Direct Observations of Twin Formation Dynamics in Binary Semiconductors
Autor: | Christopher R. Andersen, Robin Sjökvist, Kimberly A. Dick, Krishna Kumar, Carina B. Maliakkal, Marcus Tornberg, Daniel Jacobsson |
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Rok vydání: | 2021 |
Předmět: |
Stacking-Faults
Materials science Environmental Transmission Electron Microscopy Nanowires business.industry Materials Science (miscellaneous) GaAs Dynamics (mechanics) Binary number In Situ TEM Deterministic Crystal Growth Semiconductor Chemistry (miscellaneous) Chemical physics MOCVD Twinplane business |
Zdroj: | Tornberg, M, Sjökvist, R, Kumar, K, Andersen, C R, Maliakkal, C B, Jacobsson, D & Dick, K A 2022, ' Direct Observations of Twin Formation Dynamics in Binary Semiconductors ', ACS Nanoscience Au, vol. 2, no. 1, pp. 49–56 . https://doi.org/10.1021/acsnanoscienceau.1c00021 |
ISSN: | 2694-2496 |
DOI: | 10.1021/acsnanoscienceau.1c00021 |
Popis: | With the increased demand for controlled deterministic growth of III–V semiconductors at the nanoscale, the impact and interest of understanding defect formation and crystal structure switching becomes increasingly important. Vapor–liquid–solid (VLS) growth of semiconductor nanocrystals is an important mechanism for controlling and studying the formation of individual crystal layers and stacking defects. Using in situ studies, combining atomic resolution of transmission electron microscopy and controlled VLS crystal growth using metal organic chemical vapor deposition, we investigate the simplest achievable change in atomic layer stacking–single twinned layers formed in GaAs. Using Au-assisted GaAs nanowires of various diameters, we study the formation of individual layers with atomic resolution to reveal the growth difference in forming a twin defect. We determine that the formation of a twinned layer occurs significantly more slowly than that of a normal crystal layer. To understand this, we conduct thermodynamic modeling and determine that the propagation of a twin is limited by the energy cost of forming the twin interface. Finally, we determine that the slower propagation of twinned layers increases the probability of additional layers nucleating, such that multiple layers grow simultaneously. This observation challenges the current understanding that continuous uniform epitaxial growth, especially in the case of liquid-metal assisted nanowires, proceeds one single layer at a time and that its progression is limited by the nucleation rate. |
Databáze: | OpenAIRE |
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