AFM Study on the Formation Mechanism and Microstructure of Ni Atomic Aggregates on Liquid Substrates

Abstract

We study the formation mechanism and microstructure of nickel (Ni) atomic aggregates on the silicone oil surfaces by atomic force microscopy (AFM). Initially, the deposited atoms nucleate and form the compact clusters on the liquid surfaces. Then they perform Brownian motion and adhere upon impact. Finally the branched aggregates are formed. The Ni aggregates exhibit granular structure. The mean size of the granularities in the aggregates is of the order of 10 nm and it decreases with the nominal film thickness. The experiment shows that the Ni aggregates perform a directional diffusion towards the sample edge. The interpretation for this phenomenon is presented.

Anomalous Kinetic Roughening of Nanostructured Ag Islands on Liquid Surfaces

“…Due to the relatively weak interaction between the Ag atoms and the substrate (oil molecules), granule formation is commonly resulted in the thin film system on oil surfaces. 17,20) As we have concluded above, the shape of the granule is plateau for d ¼ 1:0 nm, which is resulted from the characteristic interaction between the deposition Ag atoms and the liquid molecules. In this case, the shadowing effect happens frequently on the granule surfaces and then the surfaces become rougher.…”

“…2(c) and 2(d) is around 50.0 nm, indicating È g is approximately independent of d. This observation does not meet the findings in Ni and Al systems, where the mean diameter of Ni granule is below 20.0 nm and the granule diameter decreases with d in Al system. 19,20) These discrepancies may be resulted from the differences of the absorption energy of these three elements on the oil surface. Combining the average height obtained from Figs.…”

Growth Mechanism and Microstructure of Al Films Deposited on Ionic Liquid Surfaces

“…Over the past decade, vapor phase deposition of metals on silicone oil substrates has been studied systematically. [4][5][6][7][8] The experiments show that the films deposited on the liquid substrates may exhibit characteristic surface morphologies and plentiful physical properties. 5,6,[9][10][11] All the anomalous properties of these free sustained films are closely related to liquid substrates surfaces, because the surface types define the physical properties of objects including internal stress, interaction among the atoms, friction, collision and so on.…”