Using a field emission gun based scanning electron microscopy, we report the formation of nanodots on the InP surfaces after bombardment by 100 keV Ar+ ions under off-normal ion incidence (30 degrees and 60 degrees with respect to the surface normal) condition in the fluence range of 1 x 10(16) to 1 x 10(18) ions cm (2). Nanodots start forming after a threshold fluence of about 1 x 10(17) ions cm (2). It is also seen that although the average dot diameter increases with fluence the average number of dots decreases with increasing. uence. Formation of such nanostructured features is attributed due to ion-beam sputtering. X-ray photoelectron spectroscopy analysis of the ion sputtered surface clearly shows In enrichment of the sputtered InP surface. The observation of growth of nanodots on the Ar+-ion sputtered InP surface under the present experimental condition matches well with the recent simulation results based on an atomistic model of sputter erosion. (C) 2009 Elsevier B.V. All rights reserved.