分光椭偏技术在铟锡氧薄膜光电特性研究中的应用

Application of Spectroscopic Ellipsometry for the Study of Electrical and Optical Properties of Indium Tin Oxide Thin Films

通过分光椭偏测量技术、并采用Drude和Tauc-Lorentz复合模型,研究了铟锡氧(ITO)薄膜在不同基底温度和退火过程中光学介电函数的变化。通过与霍尔效应以及光学带隙测试的数据对比,发现ITO薄膜的载流子浓度和光学带隙变化分别对材料红外和紫外波段光学介电函数有影响。通过分别研究材料在低能端和高能端的介电函数,得到光学介电函数与薄膜的载流子浓度和光学带隙的关系。该研究确定了利用非接触分光椭偏技术对ITO薄膜的电学和光学特性进行定量分析的近似方法。

The dielectric function transformation of ITO thin films caused by different substrates and post annealing temperatures is studied by spectroscopic ellipsometry measurement using Drude and Tauc-Lorentz combined modes. By comparing with the Hall effect measurement results and optical bandgap values calculated from transmittance and reflectance spectra, it is found that the influences on the dielectric functions from the carrier concentration and optical bandgap values occur at infrared and ultraviolet wavelength regions, respectively. The relationship between the dielectric functions and carrier concentration and optical bandgap is deducted by studying the dielectric functions at low and high energy regions. This study provides a new technological way to analysis the electrical and optical properties of ITO thin films by non-contact spectroscopic ellipsometry measurements.