Effect of Zr/Ti Ratio in Targets on Electrical Properties of Lead Zirconate Titanate Thin Films Derived by Pulsed Laser Deposition on Template Layer

Using various targets of Pb(Zr x Ti 1- x )O 3 (PZT) with Zr/Ti ratios of 70/30, 58/42, 52/48, 45/55 and 30/70, PZT thin films were prepared by pulsed laser deposition on Pt/Ti/SiO 2 /Si(100) substrates with a template layer derived by the sol-gel process. The structure and crystalline phases of the PZT films relative to the Zr/Ti ratio were investigated by X-ray diffraction analysis. The effect of the Zr/Ti ratio in the targets on the electrical properties of the PZT thin films was investigated by measuring the polarization versus electric field hysteresis loop and the dielectric constant. It was found that the PZT films derived from the target with a Zr/Ti ratio of 45/55 exhibited better electric properties than those derived from the target with a Zr/Ti ratio of 52/48, and their composition was close to the morphotropic phase boundary composition. The remanent polarization and the coercive field of the film were 31.28 µC/cm 2 and 45.29 kV/cm, while the dielectric constant and dielectric loss tangent measured at 1 kHz were approximately 1069 and 0.08, respectively. It was clarified that the template layer derived by the sol-gel process can lower the annealing temperature in the pulsed laser deposition process, and improve the electrical properties of the PZT films.