Designing semiconductor cluster tool systems is a complicated task due to the nature of automatic operations and various configurations of modules and task response priorities of robots. System designers have to synchronize the wafer processing time of each module with robot operation times in order to obtain maximum throughput from the system. A simulation model was developed to reflect the process flows of wafers to and from wafer carriers through various modules in the cluster tool system. The model was first utilized to ascertain the best system configuration of the proposed systems, then utilized to design a cluster tool system that will meet the specific customer requirements. 1 PROJECT BACKGROUND A cluster tool manufacturer proposed new designs of two cluster tool systems, an independent deposition modules system and an integrated deposition modules system. The cluster tool systems consist of the following components: wafer carrier, Aligner, Dual Wafer Load Lock(DWLL), Degas St...