1
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Ube T. Three-dimensional nanostructure analysis of non-stained Nafion in fuel-cell electrode by combined ADF-STEM tomography. Microscopy (Oxf) 2024; 73:318-328. [PMID: 38226523 PMCID: PMC11288185 DOI: 10.1093/jmicro/dfae002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/23/2023] [Accepted: 01/11/2024] [Indexed: 01/17/2024] Open
Abstract
The polymer electrolyte fuel cell (PEFC) is one of the strongest candidates for a next-generation power source for vehicles which do not emit CO2 gas as exhaust gas. The key factor in PEFCs is the nano-scaled electrochemical reactions that take place on the catalyst material and an ionomer supported by a carbon support. However, because the nano-scaled morphological features of the key materials in the catalyst compound cannot be observed clearly by transmission electron microscopy, improvement of PEFC performance had been approached by an imaginal schematic diagram based on an electrochemical analysis. In this study, we revealed the nano-scaled morphological features of the PEFC electrode in three dimensions and performed a quantitative analysis of the nanostructure by the newly developed 'Combined ADF-STEM tomography technique'. This method combines information from plural annular darkfield detectors with different electron collection angles and can emphasize the difference of the electron scattering intensity between the ionomer and carbon in the cross-sectional image of the reconstructed three-dimensional (3D) data. Therefore, this segmentation method utilizing image contrast does not require a high electron beam current like that used in energy dispersive X-ray analysis, and thus is suitable for electron beam damage-sensitive materials. By eliminating the process of manually determining the thresholds for obtaining classified component data from grayscale data, the obtained 3D structures have sufficient accuracy to allow quantitative analysis and specify the nano-scaled structural parameters directly related to power generation characteristics.
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Affiliation(s)
- Takuji Ube
- Nano-scale Characterization Center, JFE Techno-Research Corporation, Kawasaki-Ku, Kawasaki City, Kanagawa, Tokyo 2100855, Japan
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2
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Agarwal A, Kasaei L, He X, Kitichotkul R, Hitit OK, Peng M, Schultz JA, Feldman LC, Goyal VK. Shot noise-mitigated secondary electron imaging with ion count-aided microscopy. Proc Natl Acad Sci U S A 2024; 121:e2401246121. [PMID: 39052832 PMCID: PMC11295032 DOI: 10.1073/pnas.2401246121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Accepted: 07/01/2024] [Indexed: 07/27/2024] Open
Abstract
Modern science is dependent on imaging on the nanoscale, often achieved through processes that detect secondary electrons created by a highly focused incident charged particle beam. Multiple types of measurement noise limit the ultimate trade-off between the image quality and the incident particle dose, which can preclude useful imaging of dose-sensitive samples. Existing methods to improve image quality do not fundamentally mitigate the noise sources. Furthermore, barriers to assigning a physically meaningful scale make the images qualitative. Here, we introduce ion count-aided microscopy (ICAM), which is a quantitative imaging technique that uses statistically principled estimation of the secondary electron yield. With a readily implemented change in data collection, ICAM substantially reduces source shot noise. In helium ion microscopy, we demonstrate 3[Formula: see text] dose reduction and a good match between these empirical results and theoretical performance predictions. ICAM facilitates imaging of fragile samples and may make imaging with heavier particles more attractive.
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Affiliation(s)
- Akshay Agarwal
- Department of Electrical and Computer Engineering, Boston University, Boston, MA02215
| | - Leila Kasaei
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ08854
| | - Xinglin He
- Department of Electrical and Computer Engineering, Boston University, Boston, MA02215
| | | | - Oğuz Kağan Hitit
- Department of Electrical and Computer Engineering, Boston University, Boston, MA02215
| | - Minxu Peng
- Department of Electrical and Computer Engineering, Boston University, Boston, MA02215
| | | | - Leonard C. Feldman
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ08854
| | - Vivek K Goyal
- Department of Electrical and Computer Engineering, Boston University, Boston, MA02215
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3
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Peters JJP, Mullarkey T, Hedley E, Müller KH, Porter A, Mostaed A, Jones L. Electron counting detectors in scanning transmission electron microscopy via hardware signal processing. Nat Commun 2023; 14:5184. [PMID: 37626044 PMCID: PMC10457289 DOI: 10.1038/s41467-023-40875-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 08/10/2023] [Indexed: 08/27/2023] Open
Abstract
Transmission electron microscopy is a pivotal instrument in materials and biological sciences due to its ability to provide local structural and spectroscopic information on a wide range of materials. However, the electron detectors used in scanning transmission electron microscopy are often unable to provide quantified information, that is the number of electrons impacting the detector, without exhaustive calibration and processing. This results in arbitrary signal values with slow response times that cannot be used for quantification or comparison to simulations. Here we demonstrate and optimise a hardware signal processing approach to augment electron detectors to perform single electron counting.
