P.A. Kraus, C.S. Olsen, K. Ahmed, T.C. Chua, R. Zhao, F. Nouri, & J. Cushing, Front End Products Group, Applied Materials, Inc., Santa Clara, CA, USA
ABSTRACT
Many technical and manufacturing challenges exist for scaling gate oxide dielectrics to 65 nm. Plasma nitridation of the gate oxide has demonstrated advantages in nitrogen dose and profile control over other nitridation methods. Improvements in the plasmanitridation process have been developed that result in improved device performance, including reduced threshold voltage shifts, reduced mobility degradation, and improved reliability. Clustering the gate oxidation, nitridation, post nitridation anneal, and poly deposition has also been demonstrated to reduce EOT, improve within wafer EOT uniformity, and enhance drive current over non-clustered processing. These improvements lead to scaling the plasma nitridation process to the 65-nm technology node.