Structural,optical properties and optical modelling of hydrothermal chemical growth derived Zn O nanowires

Zn O nanowire films were produced at 90°C using a hydrothermal chemical deposition method,and were characterised with scanning electron microscopy,optical transmission spectrometry and X-ray diffraction.The results showed that the optical band gap is 3.274-3.347 e V.Film porosity and microstructure can be controlled by adjusting the p H of the growth solution.Zn O nanowire films comprise a 2-layer structure as demonstrated by SEM analysis,showing different porosities for each layer.XRD analysis shows preferential growth in the(002)orientation.A comprehensive optical modelling method for nanostructured Zn O thin films was proposed,consisting of Bruggeman effective medium approximations,rough surface light scattering and O’Leary-Johnson-Lim models.Fitted optical transmission of nanostructured Zn O films agreed well with experimental data.

氢辅助脉冲直流溅射沉积的碳化硼薄膜的红外光学性质与机械性质的研究

采用氢气为辅助气体,在不同氢气流速下用微波等离子体辅助脉冲直流磁控溅射系统制备碳化硼薄膜。碳化硼薄膜的设计厚度为1200 nm,过渡层非晶硅的设计厚度为500 nm。所用的基板为载玻片、Ge、Si、Si wafer、GaAs和JGS3。之后,采用傅里叶红外光谱(FT-IR),X射线衍射(XRD)、维氏硬度计(Vicker indenter),分析了氢气流速(0、3、7和10 mL/min)对碳化硼薄膜的光学性质和机械性质的影响。结果表明,氢气流速的增加,可以明显提高红外光学透过率,降低红外光光吸收率。与此同时,氢气的增加还能降低薄膜应力,使薄膜易于附着在基底上。然而,氢气也会使得碳化硼薄膜硬度降低。