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N-type doping and morphology of GaAs nanowires in Aerotaxy

Metaferia, Wondwosen LU ; Sivakumar, Sudhakar LU ; Persson, Axel R. LU ; Geijselaers, Irene LU ; Wallenberg, L. Reine LU ; Deppert, Knut LU ; Samuelson, Lars LU and Magnusson, Martin H. LU (2018) In Nanotechnology 29(28).
Abstract

Controlled doping in semiconductor nanowires modifies their electrical and optical properties, which are important for high efficiency optoelectronic devices. We have grown n-type (Sn) doped GaAs nanowires in Aerotaxy, a new continuous gas phase mass production technique. The morphology of Sn doped nanowires is found to be a strong function of dopant, tetraethyltin to trimethylgallium flow ratio, Au-Ga-Sn alloying, and nanowire growth temperatures. High temperature and high flow ratios result in low morphological quality nanowires and in parasitic growth on the wire base and surface. Alloying and growth temperatures of 400 °C and 530 °C, respectively, resulted in good morphological quality nanowires for a flow ratio of TESn to TMGa up... (More)

Controlled doping in semiconductor nanowires modifies their electrical and optical properties, which are important for high efficiency optoelectronic devices. We have grown n-type (Sn) doped GaAs nanowires in Aerotaxy, a new continuous gas phase mass production technique. The morphology of Sn doped nanowires is found to be a strong function of dopant, tetraethyltin to trimethylgallium flow ratio, Au-Ga-Sn alloying, and nanowire growth temperatures. High temperature and high flow ratios result in low morphological quality nanowires and in parasitic growth on the wire base and surface. Alloying and growth temperatures of 400 °C and 530 °C, respectively, resulted in good morphological quality nanowires for a flow ratio of TESn to TMGa up to 2.25 ×10-3. The wires are pure zinc-blende for all investigated growth conditions, whereas nanowires grown by metal-organic vapor phase epitaxy with the same growth conditions are usually mainly Wurtzite. The growth rate of the doped wires is found to be dependent more on the TESn flow fraction than on alloying and nanowire growth temperatures. Our photoluminescence measurements, supported by four-point probe resistivity measurements, reveal that the carrier concentration in the doped wires varies only slightly (1-3) ×1019 cm-3 with TESn flow fraction and both alloying and growth temperatures, indicating that good morphological quality wires with high carrier density can be grown with low TESn flow. Carrier concentrations lower than 1019 cm-3 can be grown by further reducing the flow fraction of TESn, which may give better morphology wires.

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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Aerotaxy, GaAs nanowires, n-type doping
in
Nanotechnology
volume
29
issue
28
publisher
IOP Publishing
external identifiers
  • scopus:85047780465
ISSN
0957-4484
DOI
language
English
LU publication?
yes
id
d7bdcdc2-7ba8-44ec-9b8d-d6a079b7aff9
date added to LUP
2018-06-13 15:11:18
date last changed
2018-06-14 03:00:06
@article{d7bdcdc2-7ba8-44ec-9b8d-d6a079b7aff9,
  abstract     = {<p>Controlled doping in semiconductor nanowires modifies their electrical and optical properties, which are important for high efficiency optoelectronic devices. We have grown n-type (Sn) doped GaAs nanowires in Aerotaxy, a new continuous gas phase mass production technique. The morphology of Sn doped nanowires is found to be a strong function of dopant, tetraethyltin to trimethylgallium flow ratio, Au-Ga-Sn alloying, and nanowire growth temperatures. High temperature and high flow ratios result in low morphological quality nanowires and in parasitic growth on the wire base and surface. Alloying and growth temperatures of 400 °C and 530 °C, respectively, resulted in good morphological quality nanowires for a flow ratio of TESn to TMGa up to 2.25 ×10<sup>-3</sup>. The wires are pure zinc-blende for all investigated growth conditions, whereas nanowires grown by metal-organic vapor phase epitaxy with the same growth conditions are usually mainly Wurtzite. The growth rate of the doped wires is found to be dependent more on the TESn flow fraction than on alloying and nanowire growth temperatures. Our photoluminescence measurements, supported by four-point probe resistivity measurements, reveal that the carrier concentration in the doped wires varies only slightly (1-3) ×10<sup>19</sup> cm<sup>-3</sup> with TESn flow fraction and both alloying and growth temperatures, indicating that good morphological quality wires with high carrier density can be grown with low TESn flow. Carrier concentrations lower than 10<sup>19</sup> cm<sup>-3</sup> can be grown by further reducing the flow fraction of TESn, which may give better morphology wires.</p>},
  articleno    = {285601},
  author       = {Metaferia, Wondwosen and Sivakumar, Sudhakar and Persson, Axel R. and Geijselaers, Irene and Wallenberg, L. Reine and Deppert, Knut and Samuelson, Lars and Magnusson, Martin H.},
  issn         = {0957-4484},
  keyword      = {Aerotaxy,GaAs nanowires,n-type doping},
  language     = {eng},
  month        = {05},
  number       = {28},
  publisher    = {IOP Publishing},
  series       = {Nanotechnology},
  title        = {N-type doping and morphology of GaAs nanowires in Aerotaxy},
  url          = {http://dx.doi.org/},
  volume       = {29},
  year         = {2018},
}