Si-based nano-island arrays were fabricated on porous anodic alumina by two methods. In the first method, a thick silicon film was first deposited onto the surface with highly ordered bowl array prepared by anodizing an Al foil, followed by the formation of a polycrystalline silicon nano-island array on the surface close to the bowl array after dissolving aluminum. In the second method, porous anodization was performed on an Al thin film on Si and a SiO nano-island array was subsequently formed electrochemically. Time-resolved atomic force microscopy and photoluminescence were used to investigate the growth process as well as the mechanism of the growth process. Our proposed mechanism as well as assumptions made to formulate the model were found to be in agreement with the experimental results. © 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.