SOLUTION APPROACHES FOR THE CLUSTER TOOL SCHEDULING PROBLEM IN SEMICONDUCTOR MANUFACTURING

With the increase in computer performance schedulin g complex manufacturing plants with global heuristics is becoming a realistic option. The complete factory scheduling problem consists of the global problem a nd its subproblems for each work center and machine. I semiconductor manufacturing a lot of processing is done using cluster tools. Cluster tools are a special ki nd of machine that can be described as a small factory. W e discuss solutions for the optimization of schedules for cluster tools which is a subproblem of the factory scheduling problem. Our main idea is to use rules b ased on slow-down factors or search approaches based on the use of slow-down factors for predicting the cycle t imes. We use simulation to evaluate the schedules.