Shape transition of nanostructures created on Si(1 0 0) surfaces after MeV implantation

We have studied the modification in the surface morphology of the Si(1 0 0) surfaces after 1.5 MeV Sb implantation. Scanning probe microscopy has been utilized to investigate the ion implanted surfaces. We observe the formation of nanosized defect features on the Si surfaces for the fluences of 1 × 1013 ions/cm2 and higher. These nanostructures are elliptical in shape and inflate in size for higher fluences. Furthermore, these nanostructures undergo a shape transition from an elliptical shape to a circular-like at a high fluence. We will also discuss the modification in surface roughness as a function of Sb fluence.