热原子层沉积技术制备的TiAlC薄膜的性能

Properties of TiAlC Film Prepared by Thermal Atom Layer Depositing Technique

为了解以热原子层沉积技术制备的TiAlC薄膜的特性,在不同基底温度下,以硅和二氧化硅为基底材料制备了TiAlC薄膜;采用椭偏仪、分光光度计、X射线光电子能谱、原子力显微镜、X射线衍射仪对薄膜的性能进行了测试。结果表明:随着基底温度的升高,TiAlC薄膜平均透射率逐渐降低,吸收边产生红移,光学带隙由2.56eV降低到0.61 eV;薄膜的沉积速率由0.09 nm/cycle升高到0.20 nm/cycle,表面粗糙度由1.82 nm降低到0.49 nm;不同基底温度下生长的薄膜均为无定型结构;膜层中的氧源于空气的自然氧化,且膜层的氧化程度与膜层中TiC的含量及膜层的致密性有关;TiAlC薄膜的形成主要源于高温条件下TiC的形成及三甲基铝的分解。

TiA1C films were deposited on Si substrate and SiO2 substrate at various different temperature. Subsequently, the properties of TiA1C films were tested by ellipsometer, speetrophotometer, XPS, AFM and XRD. Results showed that with the increase of substrate temperature, the average transmittance of TiA1C films decreased gradually, and the absorption edge redshifted, as well as the optical band gap value decreased from 2.56 eV to 0.61 eV. The deposition rate of TiA1C films increased from 0.09 nm/cycle to 0.20 nm/cyele, and the roughness decreased from 1.82 nm to 0.49 nm. All of fihns prepared at various substrate temperatm＇e belonged to amorphous structure. Moreover, the oxygen element in the film came from the atmosphere, and the amount of oxygen in the film depended on the film density and the amount of TiC in the film. Be- sides, the formation of TiA1C films was contributed to the decomposition of trimethyl aluminium and the formation of TiC.