A system of transparent layers on top of an arbitrary underlying subsystem is considered. It is shown that the layer refractive index and the subsystem generalized Fresnel coefficients can be expressed in a simple and explicit way by the Fourier coefficients of the ellipsometric function ρ with the layer thickness as an expansion parameter. Thus the inverse ellipsometric problem is reduced to a much simpler and well-defined problem of finding these Fourier coefficients. Analysis shows that the ellipsometric inverse task must be considered separately, depending on whether the modulus of the s-polarization Fresnel coefficient for the ambient–layer interface is smaller than, equal to, or greater than that for the layer–substrate system.
© 1999 Optical Society of America
[Optical Society of America ]
(070.2590) Fourier optics and signal processing : ABCD transforms
(100.3190) Image processing : Inverse problems
(120.2130) Instrumentation, measurement, and metrology : Ellipsometry and polarimetry
(160.4760) Materials : Optical properties
Stoyan C. Russev, "Representation of the transparent layer–arbitrary substrate system parameters through the Fourier coefficients of the ellipsometric function," J. Opt. Soc. Am. A 16, 364-370 (1999)