High permittivity SrHf0.5Ti0.5O3 films grown by pulsed laser deposition

High permittivity SrHf0.5Ti0.5O3 films (k=62.8) have been deposited on (001) Nb–SrTiO3 single crystal conducting substrates by pulsed laser deposition. The SrHf0.5Ti0.5O3 films grow epitaxially with atomically smooth surfaces (root mean square roughness 4.8 A) and a c-axis orientation parallel to the substrate. The measured band gap of SrHf0.5Ti0.5O3 is 3.47 eV compared with 3.15 eV in SrTiO3. Under an applied electric field of 600 kV/cm, the leakage current density of the SrHf0.5Ti0.5O3 films is 4.63×10−4 A/cm2. These attractive dielectric properties and enhanced band gap values make SrHf0.5Ti0.5O3 a promising candidate for high-k dielectric applications in silicon-based integrated circuits.