Abstract
In general, the investment of manufacturing equipments in wafer fabs occupies most proportion of total investments. That is, the over-investing for equipments under a wafer fab where the releasing amount of wafer is fixed will not be helpful to raise the throughput. On the other hand, the lack of investment for equipments may result in the insufficient throughput, the loss of benefit and the terrible performance of manufacturing. In this thesis, we propose a productivity-oriented capacity optimization model to efficiently adjust the machine number in work-centers, raising the benefit of fabs and maintain the performance of manufacturing system to be in excellent status according to simulation and a fast search principal. The proposed method can be divided to four major modules, they are (a) the module of initial solution, obtaining the initial number of machines in all work-centers, (b) the module of validation, verifying the status of capacity for each initial solution, (c) the module of searching, evaluating the outstanding status of capacity in the manufacturing system, and (d) the module of adjusting, searching the better quality of solution for machine number in each work-center without violating the outstanding status of capacity. To verify the performance, a simulation model is constructed to evaluate the efficiency of out planning. The related results show that the proposed method can significantly reduce the number of simulations, raising the benefit of manufacturing system, and as well as a good tool for implementing in real world applications.