Scott J. Mason

A comparison study of the logic of four wafer fabrication simulators

Many semiconductor manufacturing companies use one of the following four simulators to aid in analyzing, planning, and operating their manufacturing facilities: Tyecin Systems ManSim/X, AutoSimulations AutoSched, Systems Modelings Wafer Fabrication Template, or Chance Industrial Solutions Delphi, which Wright, Williams, and Kelly now licenses as Factory Explorer. A benchmark study of the four packages was conducted, using actual factory data. The packages each produce different results between replications of the data, due to the datas stochastic nature. The differences which exist between the simulation packages studied in this paper, along with the modeling assumptions required to model the data, caused differences in the experimental output metrics of interest: product cycle time and tool utilization parameters. Some possible reasons are each simulation packages batching logic, setup avoidance rules, and rework occurrence estimators.