Pb͑Zr, Ti͒O 3 ͑PZT͒ thin films with ͑100͒ preferred orientation were prepared using metalorganic chemical vapor deposition on LaNiO 3 ͑LNO͒ buffered platinized Si with thickness varying from 25-100 nm. The dependence of electrical properties of PZT films on thickness was studied using several techniques, including polarization-electric field (P-E), temperature variable currentvoltage (I-V), and capacitance-voltage (C-V) measurements. Because of the formation of Schottky barriers at ferroelectric/electrode interfaces, built-in electric fields are present. A progressive increment in carrier concentration and interfacial built-in electric field versus reducing PZT film thickness was observed, which is believed to be a dominant factor controlling the measured dielectric/ferroelectric properties. The higher built-in electric field in thinner PZT films would pin the dipoles at the interfacial region and retard the response of dipoles to the external electric field.

Pb(Zr 0.5 Ti 0.5 )O 3 thin films 25 nm in thickness were grown on LaNiO3/Pt/Ti buffered Si substrates at 600 °C by metalorganic chemical vapor deposition. P–E studies showed a remanent polarization value of 8 μC/cm2 with a coercive field of 200 kV/cm. In polarization fatigue studies, these films only showed slight degradation in remanent polarization up to 4×108 cycles (±3 V oscillation) before breakdown. Moreover, the effect of space charge on the C–V behavior of these films was illustrated I–V characteristics of these films were also described.

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Bilayer Ba0.6Sr0.4TiO3 - Ba0.4Sr0.6TiO3 and Ba0.4Sr0.6TiO3 - Ba0.6Sr0.4TiO3 thin films were deposited on the LaNiO3-buffered Pt/Ti/SiO2/Si substrates using pulse laser deposition method. A (100)preferred orientation was obtained. The structure was characterized using x-ray diffraction (XRD) and Raman spectroscopy. The leakage current, and dielectric permittivity versus temperature were characterized. Results indicated that the (100) preferred bilayer structure had less leakage current and smaller loss tangent, which was in favor of enhancing the quality of thin film used as microwave dielectrics.