Highly c-axis oriented Pb(Zr, Ti)O3 thin films grown on Ir electrode barrier and their electrical properties

We have investigated the structural and electrical properties of sol-gel derived ${\mathrm{Pb(Zr, Ti)O}}_{\mathrm{3}}$ (PZT) thin films deposited on Ir electrode barrier $({\mathrm{Ir/poly-Si/SiO}}_{\mathrm{2}}\mathrm{/Si}\mathrm{).}$ Owing to the interface-controlled growth, highly c-axis oriented perovskite PZT thin films were obtained for the postdeposition annealing temperature of 580 °C. Additionally, we found that the ferroelectric properties of ${\mathrm{IrO}}_{\mathrm{2}}\mathrm{/PZT/Ir/poly-Si}$ capacitors were remarkably changed by the partial pressure of oxygen during the deposition of ${\mathrm{IrO}}_{\mathrm{2}}$ top electrodes, which could be due to the enhanced reaction of ${\mathrm{IrO}}_{\mathrm{2}}$ with PZT by the oxygen ion bombardments. Remanent polarization and coercive field of ${\mathrm{IrO}}_{\mathrm{2}}\mathrm{/PZT/Ir/poly-Si}$ capacitor with the top electrodes deposited at $P_{{\mathrm{O}}_{\mathrm{2}}}\text{=1\hspace{0.05em}}\mathrm{mTorr}$ was 20 μC/cm² and 30 kV/cm, respectively, and showed negligible polarization fatigue up to ${10}^{11}$ switching repetitions. The leakage current density at a field of 80 kV was ${\text{5×10}}^{\text{−8}} {\mathrm{A/cm}}^{\mathrm{2}}.$