An ultra-thin silicon nitride gate dielectric with oxygen-enriched interface (OI-SiN) for CMOS with EOT of 0.9 nm and beyond

We demonstrate a SiN gate dielectric with oxygen-enriched interface (OI-SiN). A process in which oxygen atoms are incorporated after forming SiN provides enhanced nitrogen concentration and oxygen-enriched interface simultaneously even in the region of EOT < 1.5 nm. Thus we developed an OI-SiN gate dielectric with EOT of 0.9 nm that brought about low gate leakage current, good interface properties and excellent resistance to boron penetration.