PROJECT TITLE :

Modeling, Analysis, and Scheduling of Cluster Tools With Two Independent Arms

ABSTRACT:

Twin-armed cluster tools for semiconductor manufacturing sometimes have had two arms fixed in opposite directions. Recently, new cluster tool robot systems with 2 independent robot arms are introduced with the expectation that the arms’ flexibility can improve the throughput. But, the productivity gain has nevertheless to be examined. Accordingly, we have a tendency to examine below which circumstances and the extent to which productivity gains can be achieved and how the robot task sequences ought to be scheduled to maximise the throughput. For this purpose, we have a tendency to develop a Petri web model that represents the tool behavior. We tend to show that the well-known swap sequence, that is thought to be optimal for typical dual-armed tools, isn't forever optimal. Instead, we establish two alternative sequences that are optimal under bound conditions. We have a tendency to define the workloads for every process step and therefore the transport module to derive conditions for optimality of the sequences, based on the Petri net model and therefore the workload. We tend to additionally develop a mixed integer programming (MIP) model to determine optimal sequences among one-cyclic schedules for the cases in which the proposed sequences are not optimal. Furthermore, we have a tendency to analyze and demonstrate how the 2 freelance arms will increase the throughput in comparison to a standard twin-armed robot.