Nanometer-scale An quantum dots have been assembled on SiO2 by controlling the reaction of raw materials to form a citrate Au sol and aminosilane/dithiol treated patterned Si wafer. Details of the formation mechanism have been studied. Three gold colloidal particles (similar to 15 nm), aligned in a chain to form a one-dimensional current path, were bridged on an 80 nm gap between the source and drain metal electrodes. The device exhibited a Coulomb blockade effect at 33 K. (C) 2004 American Vacuum Society.