名词释义——化学机械抛光（CMP）

CMP是利用抛光机、抛光液、抛光垫、抛光布在一定的工艺条件下实现材料表面高平坦化的一种技术。CMP技术来源于硅片抛光工艺 所用的设备和材料都与硅片抛光用的设备、材料等相似。利用这种技术可以使多层SiO2介质平面化和实现多层金属高密度互连，使多层电路结构能在一个近乎平坦的平面上进行制备，加速了低电阻率Cu取代Al作为互连线的步伐，降低了芯片的使用功耗。     

基于六维机械手的硅片传输系统

详细介绍了如何选择满足CMP抛光机硅片传输系统要求的六维机械手,并基于所选择的六维机械手配合换枪盘、末端执行器构建了硅片干进湿出式传输系统,最终利用示教盒示教出一条无碰撞、姿态合理的运动路径。     

化学机械抛光设备关键技术研究

化学机械抛光（CMP）技术作为目前唯一可提供在整个晶圆片上全面平坦化的工艺技术,已被越来越广泛地应用到了半导体领域。介绍了CMP技术原理、晶片夹持、抛光台温度控制、抛光垫修整、终点检测、抛光后清洗等技术以及未来对国内CMP设备的展望。     

Near-and Far-Field Thin-Wire Coupling?Theory and Expeiment

The method of moments is applied to near-and far-field coupling problems for thin-wire antennas with arbitrary orientation, excitation, and loading. A coupling matrix is derived. The analysis method is validated by the results of an extensive experimental program. Comparisons are made between theory and experiment for coupling from monopole to monopole, dipole to dipole, and dipole to dipole in the presence of parasitic elements. Special approximate formulas are developed for parallel thin-wire dipoles and monopoles. The moment methods permit accurate computation of antenna coupling in a wide variety of situations.     

AC space charge effects on beam loading of a cavity

A calculation of the loading of a resonant cavity by an electron beam is presented. This calculation is the first to include all effects of ac space-charge. The fields in the cavity are determined in the presence of the beam, including the effects of higher order structure modes. The formulation also explicitly includes Ramo's space-charge waves of all ranks. The result reduces to the conventional ballistic beam loading result for low beam current. Comparison of the complete theory developed here with the ballistic result demonstrates that the ballistic theory is sufficiently accurate, typically accounting for the quality factor to within 5%, and the resonant frequency to within 1%. In addition, the theory is shown to agree well with particle-in-cell simulations.     

Test methodology for durability estimation of surface mount interconnects under drop testing conditions

This paper presents a generic methodology to determine the durability of surface mount interconnects in electronic assemblies, under drop loading conditions. Damage accumulated in the interconnects due to repeated drops is quantified in terms of local Printed Wiring Assembly (PWA) response (flexural strain, strain rate, acceleration, number of flexural cycles), rather than the loading (total impact energy, orientation and number of drops). The advantage is that the results are more generic and can be extrapolated to different assemblies and different loading/orientation conditions. A damage estimation model, based on the observed failure mechanism and mode, is used to determine the durability of the surface mount interconnects under the applied loading history. The same model can be used to extrapolate the results to field conditions. A case study, using a simple specimen, is presented to demonstrate the proposed methodology. Failures are observed in the interfacial intermetallic layer of the component bond pad in the corner solder joint. The generality of the method is demonstrated by calibrating the model constants with in-plane drop tests and then successfully predicting the durability for an out-of-plane drop test. Thus, the approach and model constants are shown to be independent of impact orientation and boundary conditions.     

一种两级运放中消除右半平面零点的新结构

提出了一种新的两级运放结构,可以消除由密勒补偿电容引起的右半平面零点。该结构采用多路径零点取消(MZC)的理论,不同于传统的方式,该结构直接利用了第二级的负载管,来引入前馈通路取消右半平面零点,简化了电路,降低了功耗。     

Asymmetric Parallel-Coupled Lines for Notch Implementation in UWB Filters

In this letter, a novel microstrip parallel-coupled line structure with two asymmetric loading stubs is proposed for notched band implementation in ultra-wideband (UWB) bandpass filter (BPF). The rejection band is introduced by adding asymmetric loading stubs to the two outer arms of three parallel-coupled lines. The lengths and the widths of the stubs can control the bandwidth of the notched filter and can set the notched band at a desired frequency. This structure has been applied to a single-stage UWB BPF in order to produce a narrow notched band inside its passband. The design is successfully realized in theory and verified by full-wave electromagnetic simulation and the experiment.     

