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/cm(2) is needed, whereas around 0.1 Torr, near stoichiometry can be reached for laser energy densities from 0.9 to 2.3 J/cm(2). The kinetic energy of the ablated species is considered an important factor in affecting the film stoichiometry. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4717984]