Optimal Scheduling of Combined Wafer Fabrication Equipment Taking Mechanical Arms as Buffers

This paper addresses the problem of optimal scheduling of combined dual-arm wafer fabrication equipment which may take its two mechanical arms as temporary buffers during manufacturing process. Firstly, the mathematical model is proposed to describe the problem of the optimal scheduling of the mechanical arms and processing cavities of the combined dual-arm wafer fabrication equipment. The model takes minimizing the average processing time for each wafer as its objective. Then, a heuristic algorithm is designed to solve the problem. Finally, this paper employs some data cases which come from practical production of wafer to verify the validity of the algorithm and the method. The experimental results show that the efficiency of the combined wafer manufacturing equipment can be increased greatly through taking its two mechanical arms as temporary buffers.