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Affiliation(s)
- Jonathan J P Peters
- Advanced Microscopy Laboratory (AML), Trinity College Dublin, the University of Dublin, Dublin, Ireland.
- School of Physics, Trinity College Dublin, the University of Dublin, Dublin, Ireland.
| | - Tiarnan Mullarkey
- Advanced Microscopy Laboratory (AML), Trinity College Dublin, the University of Dublin, Dublin, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Dublin, Ireland
| | - Emma Hedley
- Department of Materials, University of Oxford, Oxford, UK
| | - Karin H Müller
- Faculty of Engineering, Department of Materials, Imperial College London, London, UK
| | - Alexandra Porter
- Faculty of Engineering, Department of Materials, Imperial College London, London, UK
| | - Ali Mostaed
- Department of Materials, University of Oxford, Oxford, UK
| | - Lewys Jones
- Advanced Microscopy Laboratory (AML), Trinity College Dublin, the University of Dublin, Dublin, Ireland
- School of Physics, Trinity College Dublin, the University of Dublin, Dublin, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Dublin, Ireland
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4
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Mullarkey T, Geever M, Peters JJP, Griffiths I, Nellist PD, Jones L. How Fast is Your Detector? The Effect of Temporal Response on Image Quality. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1402-1408. [PMID: 37488817 DOI: 10.1093/micmic/ozad061] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 03/08/2023] [Accepted: 05/13/2023] [Indexed: 07/26/2023]
Abstract
With increasing interest in high-speed imaging, there should be an increased interest in the response times of our scanning transmission electron microscope detectors. Previous works have highlighted and contrasted the performance of various detectors for quantitative compositional or structural studies, but here, we shift the focus to detector temporal response, and the effect this has on captured images. The rise and decay times of eight detectors' single-electron response are reported, as well as measurements of their flatness, roundness, smoothness, and ellipticity. We develop and apply a methodology for incorporating the temporal detector response into simulations, showing that a loss of resolution is apparent in both the images and their Fourier transforms. We conclude that the solid-state detector outperforms the photomultiplier tube-based detectors in all areas bar a slightly less elliptical central hole and is likely the best detector to use for the majority of applications. However, using the tools introduced here, we encourage users to effectively evaluate which detector is most suitable for their experimental needs.
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Affiliation(s)
- Tiarnan Mullarkey
- School of Physics, Trinity College Dublin, College Green, Dublin D02 PN40, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Trinity College Dublin, Dublin D02 PN40, Ireland
| | - Matthew Geever
- School of Physics, Trinity College Dublin, College Green, Dublin D02 PN40, Ireland
| | - Jonathan J P Peters
- School of Physics, Trinity College Dublin, College Green, Dublin D02 PN40, Ireland
| | - Ian Griffiths
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
| | - Peter D Nellist
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK
| | - Lewys Jones
- School of Physics, Trinity College Dublin, College Green, Dublin D02 PN40, Ireland
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin D02 PN40, Ireland
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5
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Peters JJP, Mullarkey T, Gott JA, Nelson E, Jones L. Interlacing in Atomic Resolution Scanning Transmission Electron Microscopy. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1373-1379. [PMID: 37488815 DOI: 10.1093/micmic/ozad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 03/27/2023] [Accepted: 04/24/2023] [Indexed: 07/26/2023]
Abstract
Fast frame rates are desirable in scanning transmission electron microscopy for a number of reasons: controlling electron beam dose, capturing in situ events, or reducing the appearance of scan distortions. While several strategies exist for increasing frame rates, many impact image quality or require investment in advanced scan hardware. Here, we present an interlaced imaging approach to achieve minimal loss of image quality with faster frame rates that can be implemented on many existing scan controllers. We further demonstrate that our interlacing approach provides the best possible strain precision for a given electron dose compared with other contemporary approaches.
