No abstract

In 8-to 20-keV photon energy region, ruthenium and carbon thin films are used in multilayer monochromators. In the present study, this material combination is explored for X-ray waveguide applications in hard X-ray region. The structural parameters (thickness of each layer) of Ru/C/Ru waveguide structure are optimized to get maximum intensity enhancement of fundamental mode inside carbon guiding layer. A sample with optimized structural parameters is deposited using ion beam sputtering (IBS) technique and characterized using X-ray reflectivity (XRR) and grazing incidence X-ray fluorescence (GIXRF) techniques. The analysis suggests that the density of bottom Ru layer and carbon guiding layer is close to bulk density ($97% for Ru and $95% for carbon), whereas density of top Ru layer is slightly lower ($93% of bulk density). A $10% of thickness variation in top cladding layer along with marginal change in layer density deteriorate field enhancement in TE 0 mode by more than three times. Effect of thickness and density variation on waveguide (Ru [7 nm]/C [18 nm]/Ru [20 nm]) performance is discussed.

Zirconium oxide thin film serves as one of the potential material candidates in extreme ultraviolet/soft x-ray optics applications. The suitability of its application can be justified by investigating its optical performance in the working energy range. In this study, we have investigated the soft x-ray optical properties of a zirconium oxide thin film near the O K-edge region using the energy-dependent soft x-ray reflectivity (SXR) technique. The SXR and absorption measurements are performed using the Indus-2 soft x-ray reflectivity beamline BL-03. The optical constants (δ and β) in the energy range of 500–560 eV covering O K-edge are extracted by applying Kramers–Kronig relations. Experimentally obtained δ and β profiles show a prominent eg and t2g feature in the vicinity of O K-edge with the crystal field splitting of 2.9 eV. All features observed in the δ and β spectra are correlated with their electronic structure and composition of the zirconium oxide thin film. Details of correlation between structural and optical properties as determined by x-ray absorption spectroscopy, x-ray photoelectron spectroscopy, and SXR analyses are discussed.