Liquid Injection MOCVD Grown Binary Oxides and Ternary Rare-Earth Oxide as Alternate Gate-Oxides for Logic Devices

摘要

High dielectric constant (high-k) materials having large band gap, good stability in contact with silicon and reasonable conduction/valance band offset with Si are needed to replace SiO_2/SiON in the future CMOS technology [1]. The oxides of Zr, Hf, and their silicates were considered as candidates for high-k gate-oxides initially. While not disclosed, the most probable dielectric used, in the present day dual core processors, is a form of nitrided hafnium silicate (HfSiON) or HfZrON, with the stoichiometry still not known to the public [2]. However, their maximum dielectric constant value is merely -14. Additionally to make the performance worst, they are susceptible to trap-related leakage currents which tend to increase with electrical stress for thinner films and that make it unsuitable as a future high-k dielectric for technology node ≤ 22 nm.