| Summary: | 碩士 === 中原大學 === 工業與系統工程研究所 === 105 === This thesis considers a unrelated parallel machines scheduling problem with several unavailability periods on each machine, where the machine has to be stopped in order to change the cleaning agent. The problem appears in the process in wafer manufacturing company. Each job leaves dirt i.e., particle, organic materials and metal-ions, on the surface of the wafer while processing. The dirt is moved by dissolving in a cleaning agent. Once the accumulation of dirt is over a permitted value, it is necessary to interrupt the processing and change the cleaning agent. The objective is to minimize the number of tardy jobs. The problem integrate production scheduling and cleaning activities and is strongly NP-hard. A mixed binary integer programming model is developed to find the optimal solution and a simulated annealing heuristic is proposed to find the near optimal solution. Computational results indicate that the performance of the heuristic is ….Furthermore, the efficiency of the mixed binary integer programming model and the impact of the dirt accumulation as well as cleaning time are explored in detail.
Keywords: Scheduling; Wafer cleaning; number of tardy jobs; BIP; Simulated Ennealing; unrelated parallel machines.
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