Highly oriented PbZr_0.3Ti_0.7O₃ thin film on LaNiO₃-coated Si substrate derived from a chemical solution technique

Highly (100)-oriented LaNiO₃ (LNO) films directly on Si substrates were prepared by a simple chemical solution technique using lanthanum nitrate and nickel acetate as the start material sources. Highly (100)-oriented PbZr_0.30Ti_0.70O₃ (PZT30/70) thin film was fabricated subsequently on the LNO-coated Si substrates using a modified sol-gel method. The orientation of the PZT and LNO thin films was characterized by X-ray diffraction (XRD). The resistivity of the LNO thin film at room temperature (300 K) is 7.6×10^-4 Ωcm. The remmant polarization (P_r) and coercive field (E_c) of the Pt/PZT/LNO/Si capacitor were 10.5-16.8 μC/cm² and 20.5-31.6 kV/cm with the variation of electric field (100-200 kV/cm). The values of dielectric constant and dissipation factor of 10 kHz were 700 and 0.019, respectively. After 10⁸ switching cycles, the net-switched polarization values of the capacitor drop to 95, 62, and 37% of their initial values under different electric fields ranging from 100 to 200 kV/cm, respectively.