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Toyama S, Seki T, Anada S, Sasaki H, Yamamoto K, Ikuhara Y, Shibata N. Quantitative electric field mapping of a p-n junction by DPC STEM. Ultramicroscopy 2020; 216:113033. [PMID: 32570133 DOI: 10.1016/j.ultramic.2020.113033] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/09/2020] [Accepted: 05/24/2020] [Indexed: 10/24/2022]
Abstract
Local electromagnetic fields in a specimen is measured at high spatial resolutions using differential phase contrast (DPC) imaging in scanning transmission electron microscopy (STEM). According to previous studies, DPC signals can be quantified by measuring the center of mass of the diffraction pattern intensity and/or performing a deconvolution method based on a phase contrast transfer function (PCTF). However, when using a segmented detector, the field strength has been considerably underestimated for a very thick specimen. The main cause of the underestimation is assumed to be inelastic scattering, mainly bulk plasmon scattering. In this study, we develop a method to remove this inelastic scattering effect from segmented detector DPC signals by modifying the PCTF deconvolution method. Field quantification results using this new technique are compared with those using pixelated detector DPC and electron holography, and all results indicated good agreement within an error margin.
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Affiliation(s)
- Satoko Toyama
- Institute of Engineering Innovation, School of Engineering, University of Tokyo, Tokyo 113-8656, Japan
| | - Takehito Seki
- Institute of Engineering Innovation, School of Engineering, University of Tokyo, Tokyo 113-8656, Japan
| | - Satoshi Anada
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan
| | - Hirokazu Sasaki
- Advanced Technologies R&D Laboratories, Furukawa Electric Co., Ltd., Yokohama 220-0073, Japan
| | - Kazuo Yamamoto
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan
| | - Yuichi Ikuhara
- Institute of Engineering Innovation, School of Engineering, University of Tokyo, Tokyo 113-8656, Japan; Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan
| | - Naoya Shibata
- Institute of Engineering Innovation, School of Engineering, University of Tokyo, Tokyo 113-8656, Japan; Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan.
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2
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Cordoba C, Zeng X, Wolf D, Lubk A, Barrigón E, Borgström MT, Kavanagh KL. Three-Dimensional Imaging of Beam-Induced Biasing of InP/GaInP Tunnel Diodes. NANO LETTERS 2019; 19:3490-3497. [PMID: 31072098 DOI: 10.1021/acs.nanolett.9b00249] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Electron holographic tomography was used to obtain three-dimensional reconstructions of the morphology and electrostatic potential gradient of axial GaInP/InP nanowire tunnel diodes. Crystal growth was carried out in two opposite directions: GaInP-Zn/InP-S and InP-Sn/GaInP-Zn, using Zn as the p-type dopant in the GaInP but with changes to the n-type dopant (S or Sn) in the InP. Secondary electron and electron beam-induced current images obtained using scanning electron microscopy indicated the presence of p-n junctions in both cases and current-voltage characteristics measured via lithographic contacts showed the negative differential resistance, characteristic of band-to-band tunneling, for both diodes. Electron holographic tomography measurements confirmed a short depletion width in both cases (21 ± 3 nm) but different built-in potentials, Vbi, of 1.0 V for the p-type (Zn) to n-type (S) transition, and 0.4 V for both were lower than the expected 1.5 V for these junctions if degenerately doped. Charging induced by the electron beam was evident in phase images which showed nonlinearity in the surrounding vacuum, most severe in the case of the nanowire grounded at the p-type Au contact. We attribute their lower Vbi to asymmetric secondary electron emission, beam-induced current biasing, and poor grounding contacts.
