晶圆加工生产线蚁群优化排程方法

从实际应用的角度,分析了晶圆加工生产线排程特点,建立了晶圆加工生产线排程数学模型(LSM-WFL),给出了以瓶颈设备为核心、蚁群优化算法为主要工具的晶圆加工生产线排程方法(LSA-WFL)。基于实际生产线模型仿真验证的结果表明,LSA-WFL能够在允许的时间内获得晶圆加工生产线排程方案。     

半导体晶圆生产线调度的性能指标体系研究

针对半导体晶圆生产线调度，提出了由用于日生产计划的调度方案对比的短期性能指标，和用于每日投料计划的、实施分析的长期性能指标组成的半导体晶圆生产制造系统的性能指标体系．其中，短期性能指标分为与产品有关的在制品值、移动步数和移动速率，以及与设备有关的设备利用率、负载程度、排队队长和瓶颈率；长期性能指标主要包括产品的加工周期、流程参数和生产率．在此基础上，设计并实现了半导体晶圆生产线调度性能评价系统，以指导半导体车间的实际生产．该系统已经在工厂中得到应用．     

基于规则的批处理设备调度方法在半导体晶圆制造系统中应用

针对半导体炉管区瓶颈设备的批处理调度问题,提出满足工艺约束和设备限制的组批调度算法.在考虑产品动态到达的基础上,根据半导体制造系统大规模、多重入、混合型生产等特征,针对晶圆平均等待时间进行优化,实现多产品、多机台的实时组合派工.仿真实验在一个虚拟的晶圆制造系统上进行.结果表明,该算法在实时派工中对瓶颈设备填充率和利用率显著提升,有效地缩短了产品加工周期.
     

Preparation of FePt magnetic nanodot arrays by nanosphere lithography

Magnetic FePt nanodot arrays are promising candidates for making quantum magnetic recording disk. Here we introduce a hybrid method of FePt nanodot array fabrication through nanosphere lithography. This method combines the advantages of both top-down and bottom-up approaches and does not re- quire expensive equipment nor complicated processing steps.The size of magnetic FePt nanodots prepared can be as small as 40 nm.     

MEMS封装中的关键技术

简要分析了MEMS(微机电系统)器件封装的难点所在，随后介绍了晶片键合，晶片级密封，倒装芯片技术等主要的MEMS封装技术。     

半导体硅片加工过程复合控制策略研究及仿真

复合优先级控制策略CPC是一种兼顾投料与调度策略的生产过程综合控制策略。通过比较加工任务的复合优先级系数，CPC策略能够确定下一个加工任务，以及决定何时投放新工件。CPC策略甚至能够暂停非瓶颈设备以避免瓶颈设备前的在制品堆积。仿真结果表明，这种复合控制策略是一种能够同时优化多种性能指标的生产过程控制策略，可降低加工周期及其方差，减少生产过程中的在制品数，提高设备利用率及生产率等。     

基于ZPET-FF和ESO的直线伺服鲁棒跟踪控制

提出一种将零相位误差跟踪和前馈(ZPET-FF)与扩张状态观测器(ESO)相结合的重复控制方法,以提高宏动台直线电机伺服系统的跟踪性能.以ZPET-FF作为前馈跟踪控制器,将信号估计器估计的跟踪误差和系统的实时误差作为其输入信号,将控制器对系统的跟踪误差进行实时补偿,以降低参数变化对系统的影响,有效提高系统的带宽和跟踪性能,减小系统的动态跟踪误差;采用ESO补偿系统中的各种扰动抑制噪声,以提高系统的抗干扰能力.实验结果表明,所提出的控制方法不仅提高了系统的动态跟踪性能,而且减小了系统的跟踪误差.     

衬底硅片质量对SDB工艺的影响研究

硅-硅直接键合技术广泛应用于SOI、MEMS和电力电子器件工艺中,衬底抛光片的质量对键合质量及器件性能起着至关重要的影响。衬底抛光片的质量包含几何尺寸精度及表面状态质量,会影响键合过程中的界面应力,或造成键合界面空洞的产生,从而影响键合质量。     

On the origin of dissimilar pore evolution on patterned and unpatterned (100) n-type silicon

Via systematic investigation of the anodization of both patterned and unpatterned specimens, phenomena of pronounced discrepancy with respect to pore size, pore density and pore etch-rate were evidenced. Based on the detailed analysis of scanning electron microscope (SEM) micrographs and current-voltage curves, the competition between physical and chemical elements was found to be crucial to understanding the observations. The results indicate that the size, density and growth-speed of pores may act as an evident function of the initial morphology of the sample surface, despite a nearly fixed width of the space charge region. Electric-field effect as well as current-burst-model (CBM) was employed to interpret the underlying mechanism. Supported by the Hi-Tech Research and Development Program of China (Grant No. 2006AA04Z312) and National Basic Research Program of China (Grant No. 2006CB300403)     

Disc-Electrospun PCL Nanofiber Formed Micro-patterned Structure Scaffold

Disc-electrospinning using a disc as spinneret and a rotary drum as collector is a novel technology to prepare nanofiber which has been applied in tissue engineering scaffolds. In this study, nanofibrous mats with mlcro-patterned structure were fabricated via disc-electrospinning. Poly （ε-eaprolactone） （PCL） was dissolved in trifluoroethanol （TFE） at various concentrations （ 2 %-7 % ） （w/v） for electrospinning and the applied voltage ranged from 40 to 70 kV. Scanning electron microscopy （SEM） was employed to observe the morphology of the nanofibrous scaffolds. SEM images illustrated that the nanofibers with beads formed micro-patterned structure such as triangles and other polygons. The average diameter of nanofibers presented various size with the concentration increased from 2% to 7%. The beads on the nanofibers constructed the vertexes of the polygons, while nanofibers bridged between adjacent vertexes. The concentration of solution and applied voltage may be two dominant factors to influence the topological structure of the nanofibrons scaffolds. Cells cultured on the micro-patterned scaffold spread along the edges of the polygons. The scaffold with patterned structure may have a promising application in tissue engineering.