Stoichiometry of SrTiO3 films grown by pulsed laser deposition

We have investigated the effects of laser energy density and oxygen pressure on the cation stoichiometry of homoepitaxial (001) SrTiO3 thin film grown by pulsed laser deposition. A broad growth window was found for near stoichiometric, uniform SrTiO3 thin films. At oxygen pressures, at or below 10−2 Torr, laser energy density below around 1.0 J/cm2 is needed, whereas around 0.1 Torr, near stoichiometry can be reached for laser energy densities from 0.9 to 2.3 J/cm2. The kinetic energy of the ablated species is considered an important factor in affecting the film stoichiometry.