Structural and electronic properties of Si (111) and (001) nanowires: A theoretical study

In this work, our preliminary theoretical results for the structural and electronic properties of both Si (111) and (100) nanowires, with their lateral surfaces saturated with H or not, are shown. Our results show that, without the saturators, there is the formation of {110} facets to partly release the stress accumulated at lateral surfaces of the nanowires. These facets give rise to states close to the top of valence band and to the bottom of the conduction band that have character arising from both the occupied and empty Si-derived dangling bonds, respectively. Moreover, while the (111) nanowire have a direct band gap, with values within the visible range of the electromagnetic spectra, the (100) ones have an indirect band gap. (C) 2012 Published by Elsevier B.V. Selection and/or peer-review under responsibility of Universidade Federal de Juiz de Fora, Brazil.