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arXiv · 0808.0448

Ion induced segregation in gold nanostructured thin films on silicon

J. Ghatak·P. V. Satyam
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Abstract

We report a direct observation of segregation of gold atoms to the near surface regime due to 1.5 MeV Au2+ ion impact on isolated gold nanostructures deposited on silicon. Irradiation at fluences of 6x10^13, 1x10^14 and 5x10^14 ions cm-2 at a high beam flux of 6.3x1012 ions cm-2 s-1 show a maximum transported distance of gold atoms into the silicon substrate to be 60, 45 and 23 nm, respectively. At a lower fluence (6x1013 ions cm-2) transport has been found to be associated with the formation of gold silicide (Au5Si2). At a high fluence value of 5x10^14 ions cm-2, disassociation of gold silicide and out-diffusion lead to segregation of gold to defect - rich surface and interface region.

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J. Ghatak, P. V. Satyam. 2008-08-04. Ion induced segregation in gold nanostructured thin films on silicon. https://doi.org/10.1016/j.nimb.2008.08.012

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