采用磁控溅射沉积方法在Si基底表面制备U2N3+xOy薄膜，采用X光电子能谱(XPS)分析技术观测CO气氛环境下 U2N3+xOy薄膜表面腐蚀行为，以期获得 U2N3+xOy薄膜在 CO 环境下的表面腐蚀机理。结果表明：超高真空条件下， CO在U2N3+xOy薄膜表面表现为氧化特性；CO在薄膜表面吸附解离生成的C以无定形碳形式聚集在薄膜表面，深度剖析过程中并未观察到C向U2N3+xOy薄膜内部扩散；而解离生成的氧在薄膜内扩散并发生氧化反应，生成高价氧化物或铀氮氧化物和氮。氧化反应生成的氮向薄膜内部扩散，并在次表面反应生成富氮中间产物。随着CO暴露反应进程的推进，富氮层逐渐向薄膜内部迁移，这是导致U4f谱卫星峰变化的主要原因。
U2N3+xOy films were deposited on Si substrate by magnetic sputtering deposition method. The behaviors of U2N3+xOy after exposure to CO atmosphere was analyzed by X-ray photoelectron spectroscopy (XPS) to explore its CO corrosion mechanism. Under ultra-high vacuum (UHV) condition, it is found that CO atmosphere is oxidative on the surface of U2N3+xOy film. The dissociated carbon in forms of amorphous is segregated on the outmost surface rather than diffuses inside, and the diffusion of the dissociated oxygen resulted in oxidation of U2N3+xOy, leading to the formation of uranium oxy-nitrides in higher valence state on the surface and an N-rich layer as an intermediacy in the subsurface. The diffusion of oxygen in the film is suppressed on the very surface by the product of uranium oxides or ura-nium oxy-nitrides in higher valence state due to the potential barrier. The distance of the N-rich layer to the outmost surface dominates the intensity variation of satellites at 386.7 eV and 397.5 eV, which is enlarged with the oxidation process. All abore chemical changes play a very important role for understanding the corrosion mechanism of U2N3+xOy films.
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