Collaborative Scheduling of Start-up Transient Process for Cluster Tools with Equipment Front-End Module

Wafer fabrication is a critical process in semiconductor manufacturing. Cluster tools with Equipment Front-End Module (EFEM) are widely used in wafer fabrication. These tools consist of a Vacuum Module (VM), LoadLock Module (LLM), and EFEM. The function of the LLM to switch between the atmospheric and vacuum environments increases the complexity of collaborative scheduling. The dynamic variation of the workload during the start-up transient process also makes the problem even more difficult. To address these issues, this study focuses on their collaborative scheduling mechanisms between robots and the LLM. A scheduling sequence is proposed to coordinate a single-arm robot in EFEM and a dual-arm robot in VM with the LLM. Based on this sequence, a Linear Programming Model (LPM) is developed to optimize the start-up transient process. Finally, experiments are conducted to verify the effectiveness of the proposed method.