Physical properties of a nanocrystalline thin film is greatly influenced by its morphological and structural evolution. We try to understand the transition of SnO2 thin films from amorphous to nanocrystalline structure with XRD, IR, SEM, AFM and surface profiler studies. A 2D layer like structure resulting from quantum confinement is found for the films prepared at 400 degrees C. We observed a new IR band at 530 cm(-1) that was theoretically predicted and report it for the first time. A correlation of population of defects in SnO2 films with change in lattice parameters and FWHM of IR bands are reported. The electric and optical properties of the films have been discussed. (c) 2007 Elsevier B.V. All rights reserved.