Conduction mechanisms inBaTiO3thin films

We report the observation of two types of ${\mathrm{BaTiO}}_3$ thin films, one exhibiting the Poole-Prenkel transport mechanism and the other the field-enhanced Schottky mechanism. A factor-of-2 difference in the slope of the ${\log }_{10}$(I/V)-vs-${\mathit{V}}^{1/2}$ curves has been measured for these two types of films. Also, we have unambiguously determined that the static dielectric constant should be used to describe the carrier transport in these films.