Nano Express

Nanoscale Research Letters

, 4:532

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

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

  • I ShalishAffiliated withHarvard UniversityBen Gurion University Email author 
  • , G SeryoginAffiliated withHarvard University
  • , W YiAffiliated withHarvard University
  • , JM BaoAffiliated withHarvard UniversityUniversity of Houston
  • , MA ZimmlerAffiliated withHarvard University
  • , E LikovichAffiliated withHarvard University
  • , DC BellAffiliated withHarvard University
  • , F CapassoAffiliated withHarvard University
  • , V NarayanamurtiAffiliated withHarvard University

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.

Keywords

InN Nanorods Nanowires Epitaxial growth Sapphire Catalyst-free Ni