椭偏光谱与椭圆旋向

Spectroscopic Ellipsometry and the Sense of Elliptical Polarization

椭圆偏振光谱因其独特的优点广泛应用于薄膜科学和技术中。光度法椭圆偏振光谱中椭圆旋向是不能直接确定的，从而不能确定椭偏参数Δ。这一定程度上有碍椭圆偏振光谱的应用。本文引入克拉末－克朗尼格（Ｋｒａｍｅｒｓ－Ｋｒｏｎｉｇ）关系，推导出椭偏参数的Ψ－Δ关系，从频谱的信息得出椭圆旋向。并比较了其应用的结果，表明由此可实现实验数据从［ｔａｎΨ（ω），ｃｏｓΔ（ω）］谱到［Ψ（ω），Δ（ω）］谱的转换。

Spectroscopic ellipsometry is a useful technique for studying surfaces and thin films. It has been used to determine the real part and imaginary part of indices and thicknesses of thin layer synchronically. However, photometric ellipsometer can only measure cos Δ, cannot determine directly the value of Δ at each wavelength. We apply the KramersKronig transformation relation to complex reflection ratio and derive ΨΔ relation. As an example, we approach a single layer film on a substrate.