基于原位共角椭偏与反射谱的TiO2薄膜光学常数分析

为了分析溶胶-凝胶法制备的TiO₂薄膜的光学常数，采用旋涂法制备了多层TiO₂薄膜，利用扫描电镜对表面形貌进行了分析，利用椭圆偏振光谱对薄膜的折射率色散和孔隙率进行了拟合分析，并利用原位共角反射光谱对拟合结果进行了验证，得到了TiO₂薄膜厚度、孔隙率和折射率色散曲线。结果表明，TiO₂薄膜厚度与旋涂层数成线性关系，薄膜孔隙率约为15%且与旋涂层数无关，New Amorphous色散模型可以较好地拟合溶胶-凝胶旋涂方法制备的TiO₂薄膜在1.55eV~4.00eV波段的椭偏光谱。该研究为溶胶-凝胶法制备的TiO₂薄膜的光学常数测量提供了参考。

Analysis of optical constants of TiO2 thin film based on in-situ common angle ellipsometry and reflection

In order to analyze the optical constants of the TiO₂ thin film prepared by the sol-gel method,multi-layer TiO₂ thin films were prepared by spin-coating,and the surface morphology was analyzed by scanning electron microscopy.The refractive index dispersion and porosity of the film were analyzed by ellipsometry.The fitting analysis was carried out,and the fitting results were verified by in-situ common-angle reflectance spectroscopy.The TiO₂ thin film thickness,porosity,and refractive index dispersion curves were then obtained.The results show that the thickness of the TiO₂ thin film has a linear relationship with the number of spin coatings.The porosity of the film is about 15%and has nothing to do with the number of spin coatings.The New Amorphous dispersion model can fit the ellipsometric spectrum of TiO₂ thin film prepared by the sol-gel spin coating method in the 1.55eV~4.00eV band.This study provides a reference for the measurement of the optical constants of the TiO₂ thin film prepared by the sol-gel method.