A structural investigation of highly ordered catalyst- and mask-free GaN nanorods

作者:Figge S*; Aschenbrenner T; Kruse C; Kunert G; Schowalter M; Rosenauer A; Hommel D
来源:Nanotechnology, 2011, 22(2): 025603.
DOI:10.1088/0957-4484/22/2/025603

摘要

GaN nanorods were grown on r-plane sapphire substrates by a two-step approach. Nucleation sites for the nanorods were provided by the formation of AlN islands during nitridation in a metal organic vapor phase system. These islands are a-plane oriented as expected for nitride growth on r-plane sapphire. The nanorods themselves were grown by plasma assisted molecular beam epitaxy. The nanorods show an inclination towards the surface normal of 28.3 degrees and are highly ordered. Studies with high resolution x-ray diffraction polar plots reveal the epitaxial relationship between the substrate and nanorods as a c-direction growth on inclined m-plane facets of the nitridated islands. The determined lattice constants show nanorods which are strain free. The growth direction of the nanorods has been confirmed in a transmission electron microscope by convergent beam electron diffraction patterns to be in the N-polar [000 (1) over bar] direction.

  • 出版日期2011-1-14