In this work, we report the preparation of lanthanum-modified lead zirconate titanate (PLZT) thin films by RF magnetron sputtering on platinized silicon (Pt/Ti/SiO2/Si) substrate. Sputtering was done in pure argon at 100 W RF power without external substrate heating. X-ray diffraction studies were performed on the films to study the effect of post-deposition furnace annealing temperature and time on the perovskite phase formation of PUT. Annealing at 610 degrees C for 2 h was found to be optimum for the preparation of PLZT films in pure perovskite phase. The effect of different annealing conditions on surface morphology of the films was examined using AFM. The dielectric, ferroelectric and electrical properties of these films were also investigated in detail as a function of different annealing conditions. The pure perovskite film exhibits better properties than the other films which have some fraction of unwanted pyrochlore phase. The remanent polarization for pure perovskite film was found to be similar to 29 mu C/cm(2) which is almost double compared to the films having mixed phases. The dc resistivity of the pure perovskite film was found to be 7.7 x 10(10) Omega cm at the electric field of similar to 80 kV/cm. (c) 2007 Elsevier Ltd. All rights reserved.