The following works are base on the study of self assembly structures at the nanometric scale. At this scale the surface energy have a major impact in this organization. For a better understanding of this mechanism we studied different Silicon-Germanium base structures. We experimentally studied the crystalline or amorphous growth on different types of substrates (amorphous: SiO2, crystalline: Si or SOI). Some of these substrates were nano-structured using a focused ion beam using gallium source or gold-silicon source. In addition, we were able to use different surfaces such as TiO2 or porous silicon to study the organization of the material small size pore(less than 50nm).