In this study, ZnO films were deposited on silicon wafers patterned with micron-sized trenches in a flow type MOCVD reactor using DEZ-n-hexane and H2O as precursors. Scanning electron microscopy was used to measure the film thickness within the micro-trench. Using a modified model equation to fit the experimental growth rate data, we were able to determine the surface reaction rate constants, k(s), or the sticking coefficients, eta. At temperatures from 400 to 500 degrees C, eta from 0.5 to 0.6 was obtained. Interestingly, eta was decreased to 0.2 at higher temperatures of 700-750 degrees C. In order to verify if different growth species are present at low temperature of 400 degrees C and high temperature of 700 degrees C we employ a novel method to "capture" the intermediate species. Thermal analysis of the sample obtained at the reaction temperature of 400 degrees C revealed two endothermic peaks at 79 and 114 degrees C, while the sample obtained at 700 degrees C revealed three peaks at 84, 117 and 142 degrees C. (C) 2008 Elsevier B.V. All rights reserved.