Silica thin films were deposited by the redox reaction of an aqueous ammonium hexafluorosilicate solution with reducing agent: dimethylamine borane (DMAB) onto poly(ethylene terephthalate) (PET) substrate. The antireflection and transparent-enhancement effect of the films to PET substrate were investigated varying initial concentrations of DMAB. The surface and inner phase morphology of the silica films were characterized by means of atomic force microscopy and transmission electron microscopy. A model for the manner of the silica film growth according to aggregation of spherical granular of which the radius sizes are changed by DMAB concentration was proposed. (c) 2006 Elsevier B.V. All rights reserved.