Preparation And Electrical Properties Of Pb(Zr_0.52Ti_0.48)O₃/LaNiO₃ Nanocomposite Films

Lead zirconate titanate(Pb(Zr,Ti)O₃)ferroelectric thin film material has been widely used in nonvolatile memory,micro piezoelectric motor,thin film capacitor and other integrated devices due to its excellent ferroelectric,dielectric and other functional characteristics.In recent years,with the continuous development of electronic components toward miniaturization and integration,single-component ferroelectric materials have been unable to meet the needs of modern industry and production.In this paper,Pb(Zr_0.52Ti_0.48)O₃(PZT)and La Ni O₃(LNO)were attempted to form a composite film,which is expected be an appropriate system to improve the electrical properties of ferroelectric materials.The main research contents and results of this paper are as follows.PZT/LNO/PZT sandwich composite films were successfully prepared by sol-gel method.The effects of LNO thickness on the microstructure and dielectric properties of the composite films were investigated.The results show that the perovskite grains of the upper PZT grow along the epitaxy of the LNO interlayer when the LNO layer is inserted into the PZT films.The electrical properties of PZT/LNO/PZT composite films are significantly improved due to the in-plane pressure effect on the upper PZT layer and the reduction of leakage current caused by the oxygen vacancy at the PZT/LNO interface.When the thickness of LNO layer is 140 nm,the PZT/LNO_{140 nm}/PZT composite films possesses the best remnant polarization and dielectric constant,which are 43.3?C/cm² and 1841,respectively,which are 298%and 116%higher than that of pure PZT films under the same electric field intensity.PZT/LNO alternating nanocomposite films were prepared by sol-gel method.According to the different composite ways,PZT/LNO multilayer nanocomposite films and multilayer film capacitors were prepared respectively.The results show that with the increase of alternate layers of PZT and LNO,the in-plane compressive strain effect of PZT and the oxygen vacancy effect at the interface of PZT/LNO are further amplified,and the electrical properties of PZT/LNO multilayer nanocomposite films are significantly improved.When the number of composite layers is 7 and the test voltage is 9 V,the remnant polarization strength of PZT/LNO multilayer nanofilms can reach 27.1?C/cm²,and the dielectric constant is 2050,which is 149%and 141%higher than that of pure PZT.The PZT/LNO multilayer film capacitor was prepared with LNO as the inner electrode and PZT as the dielectric layer.The design of the submicron multilayer film capacitor was realized.With the increase of the number of layers of the film capacitor,the capacitance and remnant polarization strength of the film capacitor increased.The capacitance of LNO/PZT/LNO thin film capacitor is 8.6 n F,and that of LNO/PZT/LNO/PZT/LNO thin film capacitor can reach 22.5 n F.