Dislocation-Free and Atomically Flat GaN Hexagonal Microprisms for Device Applications
(2020) In Small 16(30).- Abstract
III-nitrides are considered the material of choice for light-emitting diodes (LEDs) and lasers in the visible to ultraviolet spectral range. The development is hampered by lattice and thermal mismatch between the nitride layers and the growth substrate leading to high dislocation densities. In order to overcome the issue, efforts have gone into selected area growth of nanowires (NWs), using their small footprint in the substrate to grow virtually dislocation-free material. Their geometry is defined by six tall side-facets and a pointed tip which limits the design of optoelectronic devices. Growth of dislocation-free and atomically smooth 3D hexagonal GaN micro-prisms with a flat, micrometer-sized top-surface is presented. These... (More)
III-nitrides are considered the material of choice for light-emitting diodes (LEDs) and lasers in the visible to ultraviolet spectral range. The development is hampered by lattice and thermal mismatch between the nitride layers and the growth substrate leading to high dislocation densities. In order to overcome the issue, efforts have gone into selected area growth of nanowires (NWs), using their small footprint in the substrate to grow virtually dislocation-free material. Their geometry is defined by six tall side-facets and a pointed tip which limits the design of optoelectronic devices. Growth of dislocation-free and atomically smooth 3D hexagonal GaN micro-prisms with a flat, micrometer-sized top-surface is presented. These self-forming structures are suitable for optical devices such as low-loss optical cavities for high-efficiency LEDs. The structures are made by annealing GaN NWs with a thick radial shell, reforming them into hexagonal flat-top prisms with six equivalents either m- or s-facets depending on the initial heights of the top pyramid and m-facets of the NWs. This shape is kinetically controlled and the reformation can be explained with a phenomenological model based on Wulff construction that have been developed. It is expected that the results will inspire further research into micron-sized III-nitride-based devices.
(Less)
- author
- organization
- publishing date
- 2020-07-28
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- GaN, III-nitride, microprisms, photonics, self-assembly
- in
- Small
- volume
- 16
- issue
- 30
- article number
- 1907364
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- pmid:32578387
- scopus:85087170705
- ISSN
- 1613-6810
- DOI
- 10.1002/smll.201907364
- language
- English
- LU publication?
- yes
- id
- 93206eb6-07e1-4bbc-b699-7a883fd4e0c8
- date added to LUP
- 2020-07-17 10:03:57
- date last changed
- 2024-08-22 00:41:51
@article{93206eb6-07e1-4bbc-b699-7a883fd4e0c8, abstract = {{<p>III-nitrides are considered the material of choice for light-emitting diodes (LEDs) and lasers in the visible to ultraviolet spectral range. The development is hampered by lattice and thermal mismatch between the nitride layers and the growth substrate leading to high dislocation densities. In order to overcome the issue, efforts have gone into selected area growth of nanowires (NWs), using their small footprint in the substrate to grow virtually dislocation-free material. Their geometry is defined by six tall side-facets and a pointed tip which limits the design of optoelectronic devices. Growth of dislocation-free and atomically smooth 3D hexagonal GaN micro-prisms with a flat, micrometer-sized top-surface is presented. These self-forming structures are suitable for optical devices such as low-loss optical cavities for high-efficiency LEDs. The structures are made by annealing GaN NWs with a thick radial shell, reforming them into hexagonal flat-top prisms with six equivalents either m- or s-facets depending on the initial heights of the top pyramid and m-facets of the NWs. This shape is kinetically controlled and the reformation can be explained with a phenomenological model based on Wulff construction that have been developed. It is expected that the results will inspire further research into micron-sized III-nitride-based devices.</p>}}, author = {{Khalilian, Maryam and Bi, Zhaoxia and Johansson, Jonas and Lenrick, Filip and Hultin, Olof and Colvin, Jovana and Timm, Rainer and Wallenberg, Reine and Ohlsson, Jonas and Pistol, Mats Erik and Gustafsson, Anders and Samuelson, Lars}}, issn = {{1613-6810}}, keywords = {{GaN; III-nitride; microprisms; photonics; self-assembly}}, language = {{eng}}, month = {{07}}, number = {{30}}, publisher = {{John Wiley & Sons Inc.}}, series = {{Small}}, title = {{Dislocation-Free and Atomically Flat GaN Hexagonal Microprisms for Device Applications}}, url = {{http://dx.doi.org/10.1002/smll.201907364}}, doi = {{10.1002/smll.201907364}}, volume = {{16}}, year = {{2020}}, }