The Bi1.5ZnNb1.5O7 pyrochlore was prepared by the polymeric precursor method. The films were deposited by dip coating on fluorine-doped tin oxide (FTO)-coated glass, fused quartz, and Pt/Ti/SiO2/Si(100) substrates. The films deposited on FTO-coated glass were annealed at temperatures ranging from 400 to 550 degrees C and from 500 to 800 degrees C, for fused quartz and Pt/Ti/SiO2/Si(100) substrates. Atomic force microscopy images revealed the surface morphology of the films as a function of the annealing temperature. X-ray difftaction detected the cubic pyrochlore in films treated above 450 degrees C, and full crystallization occurred at 700 degrees C. The films showed a high [I I I] orientation independently of the substrate, whereas those deposited on fused quartz showed the highest orientation. The optical band gap, calculated from the transmission measurements, ranged from 3.9 to 3.2 eV as a function of the temperature and the crystallite size. (c) 2005 Elsevier B.V All rights reserved.