A dispatcher simulator for a photolithography workshop

Photolithography is one of the most complex processes in semiconductor manufacturing. Lot scheduling within photolithography is a challenging activity where substantial improvement can be made. With the aim of determining effective dispatching strategies, Crolles 2 Alliance developed a dispatcher simulator tool which allows the study of dispatching strategies by simulation for the most common bottleneck workshop in the fab: the photolithography area. The originality of the present work lies in the fact the modeling tool is light meaning that the modeling is quite simple and the tool is flexible i.e. it would be easy to deploy to other workshops. In this article, using the simulator, we investigate dispatching strategies for regular lots and priority lots in the photolithography workshop and present some strategies that decrease the days at operation and that increase the number of daily moves.