The trend predicted by Moore’s law sets forth strict requirements on the electronic properties of materials that cannot always be satisfied by conventional semiconductors. Thus, the last twenty years and, in particular, the first decade of this century have witnessed a progressive interest in materials and devices with reduced size and dimensionality. Nanostructures and nanomaterials have been considered the key development for next generation technology, due their ease of processing, new properties and compatibility with the existent silicon (Si) microelectronics. Great progresses have been made, in particular regarding the use of Si nanostructures in microelectronics, photonics, and photovoltaics.
However, the scaling down of semiconductor structures to nanometer sizes alone does not satisfy the need of new unique properties in a variety of applications. On the other hand, the manipulation through alloying together with the variation of the size provides a natural platform for the development and creation of materials that present the desired properties but, at the same time, can be easily integrated into the existent Si technology. A meaningful example of this possibility is given by the use of silicon–germanium (SiGe) nanostructures.