Nitrided $\hbox{La}_{2}\hbox{O}_{3}$ as Charge-Trapping Layer for Nonvolatile Memory Applications

Charge-trapping characteristics of La
₂
O
₃
with and without nitrogen incorporation were investigated based on Al/Al
₂
O
₃
/La
₂
O
₃
/SiO
₂
/Si (MONOS) capacitors. The physical properties of the high-
k
films were analyzed by X-ray diffraction and X-ray photoelectron spectroscopy. Compared with the MONOS capacitor with La
₂
O
₃
as charge-trapping layer, the one with nitrided La
₂
O
₃
showed a larger memory window (4.9 V at ±10-V sweeping voltage), higher program speed (4.9 V at 1-ms +14 V), and smaller charge loss (27% after 10 years), due to the nitrided La
₂
O
₃
film exhibiting less crystallized structure and high trap density induced by nitrogen incorporation, and suppressed leakage by nitrogen passivation.