  We discuss four important aspects of 1.5 MeV Au2+ ion-induced flux dependent
sputtering from gold nanostrcutures (of an average size 7.6 nm and height 6.9
nm) that are deposited on silicon substrates: (a) Au sputtering yield at the
ion flux of 6.3x10^12 ions cm-2 s-1 is found to be 312 atoms/ion which is about
five times the sputtering yield reported earlier under identical irradiation
conditions at a lower beam flux of 10^9 ions cm-2 s-1, (b) the sputtered yield
increases with increasing flux at lower fluence and reduces at higher fluence
(1.0x10^15 ions cm-2) for nanostructured thin films while the sputtering yield
increases with increasing flux and fluence for thick films (27.5 nm Au
deposited on Si) (c) Size distribution of sputtered particles has been found to
vary with the incident beam flux showing a bimodal distribution at higher flux
and (d) the decay exponent obtained from the size distributions of sputtered
particles showed an inverse power law dependence ranging from 1.5 to 2.5 as a
function of incident beam flux. The exponent values have been compared with
existing theoretical models to understand the underlying mechanism. The role of
wafer temperature associated with the beam flux has been invoked for a
qualitative understanding of the sputtering results in both the nanostructured
thin films and thick films.
