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Structural Changes in a Single GaN Nanowire under Applied Voltage Bias

Lazarev, Sergey ; Dzhigaev, Dmitry LU orcid ; Bi, Zhaoxia LU orcid ; Nowzari, Ali LU ; Kim, Young Yong ; Rose, Max ; Zaluzhnyy, Ivan A. ; Gorobtsov, Oleg Yu ; Zozulya, Alexey V. and Lenrick, Filip LU orcid , et al. (2018) In Nano Letters 18(9). p.5446-5452
Abstract

GaN nanowires (NWs) are promising building blocks for future optoelectronic devices and nanoelectronics. They exhibit stronger piezoelectric properties than bulk GaN. This phenomena may be crucial for applications of NWs and makes their study highly important. We report on an investigation of the structure evolution of a single GaN NW under an applied voltage bias along polar [0001] crystallographic direction until its mechanical break. The structural changes were investigated using coherent X-ray Bragg diffraction. The three-dimensional (3D) intensity distributions of the NWs without metal contacts, with contacts, and under applied voltage bias in opposite polar directions were analyzed. Coherent X-ray Bragg diffraction revealed the... (More)

GaN nanowires (NWs) are promising building blocks for future optoelectronic devices and nanoelectronics. They exhibit stronger piezoelectric properties than bulk GaN. This phenomena may be crucial for applications of NWs and makes their study highly important. We report on an investigation of the structure evolution of a single GaN NW under an applied voltage bias along polar [0001] crystallographic direction until its mechanical break. The structural changes were investigated using coherent X-ray Bragg diffraction. The three-dimensional (3D) intensity distributions of the NWs without metal contacts, with contacts, and under applied voltage bias in opposite polar directions were analyzed. Coherent X-ray Bragg diffraction revealed the presence of significant bending of the NWs already after metal contacts deposition, which was increased at applied voltage bias. Employing analytical simulations based on elasticity theory and a finite element method (FEM) approach, we developed a 3D model of the NW bending under applied voltage. From this model and our experimental data, we determined the piezoelectric constant of the GaN NW to be about 7.7 pm/V in [0001] crystallographic direction. The ultimate tensile strength of the GaN NW was obtained to be about 1.22 GPa. Our work demonstrates the power of in operando X-ray structural studies of single NWs for their effective design and implementation with desired functional properties.

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organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
coherent X-ray Bragg diffraction, finite element method, GaN nanowires, piezoelectric effect
in
Nano Letters
volume
18
issue
9
pages
7 pages
publisher
The American Chemical Society (ACS)
external identifiers
  • scopus:85050774783
ISSN
1530-6984
DOI
10.1021/acs.nanolett.8b01802
language
English
LU publication?
yes
id
a32d5779-3358-4f2e-a91b-3eba9f017a1d
date added to LUP
2019-03-16 12:07:13
date last changed
2024-03-19 03:03:27
@article{a32d5779-3358-4f2e-a91b-3eba9f017a1d,
  abstract     = {{<p>GaN nanowires (NWs) are promising building blocks for future optoelectronic devices and nanoelectronics. They exhibit stronger piezoelectric properties than bulk GaN. This phenomena may be crucial for applications of NWs and makes their study highly important. We report on an investigation of the structure evolution of a single GaN NW under an applied voltage bias along polar [0001] crystallographic direction until its mechanical break. The structural changes were investigated using coherent X-ray Bragg diffraction. The three-dimensional (3D) intensity distributions of the NWs without metal contacts, with contacts, and under applied voltage bias in opposite polar directions were analyzed. Coherent X-ray Bragg diffraction revealed the presence of significant bending of the NWs already after metal contacts deposition, which was increased at applied voltage bias. Employing analytical simulations based on elasticity theory and a finite element method (FEM) approach, we developed a 3D model of the NW bending under applied voltage. From this model and our experimental data, we determined the piezoelectric constant of the GaN NW to be about 7.7 pm/V in [0001] crystallographic direction. The ultimate tensile strength of the GaN NW was obtained to be about 1.22 GPa. Our work demonstrates the power of in operando X-ray structural studies of single NWs for their effective design and implementation with desired functional properties.</p>}},
  author       = {{Lazarev, Sergey and Dzhigaev, Dmitry and Bi, Zhaoxia and Nowzari, Ali and Kim, Young Yong and Rose, Max and Zaluzhnyy, Ivan A. and Gorobtsov, Oleg Yu and Zozulya, Alexey V. and Lenrick, Filip and Gustafsson, Anders and Mikkelsen, Anders and Sprung, Michael and Samuelson, Lars and Vartanyants, Ivan A.}},
  issn         = {{1530-6984}},
  keywords     = {{coherent X-ray Bragg diffraction; finite element method; GaN nanowires; piezoelectric effect}},
  language     = {{eng}},
  month        = {{09}},
  number       = {{9}},
  pages        = {{5446--5452}},
  publisher    = {{The American Chemical Society (ACS)}},
  series       = {{Nano Letters}},
  title        = {{Structural Changes in a Single GaN Nanowire under Applied Voltage Bias}},
  url          = {{http://dx.doi.org/10.1021/acs.nanolett.8b01802}},
  doi          = {{10.1021/acs.nanolett.8b01802}},
  volume       = {{18}},
  year         = {{2018}},
}