精密晶圓檢測平台的高度穩定軌跡與速度控制

Abstract

近年來，隨著技術的進步，晶圓的尺寸逐漸增長，對晶圓檢測平台的運動控制性能提出了挑戰。晶圓檢測平台為一個精密而複雜的運動系統，本論文以提高精密氣浮運動平台的定位精度為目標，透過電腦模擬、迭代出可行的控制器參數後，以實驗驗證其運動性能。主要研究內容包含如下： 首先，推導了永磁同步線性馬達的數學模型，並以此為基礎，系統識別出運動平台各軸受控體的傳遞函數。 其次，為了降低系統識別的不確定性與外部干擾對平台運動過程中的影響，本論文採用由Tsai所提出的鏈散射描述法來設計常數增益值的H_∞控制器，並進一步引入粒子群最佳化演算法來簡化H_∞控制器設計過程中調整權重的流程。 最後，將經由多次迭代最終產生之控制器參數實驗於運動平台，驗證其成果，並討論了多種常用於評價運動平台的性能指標。

In recent years, with the advancement of technology, the size of wafer has been increasing, posing challenge to the performance of motion control of wafer inspection stage. Wafer inspection stage is a delicate and sophisticated motion system, and with the aim to improve positioning precision of air-bearing motion stage, this thesis obtains feasible controller parameters by computer simulations and iterations. The result of the computed controller parameters is verified by experiments. The main research achievements are the following: First, the mathematical model of permanent synchronous linear motor is deduced. Based upon the result, the transfer functions of all the plants of each axis are identified. Second, to lessen the effects of external disturbances and uncertainties on the motion stage, which arise inevitably during system identification, this thesis adopts the method of Chain Scattering Description proposed by Tsai to design H_∞ controller of constant gains. Moreover, the algorithm of Particle Swarm Optimization is introduced to simplify the process of adjusting weightings when H_∞ controller is being designed. Finally, the controller parameters computed from multiple iterations are experimented on the motion stage to verify their efficacy. Several performance indicators that are often utilized to evaluate motion stage are also discussed.