Infrared reflectance of thin aluminum nitride films on various substrates

Abstract

The measured room-temperature infrared reflectance at near-normal incidence of thin AlN films deposited by metalorganic chemical vapor deposition on various substrates is compared with calculated spectra based on Lorentz oscillator models for the reststrahl regions with parameters obtained from the literature. The effects of film and substrate anisotropy and non-normal incidence are included. The contribution of AlN can be analyzed even when the substrate and/or a thin overlayer have overlapping reflection bands. It is possible to obtain information on the thickness and other properties of the AlN films.