Multilayered structure of silicon oxinitrides and oxides for radiative cooling devices

Multilayered structures were prepared by growing SiOxNy and SiOx films upon Al substrates. Different stoichiometries of the oxinitride layers were obtained by a reactive R.F sputtering technique. The infra-red reflectance experiments show that such multilayered structures should be better adapted for application to radiative cooling devices than single layers made with the same materials. This is explained by the presence of strongly absorbing radiative surface and interface modes which appear in the Reststrahlen frequencies because of the multilayered geometry. We performed ATR experiments so as to detect the presence of these modes and to demonstrate their correlation with the reflectance spectra.