Embodiments of the invention include a method for fabricating a SiGe fin and the resulting structure. A SOI substrate is provided, including at least a silicon layer on top of a BOX. At least one fin upon a thin layer of silicon and a hard mask layer over the at least one fin is formed using the silicon layer on top of the BOX. A SiGe layer is epitaxially grown from exposed portions of the fin and the thin layer of silicon. Spacers are formed on sidewalls of the hard mask. Regions of the SiGe layer and the thin layer of silicon not protected by the spacers are etched, such that portions of the BOX are exposed. A condensation process converts the fin to SiGe and to convert the SiGe layer to oxide. The hard mask, the spacers, and the oxide layer are removed.