A modified sol-gel technique has been developed for the preparation of PZT thin films on Pt(1 1 1)/Ti/SiO2/Si(1 0 0) substrates. The technique uses zirconium nitrate to substitute for the conventional Zr-alkoxides, which enhances the stability of the precursor solution and simplifies the sol-gel processing significantly. Using a modified precursor solution and rapid thermal annealing (RTA) process, highly(1 1 1) oriented PbZr0.5Ti0.5O3 (PZT 50/50) thin films are obtained even at a low annealing temperature of 550 degrees C. The low-temperature processing is assisted by a layer-by-layer annealing method. The PZT 50/50 thin film annealed at 550 degrees C showed a well-saturated hysteresis loop at an applied electric field of 200 kV/cm with P-r and E-e of 11 mu C/cm(2) and 45 kV/cm, respectively. The dielectric constant and dielectric loss of the him are 520 and 0.023, respectively.