The influence of the ratio of oxygen atoms to ablated species in the a
blation plume on the oxidation state of thin films was examined throug
h the film growth of SrTiO3 by pulsed laser deposition. The amount of
the ablated species was adjusted by changing the laser spot size on th
e target while keeping the oxygen pressure and laser energy density co
nstant. The oxidation state is not defined by the background oxygen pr
essure during deposition. Instead, it is dominated by the oxidation wh
ich occurs when a burst of deposited species interacts with the oxygen
atoms in the plume and incorporates oxygen ions into the lattice. (C)
1995 American Institute of Physics.