Formation of gold anostructures detected by SEM microscope

Gold nanostructures were prepared on silicon - Si(111) as a substrate. The substrates (1 × 1 cm2 of area) were cleaned with acetylacetone and then rinsed in ethanol. Thin Au films (with thicknesses in a range of 1.7–5.0 nm) were deposited using a table-top dc magnetron sputtering coater (EM SCD 500, Leica) under pure Ar plasma conditions (Argon, Air Products 99.999%). The Au target had 99.99% purity, the rate of Au layer deposition was about 0.4 nm·s−1 and the incident power was 32 W. The thickness of the films was measured in situ by a quartz crystal microbalance. To analyze the surface morphology of the samples, a FEI Quanta FEG 250 scanning electron microscope (SEM) operated at 10 kV was used. Samples with 1.2, 1.5 and 3.4 nm of initial Au layer anealed at 550 deg for 5, 10 and 15 minutes were measured.