☆ 4.6 Article

Non-destructive assessment of the polarity of GaN nanowire ensembles using low-energy electron diffraction and x-ray photoelectron diffraction

APPLIED PHYSICS LETTERS (2015)

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APPLIED PHYSICS LETTERS
卷 106, 期 2, 页码 -

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AMER INST PHYSICS
DOI: 10.1063/1.4905651

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Physics, Applied

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  1. Academy of Sciences of the Czech Republic [M100101201]
  2. NSF [DMR-1207075]

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We investigate GaN nanowire ensembles spontaneously formed in plasma-assisted molecular beam epitaxy by non-destructive low-energy electron diffraction (LEED) and x-ray photoelectron diffraction (XPD). We show that GaN nanowire ensembles prepared on AlN-buffered 6H-SiC(000 (1) over bar) substrates with well-defined N polarity exhibit similar LEED intensity-voltage curves and angular distribution of photo-emitted electrons as N-polar free-standing GaN layers. Therefore, as in the case of GaN layers, LEED and XPD are found to be suitable techniques to assess the polarity of GaN nanowire ensembles on a macroscopic scale. The analysis of GaN nanowire ensembles prepared on bare Si(111) allows us to conclude that, on this non-polar substrate, the majority of nanowires is also N-polar. (C) 2015 AIP Publishing LLC.

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