Low temperature UV/ozone oxidation formation of HfSiON gate dielectric

Abstract

Physical and electrical properties of hafnium silicon oxynitride (HfSi x O y N z ) dielectric films prepared by UV ozone oxidation of hafnium silicon nitride (HfSiN) followed by annealing to 450 °C are reported. Interfacial layer growth was minimized through room temperature deposition and subsequent ultraviolet/ozone oxidation. The capacitance–voltage ( C– V) and current–voltage ( I– V) characteristics of the as-deposited and annealed HfSi x O y N z are presented. These 4 nm thick films have a dielectric constant of ∼8–9 with 12 at.% Hf composition, with a leakage current density of 3×10 −5 A/cm 2 at V fb+1 V. The films have a breakdown field strength >10 MV/cm.