OR Practice - Development and Implementation of a Scheduling System for a Wafer Fabrication Facility

This paper describes a scheduling system developed and implemented at a semiconductor company that manufactures specialty epitaxial wafers. We discuss implementation issues and describe the algorithms that form the basis of the scheduling system. We present computational results with representative data, and illustrate that scheduling procedures can be simplified considerably when they are preceded by a planning stage. The authors learned this fact through interaction with managers of the firm, and this changed the preconceived direction of the work in this application. The result is a formalization of the planning and scheduling problems.