La-modified lead zirconate titanate Pb1.075La0.025(Zr0.95Ti0.05)O-3, antiferroelectric thin films are fabricated by excimer laser ablation technique on Pt/Ti/SiO2/Si substrates. The measured dielectric constant and dissipation factor are 642 and 0.021 at room temperature, respectively, and Curie temperature is 196 degreesC. The antiferroelectric double hysteresis loops of Pb1.075La0.025(Zr0.95Ti0.05)O-3 film are confirmed by measuring the polarization vs. the electric field. With increasing temperature, the double hysteresis loop behavior is reduced and gradually becomes a loose single ferroelectric hysteresis loop. The complex dielectric constants and a.c. conductivities are measured as a function of frequency (10(-2)-10(6) Hz) and temperature (25-250 degreesC) in order to investigate the influence of microstructure on the charge transport mechanism. We observe the strong low-frequency dielectric dispersion due to migration of thermally activated oxygen vacancies at higher temperature above 175 degreesC. The activation energy calculated from the a.c. conductivity is 0.63 eV (C) 2003 Elsevier B.V. All rights reserved.