Sequencing Wafer Handler Moves to Improve the Performance of Hybrid Cluster Tools

Abstract

Cluster tools are highly integrated machines that can perform a sequence of semiconductor manufacturing processes. The sequence of wafer handler moves affects the total time needed to process a set of wafers.<p> Reducing this time can reduce cycle time, reduce tool utilization, and increase tool capacity. This paper introduces the cluster tool scheduling problem for hybrid cluster tools, which are multiple-stage tools that have at least one stage with two or more parallel chambers. <p>This paper presents algorithms that can find superior sequences of wafer handler moves. Experimental results show that the tool performance can be improved significantly if the wafer handler follows a cyclic sequence instead of using a dispatching rule.