Behavior modeling and control of 300 mm fab intrabays using distributed agent oriented Petri net

In a 300 mm integrated circuit (IC) foundry fab, the intrabay automation is more important than a 200 mm one. In general, the intrabay automation systems include the automated controls of the process tools, overhead hoist transports (OHTs), stockers, and rail shortcuts. These control systems are operated concurrently. They must cooperate seamlessly to increase the system performance and to avoid deadlocks. In the paper, the behaviors of the intrabay automation systems are modeled using the distributed agent oriented Petri net (DAOPN). The fab intrabay DAOPN models are categorized into the new-order generation, OHT vehicle dispatching, zone control, path decision, and tool processing agent models. Finally, the DAOPN is defined, and the modeling procedures of the intrabay behaviors are all illustrated. Consequently, an experimental intrabay OHT loop is discussed and evaluated using the proposed DAOPN models and the DAOPN simulator.