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Affiliation(s)
- Jonathan J P Peters
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin D02 DA31, Ireland
- School of Physics, Trinity College Dublin, Dublin D02 E8C0, Ireland
| | - Tiarnan Mullarkey
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin D02 DA31, Ireland
- School of Physics, Trinity College Dublin, Dublin D02 E8C0, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Trinity College Dublin, Dublin D02 W9K7, Ireland
| | - James A Gott
- Department of Physics, University of Warwick, Coventry CV4 7AL, UK
- Advanced Materials Manufacturing Centre (AMMC), Warwick Manufacturing Group (WMG), University of Warwick, Coventry CV4 7AL, UK
| | - Elizabeth Nelson
- School of Physics, Trinity College Dublin, Dublin D02 E8C0, Ireland
| | - Lewys Jones
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Trinity College Dublin, Dublin D02 DA31, Ireland
- School of Physics, Trinity College Dublin, Dublin D02 E8C0, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Trinity College Dublin, Dublin D02 W9K7, Ireland
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6
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Agarwal A, Simonaitis J, Goyal VK, Berggren KK. Secondary electron count imaging in SEM. Ultramicroscopy 2023; 245:113662. [PMID: 36521266 DOI: 10.1016/j.ultramic.2022.113662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 11/22/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022]
Abstract
Scanning electron microscopy (SEM) is a versatile technique used to image samples at the nanoscale. Conventional imaging by this technique relies on finding the average intensity of the signal generated on a detector by secondary electrons (SEs) emitted from the sample and is subject to noise due to variations in the voltage signal from the detector. This noise can result in degradation of the SEM image quality for a given imaging dose. SE count imaging, which uses the direct count of SEs detected from the sample instead of the average signal intensity, would overcome this limitation and lead to improvement in SEM image quality. In this paper, we implement an SE count imaging scheme by synchronously outcoupling the detector and beam scan signals from the microscope and using custom code to count detected SEs. We demonstrate a ∼30% increase in the image signal-to-noise-ratio due to SE counting compared to conventional imaging. The only external hardware requirement for this imaging scheme is an oscilloscope fast enough to accurately sample the detector signal for SE counting, making the scheme easily implementable on any SEM.
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Affiliation(s)
- Akshay Agarwal
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, United States of America.
| | - John Simonaitis
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, United States of America
| | - Vivek K Goyal
- Department of Electrical and Computer Engineering, Boston University, United States of America
| | - Karl K Berggren
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, United States of America
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7
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De Wael A, De Backer A, Yu CP, Sentürk DG, Lobato I, Faes C, Van Aert S. Three Approaches for Representing the Statistical Uncertainty on Atom-Counting Results in Quantitative ADF STEM. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2022; 29:1-9. [PMID: 36117265 DOI: 10.1017/s1431927622012284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
A decade ago, a statistics-based method was introduced to count the number of atoms from annular dark-field scanning transmission electron microscopy (ADF STEM) images. In the past years, this method was successfully applied to nanocrystals of arbitrary shape, size, and composition (and its high accuracy and precision has been demonstrated). However, the counting results obtained from this statistical framework are so far presented without a visualization of the actual uncertainty about this estimate. In this paper, we present three approaches that can be used to represent counting results together with their statistical error, and discuss which approach is most suited for further use based on simulations and an experimental ADF STEM image.
