Effect of SHI irradiation on the morphology of SnO2 thin film prepared by reactive thermal evaporation

SnO2 thin films prepared by reactive thermal evaporation on glass substrates were subjected to 120 MeV Ag9+ ion irradiation. The surface topography progression using the swift heavy ion irradiation was studied. It shows creation of unique surface morphologies and regular structures on the surface of the SnO2 thin film at particular fluences. Field Emission Scanning electron microscopy (FE-SEM) and Atomic force microscopy (AFM) are used for investigating the effect of Ag ions at different fluences on the surface of SnO2. The morphological changes suggest that ion assisted/induced diffusion process play a significant role in the evolution of nanostructures on SnO2 surface. The roughness increases from 9.4 to 14.9 with fluence upto 1 × 1012 ions/cm2 and beyond this fluence, the roughness decreases. Ion-beam induced recrystallization at lower fluences and amorphization or disordering of crystals at higher fluences are understood based on the thermal spike model.

► Topographical evolution by SHI irradiation with transition at particular fluence.
► Thermal energy shared via electron–electron coupling and lattice vibration.
► The sample irradiated with fluence of 1 × 1012 ions/cm2 shows the maximum roughness.