Self-organized Ordered Nanostructures by Ion Beam Sputtering

In the series of self-organized processes for the fabrication of nanostructures the pattern forma-tion during ion erosion of surfaces has attracted much interest in the last years. In the continuous sputtering process, induced by the bombardment with low-energy ions, periodic surface patterns appear in form of ripples under off-normal incidence or arrays of hexagonally ordered dots at normal incidence. The dimension of the pattern is related to the size of the typical collision cas-cade and lies in the range of ten to tens of nanometers, depending on ion energy. The self-organization mechanism relies on the interplay between a surface instability caused by the sput-tering, and surface diffusion processes. Regular ripple and dot array morphologies have been produced in this way on very different materials including semiconductors, insulators, and met-als, demonstrating the universality of the mechanism.