Highly (h00) oriented growth of SrTiO_3 thin films on Si(100) substrates by RF magnetron sputtering and their optical properties

摘要

SrTiO_3 (STO) thin films were grown on Si(100) substrates by RF magnetron sputtering. The substrate temperature was found to be a crucial parameter to obtain the highly (h00) oriented growth. At the substrate temperature of 700 ℃, STO thin films with the (h00)-orientation parameter (α_(h00)) of more than 93% were realized. Using vitreous silica as the substrate, the optical properties of STO thin film prepared at 700 ℃ were investigated by transmittance measurements. The fitting method was used to calculate the refractive index and the film thickness from the transparent region of the transmittance spectra. The dispersion of the refractive index was studied by considering a single electronic oscillator model. According to Tauc's law, the band gap of the film was found to be about 3.62 eV.