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Affiliation(s)
- Annelies De Wael
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Annick De Backer
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Chu-Ping Yu
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Duygu Gizem Sentürk
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Ivan Lobato
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
| | - Christel Faes
- I-BioStat, Data Science Institute, Hasselt University, Hasselt, Belgium
| | - Sandra Van Aert
- EMAT, University of Antwerp, Antwerp, Belgium
- NANOlab Center of Excellence, University of Antwerp, Antwerp, Belgium
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8
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Image-histogram-based secondary electron counting to evaluate detective quantum efficiency in SEM. Ultramicroscopy 2021; 224:113238. [PMID: 33706085 DOI: 10.1016/j.ultramic.2021.113238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 02/10/2021] [Accepted: 02/20/2021] [Indexed: 11/21/2022]
Abstract
Scanning electron microscopy is a powerful tool for nanoscale imaging of organic and inorganic materials. An important metric for characterizing the limits of performance of these microscopes is the Detective Quantum Efficiency (DQE), which measures the fraction of emitted secondary electrons (SEs) that are detected by the SE detector. However, common techniques for measuring DQE approximate the SE emission process to be Poisson distributed, which can lead to incorrect DQE values. In this paper, we introduce a technique for measuring DQE in which we directly count the mean number of secondary electrons detected from a sample using image histograms. This technique does not assume Poisson distribution of SEs and makes it possible to accurately measure DQE for a wider range of imaging conditions. As a demonstration of our technique, we map the variation of DQE as a function of working distance in the microscope.
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9
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Mullarkey T, Downing C, Jones L. Development of a Practicable Digital Pulse Read-Out for Dark-Field STEM. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2021; 27:99-108. [PMID: 33334386 DOI: 10.1017/s1431927620024721] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
When characterizing beam-sensitive materials in the scanning transmission electron microscope (STEM), low-dose techniques are essential for the reliable observation of samples in their true state. A simple route to minimize both the total electron-dose and the dose-rate is to reduce the electron beam-current and/or raster the probe at higher speeds. At the limit of these settings, and with current detectors, the resulting images suffer from unacceptable artifacts, including signal-streaking, detector-afterglow, and poor signal-to-noise ratios (SNRs). In this article, we present an alternative approach to capture dark-field STEM images by pulse-counting individual electrons as they are scattered to the annular dark-field (ADF) detector. Digital images formed in this way are immune from analog artifacts of streaking or afterglow and allow clean, high-SNR images to be obtained even at low beam-currents. We present results from both a ThermoFisher FEI Titan G2 operated at 300 kV and a Nion UltraSTEM200 operated at 200 kV, and compare the images to conventional analog recordings. ADF data are compared with analog counterparts for each instrument, a digital detector-response scan is performed on the Titan, and the overall rastering efficiency is evaluated for various scanning parameters.
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Affiliation(s)
- Tiarnan Mullarkey
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
- Centre for Doctoral Training in the Advanced Characterisation of Materials, AMBER Centre, Dublin 2, Ireland
| | - Clive Downing
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Dublin 2, Ireland
| | - Lewys Jones
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
- Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Dublin 2, Ireland
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10
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Ponce A, Aguilar JA, Tate J, Yacamán MJ. Advances in the electron diffraction characterization of atomic clusters and nanoparticles. NANOSCALE ADVANCES 2021; 3:311-325. [PMID: 36131739 PMCID: PMC9417509 DOI: 10.1039/d0na00590h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 11/15/2020] [Indexed: 06/15/2023]
Abstract
Nanoparticles and metallic clusters continue to make a remarkable impact on novel and emerging technologies. In recent years, there have been impressive advances in the controlled synthesis of clusters and their advanced characterization. One of the most common ways to determine the structures of nanoparticles and clusters is by means of X-ray diffraction methods. However, this requires the clusters to crystallize in a similar way to those used in protein studies, which is not possible in many cases. Novel methods based on electron diffraction have been used to efficiently study individual nanoparticles and clusters and these can overcome the obstacles commonly encountered during X-ray diffraction methods without the need for large crystals. These novel methodologies have improved with advances in electron microscopy instrumentation and electron detection. Here, we review advanced methodologies for characterizing metallic nanoparticles and clusters using a variety of electron diffraction procedures. These include selected area electron diffraction, nanobeam diffraction, coherent electron diffraction, precession electron diffraction, scanning transmission electron microcopy diffraction, and high throughput data analytics, which leverage deep learning to reduce the propensity for data errors and translate nanometer and atomic scale measurements into material data.
