Abstract The present study deals with the local structure of amorphous TiO2 and Fe-doped TiO2 thin films deposited on Si substrate using magnetron sputtering. The absence of long range order is confirmed by grazing incidence x-ray diffraction and the short range order is studied using x-ray absorption near edge structure (XANES) measurements at Ti, Fe and O K-edges and Fe and Ti L3-edge. The XANES provides understanding about the electronic transition induced from the short range ordering and dependence of electronic hybridization of the central Ti-p orbitals with the Ti-d orbitals. The XANES measurements also show that maximum Fe doping concentration allowed to replace Ti is 2 at.% and after that separate phase starts appearing, which is consistent with simulation by ab-initio multiple scattering theory based code FEFF9. Ellipsometry measurements show gradual decrease in band-gap energy upto 2 at.% Fe doping from pristine TiO2, however a drastic decrease in band-gap energy is observed at 4 at.% or higher doping concentration due to formation of other phases.

中文翻译：

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n 掺杂 Fe 的 TiO2 非晶薄膜的局部结构研究

摘要 本研究涉及使用磁控溅射沉积在 Si 衬底上的非晶 TiO2 和 Fe 掺杂 TiO2 薄膜的局部结构。通过掠入射 x 射线衍射证实不存在长程有序，并使用在 Ti、Fe 和 O K 边缘以及 Fe 和 Ti L3 边缘的 x 射线吸收近边结构 (XANES) 测量研究短程有序. XANES 提供了对由短程排序引起的电子跃迁以及中心 Ti-p 轨道与 Ti-d 轨道的电子杂化的依赖性的理解。XANES 测量还表明，允许替代 Ti 的最大 Fe 掺杂浓度为 2 at.%，在此之后开始出现单独的相，这与基于 ab-initio 多重散射理论的代码 FEFF9 的模拟一致。