Catalyst-free chemical vapor deposition route to InN nanowires and their cathodoluminescence properties

Abstract

InN nanowires were grown on 4H–SiC substrates by catalyst-free chemical vapor deposition method. The nanowires have wurtzite structure and the length is up to tens of micrometers. The growth process follows a typical self-catalyzed vapor–liquid–solid mechanism. The initial non-stoichiometric InNx droplets assist the one-dimensional growth of InN along the c axis. Cathodoluminescence spectra of an individual nanowire indicate two emission bands centered at 1.70 and 1.38eV, respectively. Burstein-Moss shift induced by high electron concentrations of the InN nanowires should be responsible for the 1.70eV emission band, and N vacancies may be the most probable cause for the cathodoluminescence emission at 1.38eV.