Ga-catalyzed growth of ZnSe nanowires and the cathodoluminescence and electric transport properties of individual nanowire

摘要

We developed a facile thermal evaporation method to fabricate zinc-blende ZnSe nanowires on GaAs substrates by using Ga as catalyst. The Ga catalyst originates from the reduction of the amorphous GaO_x layer pre-oxidized on surface of GaAs substrates. The cathodoluminescence (CL) spectra of an individual nanowire reveal a weak near-band-edge emission centered at 468 nm and a strong deep-level emission at 593 nm. The deep-level emission is assigned to self-activated luminescence induced by donor-acceptor pairs that are associated with intrinsic point defects: Zn vacancies and Zn interstitials. The electrical transport property of individual nanowire reveals that the current versus voltage curve remains linear relation even at high applied voltage, indicating that the conventional electric power dissipation cannot affect the electric transport properties of the nanowire.