Infrared dielectric properties of BaTiO3 ultrathin films

Using high accurate infrared spectroscopic ellipsometry, the infrared dielectric constants of BaTiO 3 ultrathin films are obtained in the temperature ranging from 20 to 150°C, which were deposited on Pt-Ti-SiO 2 -Si substrate by radio frequency magnetron sputtering. The high frequency dielectric function of the BaTiO 3 ultrathin films shows the temperature dependence from the tetragonal to the cubic phase transition. The results suggest that the temperature dependence of the BaTiO 3 ultrathin films' infrared dielectric properties should be considered in the technological applications and theoretical investigations.