Spectroscopic Ellipsometry on Metallic Gratings

Abstract

During the last decades light was successfully modelled by micro and nano structures such as photonic crystals, gratings, wave couplers, and, in past years, also negative index materials. For the visible range a further miniaturization of the feature sizes of these metamaterials is necessary. Advanced fabrication facilities as well as investigation techniques are required by science and industry. This chapter deals with spectroscopic ellipsometry (SE) applied to the investigation of metallic gratings and the comparison with theoretical simulations. The comparison of theoretical and experimental spectra of metallic gratings provides a useful basis for more complicated metamaterials, such as negative index materials. This analysis is shown in the beginning of this chapter. Deviations in the structure are identified and it is shown that RCWA and SE constitute a powerful combination to analyze nanostructures. It is followed by the study of surface plasmons on metallic grating which are excited due to the periodic structure. These excitation frequencies are clearly visible in the ellipsometric spectra due to a phase shift and the ratio of reflected intensities between \(s\) and \(p\) polarization.