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Affiliation(s)
- Cristina Cordoba
- Department of Physics , Simon Fraser University , 8888 University Drive, Burnaby , British Columbia V5A 1S6 , Canada
| | - Xulu Zeng
- Division of Solid State Physics and NanoLund , P.O. Box 118, SE-221 00 Lund , Sweden
| | - Daniel Wolf
- Institute for Solid State Research , Helmholtzstrasse 20 , D-01069 Dresden , Germany
| | - Axel Lubk
- Institute for Solid State Research , Helmholtzstrasse 20 , D-01069 Dresden , Germany
| | - Enrique Barrigón
- Division of Solid State Physics and NanoLund , P.O. Box 118, SE-221 00 Lund , Sweden
| | - Magnus T Borgström
- Division of Solid State Physics and NanoLund , P.O. Box 118, SE-221 00 Lund , Sweden
| | - Karen L Kavanagh
- Department of Physics , Simon Fraser University , 8888 University Drive, Burnaby , British Columbia V5A 1S6 , Canada
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3
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McCartney MR, Dunin-Borkowski RE, Smith DJ. Quantitative measurement of nanoscale electrostatic potentials and charges using off-axis electron holography: Developments and opportunities. Ultramicroscopy 2019; 203:105-118. [PMID: 30772077 DOI: 10.1016/j.ultramic.2019.01.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 12/27/2018] [Accepted: 01/21/2019] [Indexed: 12/01/2022]
Abstract
Off-axis electron holography has evolved into a powerful electron-microscopy-based technique for characterizing electromagnetic fields with nanometer-scale resolution. In this paper, we present a review of the application of off-axis electron holography to the quantitative measurement of electrostatic potentials and charge density distributions. We begin with a short overview of the theoretical and experimental basis of the technique. Practical aspects of phase imaging, sample preparation and microscope operation are outlined briefly. Applications of off-axis electron holography to a wide range of materials are then described in more detail. Finally, challenges and future opportunities for electron holography investigations of electrostatic fields and charge density distributions are presented.
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Affiliation(s)
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - David J Smith
- Department of Physics, Arizona State University, Tempe, AZ 85287, USA
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4
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Wang LM, Qdemat A, Petracic O, Kentzinger E, Rücker U, Zheng F, Lu PH, Wei XK, Dunin-Borkowski RE, Brückel T. Manipulation of dipolar magnetism in low-dimensional iron oxide nanoparticle assemblies. Phys Chem Chem Phys 2019; 21:6171-6177. [DOI: 10.1039/c9cp00302a] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Trench-patterned iron oxide nanoparticles are switched between a superspin glass and a superferromagnetic state.
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Affiliation(s)
- Li-Ming Wang
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
- Institute of High Energy Physics
| | - Asma Qdemat
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
| | - Oleg Petracic
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
| | - Emmanuel Kentzinger
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
| | - Ulrich Rücker
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
| | - Fengshan Zheng
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | - Peng-Han Lu
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | - Xian-Kui Wei
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | - Rafal E. Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute
- Forschungszentrum Jülich GmbH
- 52425 Jülich
- Germany
| | - Thomas Brückel
- Jülich Centre for Neutron Science JCNS and Peter Grüberg Institut PGI
- JARA-FIT
- Jülich
- Germany
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5
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Measuring nanometre-scale electric fields in scanning transmission electron microscopy using segmented detectors. Ultramicroscopy 2017; 182:169-178. [DOI: 10.1016/j.ultramic.2017.07.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 06/28/2017] [Accepted: 07/02/2017] [Indexed: 11/18/2022]
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6
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Tavabi AH, Arai S, Muto S, Tanji T, Dunin-Borkowski RE. In situ transmission electron microscopy of ionic conductivity and reaction mechanisms in ultrathin solid oxide fuel cells. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2014; 20:1817-1825. [PMID: 25382667 DOI: 10.1017/s143192761401349x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Solid oxide fuel cells (SOFCs) are promising candidates for use in alternative energy technologies. A full understanding of the reaction mechanisms in these dynamic material systems is required to optimize device performance and overcome present limitations. Here, we show that in situ transmission electron microscopy (TEM) can be used to study redox reactions and ionic conductivity in SOFCs in a gas environment at elevated temperature. We examine model ultrathin half and complete cells in two environmental TEMs using off-axis electron holography and electron energy-loss spectroscopy. Our results from the model cells provide insight into the essential phenomena that are important for the operation of commercial devices. Changes in the activities of dopant cations in the solid electrolyte are detected during oxygen anion conduction, demonstrating the key role of dopants in electrolyte architecture in SOFCs.
