Optimal Dispatching Policy and Simulation Studies for Multi-Product Multi-Tool Semiconductor Manufacturing Processes

• Main Authors: Chin-Feng Chen, 陳金鳳
• Other Authors: Chuei-Tin Chang
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/35119004324956175891

碩士 === 國立成功大學 === 化學工程學系碩博士班 === 97 === Semiconductor manufacturing is one of the most fast-growing industries in today’s world. As feature sizes shrink and wafer sizes increase, intricate control methods are needed to improve the product quality and tools utilization. In this thesis, the semiconductor manufacturing process is treated as multiple queuing systems operated in parallel and, also, it is assumed that the exponentially weighed moving average (EWMA) controller is implemented to adjust the process recipe of each system from run to run. Based on these assumptions, a mixed integer nonlinear programming model is formulated to determine the optimal dispatching policies for maximizing process capability or minimizing tool utilization rate. Systematic numerical simulation procedure is also devised to confirm the validity of the dispatching model. The simulation results show that the predictions of this model are reasonable. Moreover, the impacts of changing parameters values are investigated in extensive case studies and their optimal values are identified also. Finally, since accurate estimates of the model parameters may not always be available, the allowable range of tuning parameter is recommended to achieve an acceptable process capability.