Capacity planning through queueing analysis and simulation-based statistical methods: A case study for semiconductor wafer fabs

This paper presents a comprehensive framework for the strategic capacity expansion of production equipment in semiconductor manufacturing, and the proposed approach is applied to a model of an actual wafer fabrication facility. It is the intention of this work to show that, once intelligently integrated, an analytical queueing model and a numeric computer simulation model can be used synergistically and can lead to a better alternative method than methods restricted to only one of them. The outcome of our methods is a number of good system configurations, each of which is characterised by its cycle time (CT)-throughput (TH) profile. Such profiles fully describe the system's comprehensive performance over a wide range of demand scenarios (involving varying product mix), and hence can be used to thoroughly evaluate alternative configurations in capacity expansion decisions.