Semiconductor process line scheduling expert system

We report a newly developed semiconductor process scheduler using an expert system, which assigns the lots to be processed to each machine at each period. This system is developed using an expert system development-supporting tool ES/PROMOTE2/W-PLAN. In contrast to line simulators such as ManSim, our system aims mainly at detailed and optimized scheduling for the next few days. Our system was successfully applied to our prototyping line and resulted in an average 10% increase in scheduled process steps compared with the existing scheduler which mainly considers the FIFO condition.