Colored timed Petri-Net and GA based approach to modeling and scheduling for wafer probe center

In this paper, we propose an architecture to simulate Wafer Probe. We use a modeling tool named CTPN (Colored-Timed Petri Nets) to model all testing flow. With CTPN model, we can predict the delivery date of any specific product under some scheduling policies efficiently and precisely. In the scheduling phase, we combine two popular methods to construct high-quality schedules. One is to select machines for lots and the other 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. This CTPN-based GA scheduler and selection method enlarges the solution space and helps us to find the good solution so as to meet the requirements in the complicated environment.