Epitaxial Catalyst-Free Growth of InN Nanorods on<it>c</it>-Plane Sapphire

• Main Authors: Shalish I, Seryogin G, Yi W, Bao JM, Zimmler MA, Likovich E, Bell DC, Capasso F, Narayanamurti V
• Format: Article
• Language: English
• Published: SpringerOpen 2009-01-01
• Series: Nanoscale Research Letters
• Subjects: InN; Nanorods; Nanowires; Epitaxial growth; Sapphire; Catalyst-free; Ni
• Online Access: http://dx.doi.org/10.1007/s11671-009-9276-z

<p>Abstract</p> <p>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&#8211;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 the<it>c</it>-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&#8211;liquid&#8211;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.</p>