Epitaxial Catalyst-Free Growth of InN Nanorods onc-Plane Sapphire

Abstract

We report observation of catalyst-free hydride vapor phase epitaxy growth of InN nanorods. Characterization of the nanorods with transmission electron microscopy, and X-ray diffraction show that the nanorods are stoichiometric 2H–InN single crystals growing in the [0001] orientation. The InN rods are uniform, showing very little variation in both diameter and length. Surprisingly, the rods show clear epitaxial relations with thec-plane sapphire substrate, despite about 29% of lattice mismatch. Comparing catalyst-free with Ni-catalyzed growth, the only difference observed is in the density of nucleation sites, suggesting that Ni does not work like the typical vapor–liquid–solid catalyst, but rather functions as a nucleation promoter by catalyzing the decomposition of ammonia. No conclusive photoluminescence was observed from single nanorods, while integrating over a large area showed weak wide emissions centered at 0.78 and at 1.9 eV.

Review of recent progress of III-nitride nanowire lasers

“…119,120 Recently, significant efforts have already been devoted to the development of various InGaN NW heterostructures including core-shell, 81,121 well/disk-in-a-wire, 122,123 and dot-in-a-wire 12,66 based nanostructures, wherein large bandgap GaN or AlGaN layers are often employed as the barrier or the shell structures to provide effective radial and/or axial carrier confinement. Currently, various InN nanostructures, such as nanocrystals, 124 nanocolumns, 125 nanorods, 126 NWs, 96 nanotubes, nanotips, 127 and nanobelts, 36 have been extensively reported.…”

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

“…Compared with InN bulk materials and films, one-dimensional (1D) InN nanostructures have been rarely investigated due to its low decomposition temperature. Some efficient methods including chemical vapor deposition (CVD) [5][6][7], epitaxial growth [8][9][10], solvothermal synthesis [11], single-source precursors [12,13] and direct nitridation [14] have been successfully applied to the synthesis of 1D InN. Among these methods, CVD and epitaxial growth are most efficient since the synthesized products are well crystalline and rather uniform in size.…”

Structure of Co-2 × 2 nanoislands grown on Ag/Ge(111)-√3 × √3 surface studied by scanning tunneling microscopy

“…Nowadays, in the face of tremendous progress in device miniaturization, the possibility to manipulate the properties of the surface seems to be particularly attracting. In principle, it may be achieved by depositing foreign atoms onto the surface, as it is known that numerous properties of the resultant epitaxial layers, such as lattice constant or electric conductance, are quite different from those of the substrate [ 3 - 6 ].…”