A novel process to form cobalt silicided p(+) poly-Si gates by BF2+ implantation into bilayered CoSi/a-Si films and subsequent anneal

Abstract

A novel process that implants BF2+ ions into thin bilayered CoSi/a-Si films has been shown to form cobalt silicided pf poly-Si gates with excellent gate oxide integrity and very small flatband shift. The effects of not only using the CoSi layer as an implantation barrier but also keeping the a-Si underlayer during the initial silicide formation both significantly suppress the boron penetration through thin gate oxide.