氮气流量对磁控溅射C掺杂TiO2薄膜光学性能的影响

Influence of Nitrogen Flow Rate on the Optical Properties of C-Doped TiO2 Thin Films Deposited by RF Magnetron Sputtering

摘要:

采用磁控溅射法制备了C掺杂TiO₂薄膜,并研究了氮气引入溅射过程对薄膜光学性能的影响。利用X射线衍射仪、拉曼光谱仪、X射线光电子能谱仪、分光光度计和原子力显微镜分析了不同氮气流量下薄膜的微结构、元素价态、透光性能和表面形貌。结果表明,沉积的薄膜主要是非晶结构,拉曼光谱中存在少量锐钛矿相,且随着氮气流量增大,锐钛矿特征峰强度减弱,意味着晶粒出现细化。当氮气流量增大为4cm³/min时,C掺杂TiO₂薄膜内氮元素含量为3.54%,其光学带隙从3.29eV变化至3.55eV,可见光区的光学透过率明显提高。可见改变氮气流量可实现对C掺杂TiO₂薄膜光学带隙和光吸收率的有效调控。

Abstract:

C-doped TiO₂ thin films were prepared by magnetron sputtering and the influence of nitrogen on the films during the sputtering process was studied. The microstructure, composition, optical properties and morphology of TiO₂ thin films prepared under different nitrogen flow rates were investigated by X-ray diffraction, Raman spectrometer, X-ray photoelectron spectroscopy, spectrophotometer and atomic force microscopy. The results showed that all the deposited films were mainly amorphous and some weak anatase phase was found in Raman spectra. Moreover, with the increase of nitrogen flow rate, the characteristic peak intensity of anatase decreased, which meant grain refinement. When the nitrogen flow rate was up to 4cm³/min, the Ncontent in the C-doped TiO₂ films was 3.54% with its optical band gap changing from 3.29 to 3.55eV. At the same time, the transmittance of C-doped TiO₂ films increased obviously. It can be concluded that nitrogen flow rate can control the optical band gap and optical absorption properties of the C-doped TiO₂ films effectively.