Various silicon nanostructures (twofold chevrons and three- and fourfold spirals) were grown on silicon [111] substrates prepatterned with a two-dimensional square lattice of blocks with different block size and periodicity via ion beam induced glancing angle deposition at room temperature, in combination with a controlled substrate rotation. Top view and cross-section scanning electron microscopy pictures reveal that form, size, and periodicity of the structures are strongly dependent on the size and periodicity of the seeding space and differ widely from structures grown on plain substrates. It is shown that the growth of periodically arranged nanostructures, which is important for many possible applications, including photonic crystals, on prepatterned substrates is only possible if the periodicity of the seeding spaces matches the natural lateral dimensions of the structures grown on bare substrates. (c) 2007 American Vacuum Society.