Infrared Polarized Reflection Spectra of SrTiO 3 Thin Films on Metal/Si

The dielectric properties in the infrared region of SrTiO 3 thin film on Pd/Si were studied using reflectance spectra of radiation polarized parallel to the incident plane. The absorption bands of LO (optical phonon) modes increase linearly with increasing incident angle. Maximum sensitivity can be obtained using an incident angle of about 60∼85°. There is sufficient sensitivity at the film thickness of less than 10 nm. These results suggest that p -polarized reflection spectroscopy is a promising technique for estimating dielectric properties for very thin SrTiO 3 films on metal/Si.