Dielectric function representation by B‐splines

Accurate dielectric function values are essential for spectroscopic ellipsometry data analysis by traditional optical model‐based analysis techniques. In this paper, we show that B‐spline basis functions offer many advantages for param‐ eterizing dielectric functions. A Kramers–Kronig consistent B‐spline formulation, based on the standard B‐spline recursion relation, is derived. B‐spline representations of typical semiconductor and metal dielectric functions are also presented. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)