Author/Authors :
Siviero، نويسنده , , E. Barborini، نويسنده , , E and Boragno، نويسنده , , C and Buzio، نويسنده , , R and Gnecco، نويسنده , , C. Lenardi، نويسنده , , C and Piseri، نويسنده , , A.M. and Vinati، نويسنده , , S and Valbusa، نويسنده , , U and Milani، نويسنده , , P، نويسنده ,
Abstract :
The first stages of aggregation of low energy deposited carbon clusters on Ag(1 1 0) surface have been observed in situ by scanning tunnelling microscopy (STM). Sub-monolayer coverages of the substrate at room temperature have been obtained by using a supersonic neutral cluster beam with a mass distribution centered at an average of 900 atoms/cluster. We observe that clusters are able to diffuse on the surface and along steps, and organise themselves in compact islands principally located at step edges. Size of supported islands ranges from a few nm up to 40 nm. A statistical analysis based on several STM images shows that the island size follows a lognormal distribution law. Possible mechanisms involved in the diffusion and coalescence of carbon clusters on metallic surfaces are discussed.
