The Ba(Zr-x,Ti1-x)O-3 (BZT) thin films on Pt(111)/Ti/SiO2/Si(100) substrates were fabricated by a sol-gel-hydrothermal (SGHT) process. The microstructural characteristics proved that the prepared BZT thin films with well-developed crystallinity and good surface morphology were converted from the amorphous phase to the perovskite phase at very low-temperature processing of 100-200 degrees C. The infrared optical properties of the BZT thin films have been investigated using an infrared spectroscopic ellipsometry in the wave number range of 800-4000 cm(-1) (2.5-12.5 mu m) by fitting the measured pseudodielectric functions with a three-phase model (Air/BZT/Pt), and a derived classical dispersion relation for the thin films. The optical constants of the thin films have been simultaneously obtained. (c) 2006 Elsevier B.V. All rights reserved.