Suppression of leakage current and moisture absorption of la ₂O₃ films with ultraviolet ozone post treatment

In this study, ultraviolet (UV) ozone post treatment is proposed as an effective method of suppressing gate leakage current associated with the moisture absorption of lanthanum oxide (La₂O₃) films. It is considered that suppression effects come from the healing of oxygen vacancies in the film by the UV ozone post treatment, since the oxygen ambient annealing also shows similar suppression effects. As compared with the oxygen ambient annealing, however, the UV ozone treatment does not enhance the interface layer thickness between the La₂O₃ and Si substrates, whereas the oxygen ambient annealing does. Therefore, the UV ozone post treatment is an effective method of suppressing the moisture absorption of La₂O ₃ films.