表面结构和生长方向对WO3纳米线电子结构影响的第一性原理研究

The effects of the surface and orientation of a WO₃ nanowire on the electronic structure are investigated by using first principles calculation based on density functional theory（DFT）.The surface of the WO3 nanowire was terminated by a bare or hydrogenated oxygen monolayer or bare WO₂ plane,and the[010]- and[001]-oriented nanowires with different sizes were introduced into the theoretical calculation to further study the dependence of electronic band structure on the wire size and orientation.The calculated results reveal that the surface structure, wire size and orientation have significant effects on the electronic band structure,bandgap,and density of states （DOS） of the WO₃ nanowire.The optimized WO₃ nanowire with different surface structures showed a markedly dissimilar band structure due to the different electronic states near the Fermi level,and the O-terminated[001] WO₃ nanowire with hydrogenation can exhibit a reasonable indirect bandgap of 2.340 eV due to the quantum confinement effect,which is 0.257 eV wider than bulk WO₃.Besides,the bandgap change is also related to the orientation-resulted surface reconstructed structure as well as wire size.     

一款具有双方环结构的有源电路模拟吸波材料

简单阐述电路模拟吸波材料的吸波原理,提出使用CST电磁仿真软件,通过电抗加载的方式对有源电路模拟吸波材料进行分析的方法。设计一款具有双方环结构的有源电路模拟吸波材料,并使用该方法对其进行分析。仿真结果表明这款吸波材料具有良好的双频吸波特性,通过改变两个方环的加载电阻(即改变PIN管的偏置电流),可改变吸波材料的吸波频率。     

纳米MgO晶体制备及其二次电子发射系数理论研究

为了研究MgO晶体和二次电子发射效率间的关系,分析了直接沉淀镁盐法生成Mg(OH)_2以及三段式温度煅烧Mg(OH)_2制备MgO晶体的过程,并使用扫描电镜和XRD对制成的MgO晶体进行了表征。在此基础上,采用第一性原理对MgO晶体的能带结构和态密度进行了计算,分析了晶体表面的结晶取向对MgO二次电子发射系数的影响。实验结果表明,本方法制备的MgO为立方晶体,且晶粒尺寸均匀分布在40.65nm附近,晶面取向为(200)、(111)、(220),并沿(200)取向择优生长。常见的(110)、(100)和(111)三种晶面取向中,表面(110)取向的MgO晶体禁带宽度最低,材料表面的二次电子发射系数相对较高。     

A Study on the Connotation,Measuring Dimensions and Influence Factors of Sense of Circle in Mobile Social Networks

The cultural psychology of Chinese differential pattern has produced the circle phenomenon, and the objective existence of the circle is also eroding all aspects of our life. Sense of circle is the subjective cognition of circle, guiding the expression and coordination of interpersonal relationships. With the rapid development of mobile social networks, the research of network circles has become a hot topic nowadays. This paper explores the structural connotation, measuring dimensions and influence factors of sense of circle by qualitative research and empirical test method. Results from this study shows that the connotation of sense of circle consists of four dimensions: shared beliefs, reciprocal exchange, role orientation, social structure and twelve component factors, Among them, shared beliefs consists of emotional attribution, common values, demand fulfillment. Reciprocal exchange consists of sense of resources, thinking orientation, interactive acquisition. Role orientation consists of responsible consciousness, learning consciousness, volunteering consciousness. Social structure consists of stratum categories, implicit norms, and tie strength. And these 4 dimensions has different significance level, especially the finding of role orientation improving and developing existing circle theory in social network. These conclusions make up the deficiency of the existing research, and have guiding influence on enterprises’ innovation and strategy.     

VxWorks环境下End型网络驱动软件开发

网络驱动软件在嵌入式开发中起着重要作用，特别是在通过网络进行下载调试阶段。结合在开发过程中所用到的End（Enhanced net work driver）型网络驱动，着重分析了Vxworks系统下的网络结构及其网络驱动软件的开发。分析了开发End型驱动时所用到的数据结构，网络结构中各层提供的接口以及包的存储结构和收发包的过程。通过这些分析，用户可以了解驱动的工作原理，便于开发。