Managing manufacturing improvement using computer integrated manufacturing methods

The authors present the application of manufacturing improvement programs which use computer-integrated methods to track performance and gather data necessary for problem identification. This application focuses on existing wafer fabrication at Harris Semiconductor in Palm Bay, Florida. The authors specifically concentrate on the methodology used to improve key fabrication performance indices, such as throughput yield, cycle time, and performance to schedule. It is shown how CIM (computer-integrated manufacturing) methodology was critical to the improvement process. The specific methodologies discussed are the following: work-in-process management, inventory reduction, activity planning and work scheduling; equipment tracking, preventative-maintenance scheduling, and equipment performance; SPC (statistical process control) implementation and support, data collection, chart limit calculation, capability studies, and online support; and scrap reduction programs. A wafer inventory reduction of over 70% was realized and a product performance to mix of over 50% was realized during a 30 month period. Wafer throughput yield improved by over 30% during the 30 month period