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Polarized Light Microscopy and Spectroscopy of Individual Single-Walled Carbon Nanotubes

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Nano Research 2011年第8期4卷 788-794页

作者： Jacques Lefebvre paul finnie Institute for Microstructural Sciences National Research Council Ottawa Canada K IA 0R6

Polarized light microscopy （PLM） is used to image individual single-walled carbon nanotubes （SWNTs） suspended in air across a slit opening. The imaging contrast relies on the strong optical anisotropy typical of SWNTs. We combine PLM with a tunable light source to enable hyperspectral excitation spectroscopy and nanotube chirality assignment. Comparison with fluorescence microscopy and spectroscopy confirms the assignment made with PLM. This represents a versatile new approach to imaging SWNTs and related structures.

关键词： Carbon nanotube microscopy luminescence absorption polarization homodyne

The Dynamics of the Nucleation, Growth and Termination of Single-Walled Carbon Nanotubes from in situ Raman Spectroscopy During Chemical Vapor Deposition

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Nano Research 2009年第10期2卷 783-792页

作者： paul finnie Andrew Li-Pook-Than Jacques Lefebvre Institute for Microstructural Sciences National Research Council CanadaBuilding M-501200 Montreal RoadOttawaONK1A 0R6Canada Department of Physics University of Ottawa150 Louis PasteurOttawaON K1N 6N5Canada

The dynamics of the chemical vapor deposition(CVD)of single-walled carbon nanotubes(SWNTs)is extracted experimentally using in situ Raman *** are grown using a thinlm cobalt catalyst and an ethanol precursor in a miniature hot walled reactor with optical *** spectra at room temperature and at the growth temperature are compared for two growth *** evolution of the G-band,D-band,and radial breathing mode(RBM)is tracked at the growth temperature with time resolution of a few *** are three identifiable phases in the evolution of the Raman signal intensity:an initial exponential increasing phase,a linear growth phase,and a saturation *** situ optical spectroscopy thus enables the study of nucleation,steady growth,and deactivation processes to be investigated separately in real *** evolution curves for all bands(G,D,and RBM),when scaled,collapse onto the same curve,to within experimental uncertainty.

关键词： Single-walled carbon nanotube chemical vapor deposition Raman spectroscopy nucleation termination

Raman microscopy mapping for the purity assessment of chirality enriched carbon nanotube networks in thin- film transistors

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Nano Research 2015年第7期8卷 2179-2187页

作者： Zhao Li Jianfu Ding paul finnie Jacques Lefebvre Fuyong Cheng ChristopherT. Kingston Patrick R. L. Malenfant Security and Disruptive Technologies Portfolio National Research Council Canada 1200 Montreal Road Ottawa Ontario K1A OR6 Canada

With recent improvements in carbon nanotube separation methods, the accurate determination of residual metallic carbon nanotubes in a purified nanotube sample is important, particularly for those interested in using semiconducting single-walled carbon nanotubes （SWCNTs） in electronic device applications such as thin-film transistors （TFTs）. This work demonstrates that Raman microscopy mapping is a powerful characterization tool for quantifying residual metallic carbon nanotubes present in highly enriched semiconducting nanotube networks. Raman mapping correlates well with absorption spectroscopy, yet it provides greater differentiation in purity. Electrical data from TFTs with channel lengths of 2.5 and 5μ m demonstrate the utility of the method. By comparing samples with nominal purities of 99.0% and 99.8%, a clear differentiation can be made when evaluating the current on/off ratio as a function of channel length, and thus the Raman mapping method provides a means to guide device fabrication by correlating SWCNT network density and purity with TFT channel scaling.

关键词： raman spectroscopy carbon nanotubes thin film transistors microscopy mapping purity assessment

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多功能、可持续且广泛兼容的测试解决方案

电子技术应用 2013年第3期39卷 12-13页

作者： paul Pankratz David finnie CACA国际公司

“CACI非常信赖NI的产品质量，并与之建立了密切的合作关系，因而选择了NI的多款仪器作为CBATS测试系统的核心。CACI与NI相互信赖，共同合作开发价格合理的高质量可持续测试解决方案。”

关键词：测试解决方案航空电子设备武器系统多功能兼容产品质量合作关系测试系统