An interconnected microstructural ZnAl2O4 film was prepared from a stoichiometric mixture of zinc nitrate and aluminium tri-secbutoxide using a sol-gel method. When the as-prepared films were annealed up to 800degreesC with a heating rate of 2degreesC/min, interconnected microstructural topography was developed through a series of processes: formation of interconnected threads and development of a full-area interconnected microstructure. The heating rate had a critical influence on the formation of interconnected microstructural ZnAl2O4 films and the mechanism for formation of this interconnected microstructure was speculated to be some preferential interactions along the organic chains within the gel precursor. (C) 2004 Elsevier B.V. All rights reserved.