Comparative study of high-k HfLaON and HfON as charge-storage layer of MONOS memory

Storage properties of high-κ HfLaON or HfON dielectric as charge-storage layer in MONOS non-volatile memory device are comparatively investigated by fabricating MIS capacitors using reactive sputtering method. Larger memory window, higher program/erase speed, and reasonable retention were observed for the HfLaON MIS capacitor than the HfON MIS capacitor. This is probably because La incorporation in HfON could induce more traps with deeper levels and thus higher trapping efficiency, and more stable atomic structure compared to the HfON dielectric.