Cycle time reduction at cluster tool in semiconductor wafer fabrication

Cluster tools have gained a lot of importance in today´s semiconductor manufacturing. Cluster tools are machines that combine several processing steps in one machine. A cluster tools basically consists of one or more loadlocks where wafers enter and exit the cluster tool, two or more processing chambers where the processes are performed, and one or more handlers which transport the wafers between loadlocks and processing chambers. They can be regarded as small factories inside a factory. This paper focuses on understanding the behavior of cluster tool system by simulation modeling, experimenting on the model and finding out the factors that influence the tool overall cycle time. The number of deposition chambers, number of robot grippers, clean cycle, MTTF and MTTR are identified as the most important factors for cycle time reduction at cluster tool in semiconductor wafer fabrication.