A Novel MONOS Memory With High- HfLaON as Charge-Storage Layer

MIS capacitors with a high-κ HfLaON or HfLaO gate dielectric are fabricated by using a reactive sputtering method to investigate the applicability of the films as a novel charge-storage layer in a metal-oxide-nitride-oxide-silicon nonvolatile memory device. Experimental results indicate that the MIS capacitor with a HfLaON gate dielectric exhibits a large memory window, high program/erase speed, excellent endurance property, and reasonable retention. The involved mechanisms for these promising characteristics with HfLaON are thought to be in part from nitrogen incorporation leading to higher density of traps with deeper levels and, thus, higher trapping efficiency, stronger Hf-N and La-N bonds, and more stable atomic structure and HfLaON-SiO₂ interface, as compared to the HfLaO dielectric.