Investigation of the effect of cerium doping on the electrical properties and leakage current behavior of lead zirconate thin films derived by the sol-gel method

Official URL: http://dx.doi.org/10.1111/j.1551-2916.2008.02858.x

Undoped and cerium (Ce)-doped (1 and 5 mol%) antiferroelectric thin films were obtained by a sol-gel process. All lead zirconate, PbZrO3 (denoted as PZ), films crystallized in the perovskite phase with a full [111] pseudocubic orientation and with a uniform microstructure. X-ray photoelectron spectroscopic investigations revealed that the oxidation state of Ce is 3+ leading to an A-site donor doping. Ce doping causes a decrease in the dielectric constant from 200 to 155 and an increase in the forward switching fields from 275 to 296 kV/cm. However, it also leads to a significant decrease in the leakage current density and this effect is more pronounced for the 5% doping case, where an order of magnitude lower leakage current is obtained compared with the undoped PZ. Analyses of leakage current behavior indicate dominance of a space charge limited current type leakage current and also a possible contribution from a Poole-Frenkel type emission in certain temperature or field regimes.