Abstract
Ge surfaces were irradiated by Ar+ ions of 600 eV with and without a simultaneous Ge supply at various temperatures up to 200°C. The surfaces ion-irradiated without a Ge supply were characterized by conical protrusions, independent of the fabrication temperature. By contrast, densely distributed cones, nanobelts and nanowalls were formed on the surfaces ion-irradiated with a simultaneous Ge supply even at room temperature. Because the formation of those nanobelts and nanowalls was specific to sputtering with a Ge supply and enhanced by sample heating, it was concluded that the surface diffusion of the supplied Ge atoms played an essential role in their formation. Thus, it was believed that the ion irradiation method would open up a new route to fabricate low-dimensional nanostructures of semiconductors at low temperatures.
