New opportunities with nanowires

Summary form only given. Light emission from Si, would allow integration of electronic and optical functionality in the main electronics platform technology, but this has been impossible due to the indirect band gap of Si. This talk will discuss 2 different approaches, using unique properties of nanowires, to realize light emission from Si-based compounds. In the first route, the paper focuses on the fabrication of defect-free GeSn compounds. The growth mechanism is discussed, the structural properties are investigated by electron microscopy and atom probe tomography and the temperature dependent optical properties are studied. The second route concentrates on Si and Ge with a different crystal structure. Here, crystal structure transfer is employed, in which wurtzite GaP is used as a template to epitaxially grow SiGe compounds with the hexagonal crystal structure. With this method, defect free hexagonal SiGe shells and branches with tunable Ge concentration are gorwn. The structural and optical properties of these new crystal phases will be discussed. The author believes that these new 3-dimensional epitaxial nanostructures have great potential to integrate optical functionality in Si technology.