Effects of plasma immersion ion nitridation on dielectric properties of HfO_2

摘要

Plasma immersion ion nitridation is used to produce thin HfO_2 films with improved thermal and electrical properties. The film composition is investigated by examining the chemical shifts of the Hf 4f, Si 2p, and N 1s core-level spectra using x-ray photoelectron spectroscopy. The improved thermal stability and interfacial microstructure are further confirmed by high-resolution cross-sectional transmission electron microscopy. Electrical studies show an equivalent oxide thickness of about 1.25 nm, a negligible hysteresis of about 5 mV, and a low fixed charge density.