Insufficient oxidation in pulsed laser deposition

The influence of the ratio of oxygen atoms to ablated species in the ablation plume on the oxidation state of thin films was examined through the film growth of SrTiO3 by pulsed laser deposition. The amount of the ablated species was adjusted by changing the laser spot size on the target while keeping the oxygen pressure and laser energy density constant. The oxidation state is not defined by the background oxygen pressure during deposition. Instead, it is dominated by the oxidation which occurs when a burst of deposited species interacts with the oxygen atoms in the plume and incorporates oxygen ions into the lattice.