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Robert C. Reuel, Intel, Rio Rancho, New Mexico, USA

ABSTRACT

The incorporation of lithographic APC solutions at Intel has shown how a simple concept such as active feedback control can be rife with obstacles and surprises. These encounters included automation and implementation challenges, myths, manufacturing learnings, and shifts in company policy. As the APC system began to mature and approach production proliferation, misconceptions and myths arose. Some engineers expected to see large capability improvements across all layers or to be able to associate end of line results to APC implementation. The fact that APC was implemented did not mean that process monitoring could be neglected or tool pairings could be disregarded. Processes could no longer be intentionally run off target. Metrology was found to be more important than ever, with the potential of having inaccurate measurements snowballing into multi-lot rework excursions. Furthermore, the roles of manufacturing technicians and engineers had to evolve, as manual process control was no longer required. Implementation of APC was a rare opportunity to profoundly change the landscape of semiconductor manufacturing within Intel. After negotiating many challenges, manufacturing was rewarded with a robust APC system, suitable for high volume manufacturing. Results to date for lithography have shown a 60% increase in capabilities and an associated 40% reduction in reworks.