Optimal Scheduling for the Automated Material Handling System in a Semiconductor Wafer Fabrication Plant

• Main Authors: Te-Wei Chen, 陳德偉
• Other Authors: Chun-Wei Lin
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/23923170983844479046

碩士 === 國立雲林科技大學 === 工業工程與管理系 === 102 === Due to the complexity of process and a large number of stochastic handling requirements, the semiconductor wafer fabrication process is always delivered by the AMHS (Automated Material Handling System, AMHS). However, during the handling process, wait for each other situation will happen to the vehicles. Therefore, the performance of the machines’ capacities will be affected by the delivery efficiency of AMHS. In this study, a semiconductor wafer fabrication in Taiwan is taken as an example to construct a model of optimal scheduling for the automated material handling system of transportation planning methods, and letting the vehicles to avoid wait for each other situations beforehand, and walking through the shortest route to processing machines. Use the genetic algorithms (GA) to obtain the minimal total makespan time. Through utilizing the scenario analysis and simulation to compare the performance between unidirectional monorail track, bidirectional monorail track and hybrid track under different situations, the outcome shows that the bidirectional monorail track has the best performance. With the utilization of sensitivity analysis and the increase of vehicles’ number, it is found that the total makespan time of wafer fabrication descends, and the total handling time ascends. To increase the number of rail shortcut by the symmetrical and asymmetrical short-cutting methods, it is discovered that both of the methods in this study have found that the total makespan time of wafer fabrication descends, and the total handling time descends too. In this study shows that the automated material handling system have a good performance in different scenarios.