AES CHARACTERIZATION OF CONSTITUENTS’ OXIDATION STATE IN SPECTRALLY SELECTIVE TITANIUM-OXYNITRIDE COATINGS ON METALS FOR HIGH EFFICIENT SOLAR ABSORBERS

In this study, a surface-sensitive Auger Electron Spectroscopy (AES) was used to comprehensively characterize titanium-oxynitride coatings on metals for high efficient solar absorbers. Primary information obtained from the AES is chemical composition, but chemical state of the elements may also be estimated. Corroborative information about the coating’s structure was obtained from the estimate of Cu, Al and Ti oxidation state vs depth, also derived from the AES data. Ti/(O $+$ N) concentration ratios vs depth in TiO_XN_Y layer of the coatings on the Al and Cu substrate were also determined. Physical Vapor Deposition (PVD) was used to prepare TiO_XN_Y multilayered on Al and Cu substrates. Individual layer’s depth was in submicron domain. Deposition procedure and corresponding deposition parameters are presented. Optical properties (emittance, absorptance) of the coatings on both substrate types were also measured to confirm that coatings performed well their intended function (i.e. spectral selectivity).