Colored Timed Petri-Net and GA Based Approach to Modeling and Scheduling for Wafer Probe Center

• Main Authors: Shun-Yu Lin, 林訓宇
• Other Authors: Li-Chen Fu
• Format: Others
• Language: en_US
• Published: 2002
• Online Access: http://ndltd.ncl.edu.tw/handle/50771428426856641500

碩士 === 國立臺灣大學 === 資訊工程學研究所 === 90 === In this thesis, we propose an architecture to simulate Wafer Probe. We use a modeling tool named CTPN (Colored-Timed Petri nets) to model all testing flow. The main models include detailed machine behavior, capability, and routing. With these CTPN models, we can simulate the product delivery date efficiently and rather precisely. In addition, we can predict any product under some scheduling policies based on the proposed CTPN model. We achieve this goal by changing the priority of each lot in time. Since most of the scheduling rules (dispatching rules) are priority based ones, changing the priority of each lot can reflect the behavior of these rules. In the scheduling phase, we combine two popular methods constructing schedules. One is to select machines for lots and another is to select lots for machines. In each method, we use the GA based approach to search for the optimal combination of a number of heuristic rules. Our approach can be considered as taking the advantage of obtaining the fittest lot selection when the machine is idle, and acquiring the fittest machine selection when the lot finishes in each stage. This approach can increase the solution space and help us to find the good solution. In addition, the CTPN based GA scheduler takes less computation time than a lot of other schedulers, so that this GA scheduler can meet the need for a rapidly changing environmen