Simultaneous characterization of detector and source imperfections in infrared ellipsometry

Optical components required for infrared (IR) ellipsometry have distinctly worse characteristics compared to those available for the visible spectrum. The calibration of the optical components used is therefore essential for obtaining reliable results. Here a powerful method is outlined to calibrate simultaneously the polarization characteristics of a source and detector through the synchronous rotation of two polarizers. The performance of this method is to a large degree independent of the quality of (commercially available) polarizers. This renders this method robust and highly suitable for the IR range. Moreover, it is also inherently insensitive toward a nonlinear response of the detector. This enables us to use this method as the first step in the quantification of component imperfections.