Oriented LiNbO3 thin films were prepared using a polymeric precursor solution deposited on (0001) sapphire substrate by spin coating and crystallized in a microwave oven. Crystallization of the films was carried out in a domestic microwave oven. The influence of this type of heat treatment on the film orientation was analyzed by X-ray diffraction and electron channeling patterns, which revealed epitaxial growth of films crystallized at 550 and 650 degreesC for 10 min. A microstructural study indicated that the films treated at temperatures below 600 degreesC were homogeneous and dense, and the optical properties confirmed the good quality of these films. (C) 2003 Elsevier Science B.V. All rights reserved.