Characteristics of Strain-Induced InxGa1−xAs Nanowires Grown on Si(111) Substrates

ABSTRACT: Large strain-energy arising from lattice mis-match allows one-dimensional heteroepitaxial growth of InxGa1−xAs on silicon substrates without any catalyst or pattern assistance. In this paper, we show that in contrast to nanowires (NWs) grown by metal-catalyzed vapor−liquid− solid mechanism, strain-induced InxGa1−xAs NWs have several unique morphological features including no tapering, slight bending, and composition-dependent NW height saturation. Although small fluctuation exists, no systematic composition variations are observed over the entire InxGa1−xAs NW length within the resolution of the energy-dispersive X-ray spectroscopy analysis. Bandgap engineering of semiconductors is essential to enhance the functionality of the optoelectronic devices.1 For example, bandgap-engineered InxGa1−xAs can cover the entire near