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In situ analysis of catalyst composition during gold catalyzed GaAs nanowire growth.

ABSTRACT: Semiconductor nanowires offer the opportunity to incorporate novel structures and functionality into electronic and optoelectronic devices. A clear understanding of the nanowire growth mechanism is essential for well-controlled growth of structures with desired properties, but the understanding is currently limited by a lack of empirical measurements of important parameters during growth, such as catalyst particle composition. However, this is difficult to accurately determine by investigating post-growth. We report direct in situ measurement of the catalyst composition during nanowire growth for the first time. We study Au-seeded GaAs nanowires inside an electron microscope as they grow and measure the catalyst composition using X-ray energy dispersive spectroscopy. The Ga content in the catalyst during growth increases with both temperature and Ga precursor flux.

SUBMITTER: Maliakkal CB

PROVIDER: S-EPMC6783420 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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In situ analysis of catalyst composition during gold catalyzed GaAs nanowire growth.

Maliakkal Carina B CB Jacobsson Daniel D Tornberg Marcus M Persson Axel R AR Johansson Jonas J Wallenberg Reine R Dick Kimberly A KA

Nature communications 20191008 1

Semiconductor nanowires offer the opportunity to incorporate novel structures and functionality into electronic and optoelectronic devices. A clear understanding of the nanowire growth mechanism is essential for well-controlled growth of structures with desired properties, but the understanding is currently limited by a lack of empirical measurements of important parameters during growth, such as catalyst particle composition. However, this is difficult to accurately determine by investigating p ...[more]

PMID: 31594930

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