Scheduling and control of tandem cluster tools

Abstract

This paper explores scheduling and control strategies for tandem cluster tools. In particular, it focuses on address- ing congestion that occurs within these tools, with an aim to alleviate such congestion in equipment schedules. In our analysis, we first present a mathematical model based on Timed Event Graph(TEG), assuming a 1-cyclic schedule. This model provides insights into the system behavior and aids in identifying potential bottlenecks. For more universal K-cyclic schedules, we introduce an analysis method using a feedback arc. The feedback arc method helps minimize potential system blockings at the intermediate buffer, thereby reducing the wafer delay. The results of our analysis show that our proposed method can effectively reduce congestion compared to ex- isting scheduling methods. Moreover, we demonstrate that this methodology can be applied to various general sequences, highlighting its versatility and applicability across different types of tandem cluster tools. Through these novel approaches, we contribute towards optimizing scheduling and control strategies within the context of semiconductor manufacturing, ultimately aiming to increase operational efficiency and productivity