An Adaptive Method for Flexible Configurations of Single-Arm Cluster Tools: Modeling and Scheduling.

Traditionally, process modules in cluster tools can execute a single operation only. With the rapid development of equipment design, recent cluster tools tend to have multi-functional process modules (MPMs) serving for processing multiple operations together in a single module. However, the different function settings of MPMs make the tool configuration various such that it is difficult to determine a schedule plan. Meanwhile, with different wafer processing parameters, a reasonable function setting for MPM can result in an excellent schedule so as to maximize the productivity. Thus, to solve the scheduling problem of a single-arm cluster tool with MPMs, a timed Petri net model is established to describe the behaviors of the system. Based on the model, two algorithms are developed to calculate the makespan for completing a given number of wafers. Then, an adaptive schedule method is presented to set the functions of MPMs to minimize the makespan. Finally, experimental results show the efficiency and effectiveness of the proposed method.