A method is presented for simultaneously producing oriented silicon nanowire arrays and depositing gold on a silicon substrate from aqueous HF solution containing KAuCl4 near room temperature. Scanning electron microscopy, transmission electron microscopy and energy dispersive X-ray were used to characterize the morphologies, structure and compositions of the samples. Experimental results show that these silicon nanowires are single crystals and the growth of gold dendrites plays an important role in the formation of silicon nanowire arrays. Possible mechanism was proposed to explain the formation of silicon nanowire arrays based on local passivation of the silicon dissolution induced by the growth of Au nuclei. (C) 2003 Elsevier B.V. All rights reserved.