Effect of hydrolysis on properties of PbZr_0.50Ti_0.50O₃ ferroelectric thin films derived from a modified sol-gel process

Lead zirconate titanate PbZr_0.50Ti_0.50O₃ (PZT) ferroelectric thin films were successfully deposited on Pt(111)/Ti/SiO₂/Si substrates by a modified sol-gel method using zirconium nitrate as a substitute for the conventional zirconium alkoxide. The precursor solutions were hydrolyzed with different H₂O/Pb ratios. The effect of hydrolysis ratios of the solution on the microstructure for the PZT thin films were investigated via X-ray diffraction (XRD) and atomic force microscopy (AFM) techniques. The XRD results show that the PZT films exhibit (111)-orientation and the degree of the (111)-orientation decreases with the increase of hydrolysis ratio. These results indicate that the ferroelectric behavior can be improved by an appropriate choice of H₂O/Pb ratio.