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

作者：Romanyuk O^*; Fernandez Garrido S; Jiricek P; Bartos I; Geelhaar L; Brandt O; Paskova T

来源：Applied Physics Letters, 2015, 106(2): 021602.

DOI：10.1063/1.4905651

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.

• 出版日期2015-1-12