GaN nanowire templates for the pendeoepitaxial coalescence overgrowth on Si(111) by molecular beam epitaxy

Dogan, P.; Brandt, O.; Pfüller, Carsten; Bluhm, A K; Geelhaar, Lutz; Riechert, H.

doi:10.1016/j.jcrysgro.2010.12.081

Cited by 20 publications

(13 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to the wide range of conditions, the different NW samples exhibited incubation times between a few minutes and hours as well as different NW densities, average NW diameters, and coalescence degrees. Further details on the growth conditions can be found elsewhere (sample A [37], B1-B4 [43], B5-B7 [44], C [30], and D [45]).…”

Section: Methodsmentioning

confidence: 99%

Nature of excitons bound to inversion domain boundaries: Origin of the 3.45-eV luminescence lines in spontaneously formed GaN nanowires on Si(111)

et al. 2016

Self Cite

View full text Add to dashboard Cite

We investigate the 3.45-eV luminescence band of spontaneously formed GaN nanowires on Si(111) by photoluminescence and cathodoluminescence spectroscopy. This band is found to be particularly prominent for samples synthesized at comparatively low temperatures. At the same time, these samples exhibit a peculiar morphology, namely, isolated long nanowires are interspersed within a dense matrix of short ones. Cathodoluminescence intensity maps reveal the 3.45-eV band to originate primarily from the long nanowires. Transmission electron microscopy shows that these long nanowires are either Ga polar and are joined by an inversion domain boundary with their short N-polar neighbors, or exhibit a Ga-polar core surrounded by a N-polar shell with a tubular inversion domain boundary at the core/shell interface. For samples grown at high temperatures, which exhibit a uniform nanowire morphology, the 3.45-eV band is also found to originate from particular nanowires in the ensemble and thus presumably from inversion domain boundaries stemming from the coexistence of Nand Ga-polar nanowires. For several of the investigated samples, the 3.45-eV band splits into a doublet. We demonstrate that the higher-energy component of this doublet arises from the recombination of two-dimensional excitons free to move in the plane of the inversion domain boundary. In contrast, the lower-energy component of the doublet originates from excitons localized in the plane of the inversion domain boundary. We propose that this in-plane localization is due to shallow donors in the vicinity of the inversion domain boundaries.

show abstract

Section: Methodsmentioning

confidence: 99%

Nature of excitons bound to inversion domain boundaries: Origin of the 3.45-eV luminescence lines in spontaneously formed GaN nanowires on Si(111)

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…For sample 1 (2), GaN NWs were subsequently grown for 3 h at a substrate temperature of 780 (820) • C and N rich conditions, resulting in NW arrays with an average length of 1.0 (1.6) µm. [10] High-resolution XRD measurements were performed at a temperature of 27 • C using a Panalytical X-Pert PRO in strain-free GaN. [12,13] Sample 1 exhibits a linewidth of 3.7 meV, more than twice larger than the one observed for sample 2 (1.6 meV).…”

Section: Methodsmentioning

confidence: 99%

Macro- and micro-strain in GaN nanowires on Si(111)

Jenichen

Brandt²,

Pfüller³

et al. 2011

Nanotechnology

View full text Add to dashboard Cite

We analyze the strain state of GaN nanowire ensembles by x-ray diffraction. The nanowires are grown by molecular beam epitaxy on a Si(111) substrate in a self-organized manner. On a macroscopic scale, the nanowires are found to be free of strain. However, coalescence of the nanowires results in micro-strain with a magnitude from ± (0.015)% to ± (0.03)%. This micro-strain contributes to the linewidth observed in low-temperature photoluminescence spectra.

show abstract

“…16,17 Also, even during the growth stage, the gallium rate cannot be increased deliberately because this would eventually lead to an enhancement of radial growth, and the NW morphology would be lost. 38 …”

Section: Effects Of the Gallium Ratementioning

confidence: 99%