Controlled growth of highly uniform, axial/radial direction-defined, individually addressable InP nanowire arrays

We report on the systematically controlled growth of InP nanowire arrays by catalyst-free selective area metalorganic vapour phase epitaxy on partially masked InP(1 I 1)A substrates. The length, diameter, shape and position of the nanowires were precisely controlled by careful choice of the growth conditions and mask patterning. Manipulation of the growth conditions also enabled us to deliberately define the nanowire growth along either the axial or the radial direction, which has significant potential for the realization of novel nanostructures. Transmission electron microscopy studies revealed that the InP nanowires grown were single-crystalline with wurtzite crystal structure and the photoluminescence studies carried out at 4 K on InP nanowire arrays revealed a single intense emission peak with a significant blueshift. The controlled fabrication thus enabled the nanowires to be realized in a highly uniform manner as reproducibly identical structures and with perfect positioning in predetermined configurations, making them highly suitable for practical integration into nanodevices.