Scheduling and Optimization Study of Semiconductor Manufacturing Systems with Residency Time Constraints and Wafer Cleaning

To ensure that the quality of wafers meets market demands, wafer manufacturers must strictly limit the residence time in slot-based wafer manufacturing systems with wafer cleaning operations, a common process in the semiconductor manufacturing field. However, when processing multiple types of wafers in slot-based wafer manufacturing systems, the constraints of wafer residence time and the scheduling of wafer cleaning operations make the scheduling problem more complex. To address this challenge, we first analyze the impact of residence time constraints and processing chamber cleaning operations on system scheduling when processing multiple types of wafers simultaneously. Based on a straightforward pull-based strategy, we developed a new scheduling method, with the key focus on determining the waiting time for the robot at each step. Based on this approach, we derived the feasibility conditions for wafer processing and developed a corresponding scheduling algorithm to implement cyclic scheduling. Finally, we provide examples to illustrate the feasibility and effectiveness of the developed method.