Fe-catalytic growth of ZnSe nanowires on a ZnSe(001) surface at low temperatures by molecular-beam epitaxy

We grew ZnSe needle-like nanowires on a ZnSeGaAs epilayer using Fe catalysts by means of molecular-beam epitaxy operated at low temperatures of 250-350°C, which are comparable to the usual temperatures for fabrication of ZnSe-based optoelectronic devices. The diameters at the tops of the nanowires ranged from 8 to 20 nm, and the typical length was about 200 nm. The number density of the nanowires was the order of 109 cm-2. A nanowire was the zinc blende structure and the longitudinal direction was 〈001〉, 〈111〉, 〈110〉, or 〈112〉. Photoluminescence spectroscopy implied that the optical property of the nanowires differs from that of the bulk crystals.