Monolayer-isolated silver (Ag) nanodots with the average diameter down to 7 nm are synthesized on Al2O3/Si substrate by vacuum electron-beam evaporation followed by annealing at 400 degreesC in N-2 ambient. Metal-insulator-silicon (MIS) structures with Ag nanodots embedded in Al2O3 gate dielectric are fabricated. Clear electron storage effect with the flatband voltage shift of 1.3 eV is observed through capacitance-conductance and conductance-voltage measurements. Our results demonstrate the feasibility of applying Ag nanodots for nanocrystal floating-gate memory devices. (C) 2004 Elsevier B.V. All rights reserved.