An integrated approach to planning and scheduling at Philips Semiconductors

One of the most difficult environments for planning and scheduling is semiconductor fabrication. Some of these challenges include: high occurrence of breakdowns and scraps, highly fluctuating demands, interplant dependency, long lead-times with large numbers of iterative and complex processes, a diverse and rapidly evolving demand mix, and multiple production sites, geographic dispersion of fabrication and assembly/test, and outsourcing. These attributes of semiconductor fabrication create a highly dynamic environment under intense economic and technological pressure, compounded by global distribution of the manufacturing process. To successfully handle dynamism and the "networked" semiconductor enterprise requires a dynamic even "real-time", advanced planning and scheduling (APS) system that is tightly, integrated with all parts of the enterprise supply chain, from order entry, to material purchasing, through shop-floor lot sequencing.