Effect of nitrogen incorporation on 1/f noise performance of metal-oxide-semiconductor field effect transistors with HfSiON dielectric

Nitrided hafnium silicate is the leading candidate for possible replacement of SiON as a gate dielectric. 1/f noise characteristics of plasma and thermally nitrided Hf-based high-dielectric constant (high-k) gate dielectrics were investigated. Plasma nitrided samples showed less noise than thermally nitrided samples. The mobility fluctuation component of 1/f noise was found to show a strong process dependence, specifically on the nitridation technique. Increase in the number of Coulomb scattering sites due to the additional Si–N bonds near the high-k/Si interface is suggested as the reason for this dependence. This work represents the first investigation on the effect of different nitridation methodologies on low-frequency noise mechanisms in ultrathin (∼2 nm) Hf-based high-k nMOSFET (metal-oxide-semiconductor field effect transistor).