Advanced WIP control for make-to-order wafer fabrication

This paper gives an overview of advanced scheduling and dispatching policies for WIP (work in process) management within the wafer fabrication process. Additionally, the pros and cons of general WIP control philosophies are opposed. Several control policies are evaluated for the application in complex make-to-order environment such as ASIC production. Based on the real shop floor environment of Philips SMST and the currently used control policies a proposal is presented answering the following two questions: what are the requirements of tomorrow's WIP control systems applied in make-to-order wafer fabrication; and how can these control policies be implemented and introduced on the shop floor using existing WIP control and scheduling systems?.