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تسجيل مستخدم جديدIon induced segregation in gold nanostructured thin films on silicon
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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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Enhanced diffusion of gold atoms into silicon substrate has been studied in Au thin films of various thicknesses (2.0, 5.3, 10.9 and 27.5 nm) deposited on Si(111) and followed by irradiation with 1.5 MeV Au2+ at a flux of 6.3x10^12 ions cm-2 s-1 and
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