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Affiliation(s)
- Arturo Ponce
- Department of Physics and Astronomy, The University of Texas at San Antonio San Antonio Texas 78249 USA
| | - Jeffery A Aguilar
- Idaho National Laboratory, Nuclear Science and Technology Division Idaho Falls Idaho 83415 USA
- Lockheed Martin Space, Advanced Technology Center Palo Alto California 94304 USA
| | - Jess Tate
- University of Utah, Scientific Computing Imaging Institute, Department of Electrical and Computer Engineering Salt Lake City Utah USA
| | - Miguel José Yacamán
- Department of Applied Physics and Materials Science, Center for Materials Interfaces in Research and Applications, Northern Arizona University Flagstaff AZ USA
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11
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Rachel R, Walther P, Maaßen C, Daberkow I, Matsuoka M, Witzgall R. Dual-axis STEM tomography at 200 kV: Setup, performance, limitations. J Struct Biol 2020; 211:107551. [DOI: 10.1016/j.jsb.2020.107551] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 05/14/2020] [Accepted: 06/13/2020] [Indexed: 12/18/2022]
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12
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Paterson GW, Lamb RJ, Ballabriga R, Maneuski D, O'Shea V, McGrouther D. Sub-100 nanosecond temporally resolved imaging with the Medipix3 direct electron detector. Ultramicroscopy 2019; 210:112917. [PMID: 31841837 DOI: 10.1016/j.ultramic.2019.112917] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 09/13/2019] [Accepted: 12/03/2019] [Indexed: 11/17/2022]
Abstract
Detector developments are currently enabling new capabilities in the field of transmission electron microscopy (TEM). We have investigated the limits of a hybrid pixel detector, Medipix3, to record dynamic, time varying, electron signals. Operating with an energy of 60 keV, we have utilised electrostatic deflection to oscillate electron beam position on the detector. Adopting a pump-probe imaging strategy, we have demonstrated that temporal resolutions three orders of magnitude smaller than are available for typically used TEM imaging detectors are possible. Our experiments have shown that energy deposition of the primary electrons in the hybrid pixel detector limits the overall temporal resolution. Through adjustment of user specifiable thresholds or the use of charge summing mode, we have obtained images composed from summing 10,000s frames containing single electron events to achieve temporal resolution less than 100 ns. We propose that this capability can be directly applied to studying repeatable material dynamic processes but also to implement low-dose imaging schemes in scanning transmission electron microscopy.
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Affiliation(s)
- Gary W Paterson
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
| | - Raymond J Lamb
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
| | | | - Dima Maneuski
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Val O'Shea
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Damien McGrouther
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
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13
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Song J, Allen CS, Gao S, Huang C, Sawada H, Pan X, Warner J, Wang P, Kirkland AI. Atomic Resolution Defocused Electron Ptychography at Low Dose with a Fast, Direct Electron Detector. Sci Rep 2019; 9:3919. [PMID: 30850641 PMCID: PMC6408533 DOI: 10.1038/s41598-019-40413-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/14/2019] [Indexed: 01/16/2023] Open
Abstract
Electron ptychography has recently attracted considerable interest for high resolution phase-sensitive imaging. However, to date studies have been mainly limited to radiation resistant samples as the electron dose required to record a ptychographic dataset is too high for use with beam-sensitive materials. Here we report defocused electron ptychography using a fast, direct-counting detector to reconstruct the transmission function, which is in turn related to the electrostatic potential of a two-dimensional material at atomic resolution under various low dose conditions.
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Affiliation(s)
- Jiamei Song
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Christopher S Allen
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.,Electron Physical Sciences Imaging Centre, Diamond Lightsource Ltd., Didcot, OX11 0DE, UK
| | - Si Gao
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, People's Republic of China
| | - Chen Huang
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.,Electron Physical Sciences Imaging Centre, Diamond Lightsource Ltd., Didcot, OX11 0DE, UK
| | - Hidetaka Sawada
- JEOL Ltd, 1-2 Mushashino, 3-Chome, Akishima, Tokyo, 196, Japan
| | - Xiaoqing Pan
- Department of Materials Science and Engineering, and Department of Physics and Astronomy, University of California, Irvine, CA, 92697, USA
| | - Jamie Warner
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
| | - Peng Wang
- College of Engineering and Applied Sciences, Nanjing University, Nanjing, 210093, People's Republic of China.
| | - Angus I Kirkland
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK.,Electron Physical Sciences Imaging Centre, Diamond Lightsource Ltd., Didcot, OX11 0DE, UK
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