Agent-based dynamic scheduling for semiconductor wafer fab

Semiconductor wafer fab is considered as the third kind of production system, differentiated with job shop and flow shop. It has its own scheduling and control characteristics, such as re-entrance, large-scale, mix processing model and unbalanced production facilities. To solve scheduling problem of semiconductor wafer fab, an agent-based scheduling approach for semiconductor wafer fab is proposed. Firstly, an agent-based scheduling model, which integrates release control, dispatching and machine maintenance scheduling, is presented. Secondly, negotiation protocol between agents, extended contract net protocol (ECNP), is given. Thirdly, scheduling algorithms for decision making of agents are offered. Finally, a simple model, but with essential characters of semiconductor wafer fabrication, is used to demonstrate how to use the proposed agent-based scheduling approach.