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Affiliation(s)
- Amir H Tavabi
- 1Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute,Forschungszentrum Jülich,52425 Jülich,Germany
| | - Shigeo Arai
- 2EcoTopia Science Institute,Nagoya University,Furo-cho,Chikusa,Nagoya 464-8603,Japan
| | - Shunsuke Muto
- 2EcoTopia Science Institute,Nagoya University,Furo-cho,Chikusa,Nagoya 464-8603,Japan
| | - Takayoshi Tanji
- 2EcoTopia Science Institute,Nagoya University,Furo-cho,Chikusa,Nagoya 464-8603,Japan
| | - Rafal E Dunin-Borkowski
- 1Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute,Forschungszentrum Jülich,52425 Jülich,Germany
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7
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Duchamp M, Xu Q, Dunin-Borkowski RE. Convenient preparation of high-quality specimens for annealing experiments in the transmission electron microscope. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2014; 20:1638-1645. [PMID: 25372115 DOI: 10.1017/s1431927614013476] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A procedure based on focused ion beam milling and in situ lift-out is introduced for the preparation of high-quality specimens for in situ annealing experiments in the transmission electron microscope. The procedure allows an electron-transparent lamella to be cleaned directly on a heating chip using a low ion energy and back-side milling in order to minimize redeposition and damage. The approach is illustrated through the preparation of an Al-Mn-Fe complex metallic alloy specimen.
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Affiliation(s)
- Martial Duchamp
- 1Ernst Ruska-Center for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute,Forschungszentrum Jülich,52428 Jülich,Germany
| | - Qiang Xu
- 2DENSsolutions,2628XH Delft,The Netherlands
| | - Rafal E Dunin-Borkowski
- 1Ernst Ruska-Center for Microscopy and Spectroscopy with Electrons (ER-C) and Peter Grünberg Institute,Forschungszentrum Jülich,52428 Jülich,Germany
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8
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Xiong X, Weyland M. Microstructural characterization of an Al-li-mg-cu alloy by correlative electron tomography and atom probe tomography. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2014; 20:1022-1028. [PMID: 24815550 DOI: 10.1017/s1431927614000798] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Correlative electron tomography and atom probe tomography have been carried out successfully on the same region of a commercial 8090 aluminum alloy (Al-Li-Mg-Cu). The combination of the two techniques allows accurate geometric reconstruction of the atom probe tomography data verified by crystallographic information retrieved from the reconstruction. Quantitative analysis of the precipitate phase compositions and volume fractions of each phase have been obtained from the atom probe tomography and electron tomography at various scales, showing strong agreement between both techniques.
