Advanced Process Monitoring and Control Methods for Poly Gate CD Targeting

Abstract

Accurate poly critical dimension (CD) control is necessary to run speed-sensitive parts in high volume production. A source-of-variation study indicated that poly CD variation accounted for over 50% of end-of-line variation in speed and power for a critical production part. A team was established to implement process control methodologies to reduce poly CD variation. The team took a module-based approach - linking outputs from the lithography, etch, and implant areas to form the tightest possible control for optimal product performance