High performance and highly stable ultra-thin oxynitride for CMOS applications

The device characteristics and manufacturability of ultra-thin oxynitride have been systemically studied in this paper for CMOS applications. We have found that the transistor with plasma oxynitride gate dielectrics gives better pFET performance in terms of drive current, mobility, threshold voltage and leakage current as compared to the one with thermal oxynitride. For nFET, the performance for transistors with plasma oxynitride and thermal oxynitride are almost equivalent. The manufacturability of plasma oxynitride is also thoroughly investigated. This paper proposes pre-conditioning process in plasma nitridation process which can significantly reduce the wafer-to-wafer variation for nitrogen and oxygen dose in the ultra-thin gate dielectrics.