Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Ion beam irradiation can produce different patterns on semiconductor surface. While the surface is amorphized at low temperatures, the surface remains crystalline above the dynamic recrystallization temperature. Reverse Epitaxy leads to pattern formation, which is driven by diffusion of vacancies and adatoms on the surface, above this temperature. The mechanisms of Reverse Epitaxy epitaxy are quite similar to mound formation in homoepitaxial growth. The surface is destabilized in both cases by an effective uphill diffusion current driven by Ehrlich-Schwoebel barriers. The patterns formed depend of step formation energies, diffusion on terraces, and Ehrlich-Schwoebel barriers, which all are anisotropic. Their anisotropy is determined by the surface symmetry. By changing the surface symmetry the resulting patterns are be changed.