Reliability studies of Hf-doped and NH3-nitrided gate dielectric for advanced CMOS application

A novel technique is proposed for forming high-K dielectric of HfSiON by sequentially doping base oxide with Hf and nitridation with NH₃. The HfSiON gate dielectric demonstrates excellent device performances such as only 10% degradation of saturation drain current and almost 45 times of magnitude reduction in gate leakage compared to conventional SiO₂ gate dielectric at the same equivalent oxide thickness (EOT). Additionally, negligible flatband voltage shift is achieved with this technique. Excellent performances in electrical stressing are also demonstrated by the dielectric.