Sun Xiaojie, Wang Shuguang, Cai Qingyuan, Liu Jingze, Li Changhai, Hu Ertao, Li Jing, Wang Songyou, Zheng Yuxiang, Chen Liangyao, Lee Youngpak
State Key Laboratory of Photovoltaic Science and Technology, Department of Optical Science and Engineering, School of Information Science and Technology, Fudan University, Shanghai 200433, China.
Shanghai Key Laboratory of Optical Coatings and Spectral Modulation, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
Nanomaterials (Basel). 2025 Apr 24;15(9):645. doi: 10.3390/nano15090645.
Vanadium and oxygen form a complex system of vanadium oxides with multiple phases and mixed valency, increasing the difficulty of characterization. In this work, amorphous vanadium oxide thin films with mixed valence states were fabricated by atomic layer deposition, and then post-annealing was conducted for crystalline films. For the surface analysis of this mixed-valence system, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) were employed. However, XPS is only able to quasi-quantitatively determine the surface-proximity oxidation states. To account for the inadequacy of surface-sensitive XPS and AES techniques, a surface oxidation model (SOM) was proposed for the ellipsometric modeling of the mixed-valence system. Furthermore, by conducting air thermal oxidation (ATO) experiments, the four sets of fitting parameters of SOM were decreased to three, lowering the system complexity. This study is expected to help with the analysis of vanadium oxide mixed-valence systems and other multivalent metal oxide systems.
钒和氧形成了一个具有多相和混合价态的氧化钒复杂体系，增加了表征的难度。在这项工作中，通过原子层沉积制备了具有混合价态的非晶氧化钒薄膜，然后对结晶薄膜进行了退火处理。对于这个混合价态体系的表面分析，采用了X射线光电子能谱（XPS）和俄歇电子能谱（AES）。然而，XPS只能准定量地确定表面附近的氧化态。为了解决表面敏感的XPS和AES技术的不足，提出了一种表面氧化模型（SOM）用于混合价态体系的椭偏建模。此外，通过进行空气热氧化（ATO）实验，SOM的四组拟合参数减少到了三组，降低了系统的复杂性。这项研究有望有助于氧化钒混合价态体系和其他多价金属氧化物体系的分析。
