The initial oxidation behaviors of uranium nitride UNx (x = 0, 0.23, 0.68, 1.66) films

Abstract The initial oxidation behaviors of uranium nitride films with different N/U ratios have been focused in the present work. Uranium nitride films with different nitrogen content, UN x (x = 0, 0.23, 0.68, 1.66), have been prepared on the Si substrate by radio frequency magnetron sputtering method. The experimental results showed that the UN x (x = 0, 0.23, 0.68, 1.66) films were fine and dense. The initial oxidation processes of uranium nitride films were investigated in an ultra-high vacuum chamber of Auger electron spectroscopy. After 105 L oxygen exposure, the oxide layer of UO 2 were formed on the surface of U, and UN 0.23 , UN 0.68 films formed UO 2 with little UN x O y , while the UN 1.66 film generated UN x O y oxide layer. UN 1.66 film exhibited the thinnest oxide layer and provided the best considerable protection against oxygen attack. Also, the AES transition lines of UN x O y were identified for the first time.