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Affiliation(s)
- Xiangyuan Xiong
- 1Monash Centre for Electron Microscopy,Monash University,VIC 3800,Australia
| | - Matthew Weyland
- 1Monash Centre for Electron Microscopy,Monash University,VIC 3800,Australia
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9
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Pantzer A, Vakahy A, Eliyahou Z, Levi G, Horvitz D, Kohn A. Dopant mapping in thin FIB prepared silicon samples by Off-Axis Electron Holography. Ultramicroscopy 2014; 138:36-45. [DOI: 10.1016/j.ultramic.2013.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 12/05/2013] [Accepted: 12/13/2013] [Indexed: 10/25/2022]
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10
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Somodi P, Twitchett-Harrison A, Midgley P, Kardynał B, Barnes C, Dunin-Borkowski R. Finite element simulations of electrostatic dopant potentials in thin semiconductor specimens for electron holography. Ultramicroscopy 2013; 134:160-6. [DOI: 10.1016/j.ultramic.2013.06.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 06/29/2013] [Accepted: 06/29/2013] [Indexed: 11/28/2022]
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11
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McCartney MR, Agarwal N, Chung S, Cullen DA, Han MG, He K, Li L, Wang H, Zhou L, Smith DJ. Quantitative phase imaging of nanoscale electrostatic and magnetic fields using off-axis electron holography. Ultramicroscopy 2010. [DOI: 10.1016/j.ultramic.2010.01.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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12
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Towards automated electron holographic tomography for 3D mapping of electrostatic potentials. Ultramicroscopy 2010; 110:390-9. [DOI: 10.1016/j.ultramic.2009.12.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2009] [Revised: 12/21/2009] [Accepted: 12/22/2009] [Indexed: 11/22/2022]
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13
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The effect of dynamical scattering in off-axis holographic mean inner potential and inelastic mean free path measurements. Ultramicroscopy 2010. [DOI: 10.1016/j.ultramic.2009.09.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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14
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COOPER D, TRUCHE R, TWITCHETT-HARRISON A, DUNIN-BORKOWSKI R, MIDGLEY P. Quantitative off-axis electron holography of GaAsp-njunctions prepared by focused ion beam milling. J Microsc 2009; 233:102-13. [DOI: 10.1111/j.1365-2818.2008.03101.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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15
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Cooper D, Truche R, Rouviere JL. Reduction of electrical damage in specimens prepared using focused ion beam milling for dopant profiling using off-axis electron holography. Ultramicroscopy 2008; 108:488-93. [PMID: 17888576 DOI: 10.1016/j.ultramic.2007.08.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2006] [Revised: 07/12/2007] [Accepted: 08/01/2007] [Indexed: 11/26/2022]
Abstract
GaAs specimens containing p-n junctions have been prepared using focused ion beam (FIB) milling for examination using off-axis electron holography. By lowering the FIB operating voltage from 30 to 8 kV, we have shown a systematic reduction of the electrically 'inactive' thickness from 220 to 100 nm, resulting in a significant increase in the step in phase measured across the junctions as well as an improvement in the signal-to-noise ratio. We also show that the step in phase measured across the junctions can be influenced by the intensity of the electron beam.
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Dunin–Borkowski R, Kasama T, Harrison R. Electron Holography of Nanostructured Materials. NANOCHARACTERISATION 2007. [DOI: 10.1039/9781847557926-00138] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- R.E. Dunin–Borkowski
- Department of Materials Science and Metallurgy, University of Cambridge Pembroke Street Cambridge CB2 3QZ UK
- Center for Electron Nanoscopy, Technical University of Denmark DK-2800 Kongens Lyngby Denmark
| | - T. Kasama
- Frontier Research System The Institute of Physical and Chemical Research Hatoyama Saitama 350–0395 Japan
- Department of Materials Science and Metallurgy, University of Cambridge Pembroke Street Cambridge CB2 3QZ UK
| | - R.J. Harrison
- Department of Earth Sciences, University of Cambridge Downing Street Cambridge CB2 3EQ UK
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Midgley PA, Ward EPW, Hungría AB, Thomas JM. Nanotomography in the chemical, biological and materials sciences. Chem Soc Rev 2007; 36:1477-94. [PMID: 17660880 DOI: 10.1039/b701569k] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nanotomography is a technique of growing importance in the investigation of the shape, size, distribution and elemental composition of a wide variety of materials that are of central interest to investigators in the physical and biological sciences. Nanospatial factors often hold the key to a deeper understanding of the properties of matter at the nanoscale level. With recent advances in tomography, it is possible to achieve experimental resolution in the nanometre range, and to determine with elemental specificity the three-dimensional distribution of materials. This critical review deals principally with electron tomography, but it also outlines the power and future potential of transmission X-ray tomography, and alludes to other related techniques.
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Affiliation(s)
- Paul A Midgley
- Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, UK CB2 3QZ.
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