【作者】 廖飞红；

【导师】 李小平； 邵新宇；

【作者基本信息】 华中科技大学 ， 机械电子工程， 2012， 博士

【摘要】 基板运动台是平板显示扫描光刻机最关键的分系统之一,其精度和稳定性直接影响光刻机的产率、Overlay和成像质量。与IC前道光刻机的硅片台相比,基板运动台具有运动行程更大、扫描速度更快、负载更大、电机驱动反力更大的特点,这些因素都给基板台的减振和运动控制带来了巨大的挑战。本论文面向平板显示光刻机的性能需求,从基板运动台的主动减振、微动台局部减振两个方面展开研究,通过优化主动减振参数提高全局主动减振性能,设计重力补偿减振器结构和控制器以提高局部减振性能。采用理论推导的方法建立了主动减振系统的结构动力学模型,提出了减振器的结构参数的优化方法和主动减振系统PID参数快速整定方法。推导了摆机构的结构刚度模型和峰值应力模型,并以减振系统的水平向固有频率为设计目标,建立了以材料应力和结构尺寸为约束的非线性优化模型,应用序列二次规划方法计算出最优的摆机构结构参数,实验结果表明实际结构频率与理论值差异在10%以内；提出了采用3个步骤快速整定减振系统PID控制参数的方法,并进行了仿真和实验验证。局部减振系统采用了重力补偿减振技术,分别建立了局部减振系统单元级和系统级两个结构层次的动力学模型。理论分析了两种重力补偿减振器的刚度模型,选取了气囊型重力补偿减振器方案,并对气囊型结构的刚度模型进行了实验验证。推导了局部减振系统六自由度动力学模型,采用模态解耦法分析的刚体模态频率与实际值差异小于10%。提出了一种基板运动台垂向的运动控制方法,在电机位置控制环路中增加了气动力反馈环路,消除了负载重力变化造成的静态电机驱动力,从而降低直线电机的发热。试验结果表明,在不影响垂向控制精度的条件下,95%的负载重力被重力补偿减振器压力环路所补偿。基板运动台垂向精度高,且其三个自由度运动耦合,为此,本文推导了垂向微动台的GS/GB解耦矩阵,实现Z、Rx和Ry三轴运动控制的解耦。机电联合仿真结果显示,垂向运动台的结构和控制方案能满足精度指标要求。搭建了基板运动台水平向运动测试平台及垂向运动测试平台,对基板运动台的减振性能进行了测试。基板运动台水平向采用主动减振系统,X向超调量降低了近95%,Y向的超调量降低了65%,并且X/Y方向的伺服位置误差能在150ms内收敛到150nm范围以内。垂向测试平台测试结果表明Z、Rx、Ry和Rz四个轴的稳定时间在100ms以内,实现运动精度分别为97nm、140nrad、334nrad、268nrad,能满足设计指标需求。验证了本文所研究的基板台减振结构和方法的有效性。更多还原

【Abstract】 Plate stage is one of the key subsystems in Thin-film Transistor-Liquid Crystal Display (TFT-LCD) lithography equipment. Precision and stability of the plate stage affect the throughput, overlay and imaging performance of the tool Compared with wafer stage in Integrated Circuit (IC) lithography tool, the moving range, motion speed and the reation force of the plate stage are larger, and the vibration isolation and motion control are much more difficult. In order to fulfill the performance requirements of plate stage, global active vibration control and local area vibration isolation are studied in this dissertation. Both structure and control parameters of the active vibration isolators are optimized to improve the performance of global active vibration isolation system (AVIS). Also, structure and controller of the gravity compensation isolators are designed for local vibration isolation.The dynamic model of the AVIS is deduced with theoretical derivation. The optimization method for the structure parmaters and the self-tuning method for the PID controller are also proposed. The stiffness model and the peak stress model of the pendulum are presented. In order to minimize the margin of the horizontal natural frequency between the actual values and the design value, its optimal structure parameters are obtained by using the sequential quadratic programming (SQP) algorithm with the constraints of the material stress and geometry sizes. The experiment results show that the relative error of natural frequency between the experiment value and the design value is less than10%. And a self-tuning method with3steps is proposed to tune the PID parameters of the controller, which is approved both by simulation and experiment.Gravity Compensation and vibration Isolator are used in the Local Vibration Isolation System (LVIS), and the dynamic models of LVIS including unit level and system level are established.The stiffness models of two types of GCI are deduced and the corrugated diaphragm type is chosen for LVIS. The stiffness model of corrugated diaphragm type GCI is verified by an experiment. The6-DOFs dynamic model of the LVIS is deduced, and their model natural frequencies are calculated with model decoupling method. The experiment result shows that the relative errors of the model natural frequencies between the experiment values and the calculated values are less than10%.A motion control method for the vertical directions of the plate stage is proposed. Three pneumatic force feedback loops are added to the positioning control loops in vertical directions, in order to eliminate the static force of the motors and reduce the heat generated by the motors when the gravity force of the payload is varied. Experiment results show that the vertical positioning performance isn’t affected by the pneumatic loop, and95%of the static force of the Lorenz motor is compensated by the pneumatic loop.The vertical stage requires high precision positioning performance in Z/Rx/Ry/Rz directions, and the structure shows that strong motion couplings exit in Z/Rx/Ry directions. So the gain scheduling maxtrix and the gain balancing matrix are deduced for decoupling control of the vertical stage. The electro-mechanical simulation results show that the structure and the decoupling control method for the vertical stage fulfill the positioning its performance requirement.更多还原