151
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Liu J, Allard LF. Surface channeling in aberration-corrected scanning transmission electron microscopy of nanostructures. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2010; 16:425-433. [PMID: 20598201 DOI: 10.1017/s1431927610000450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The aberration-corrected scanning transmission electron microscope can provide information on nanostructures with sub-Angström image resolution. The relatively intuitive interpretation of high-angle annular dark-field (HAADF) imaging technique makes it a popular tool to image a variety of samples and finds broad applications to characterizing nanostructures, especially when combined with electron energy-loss spectroscopy and X-ray energy-dispersive spectroscopy techniques. To quantitatively interpret HAADF images, however, requires full understanding of the various types of signals that contribute to the HAADF image contrast. We have observed significant intensity enhancement in HAADF images, and large expansion of lattice spacings, of surface atoms of atomically flat ZnO surfaces. The surface-resonance channeling effect, one of the electron-beam channeling phenomena in crystalline nanostructures, was invoked to explain the observed image intensity enhancement. A better understanding of the effect of electron beam channeling along surfaces or interfaces on HAADF image contrast may have implications for quantifying HAADF images and may provide new routes to utilize the channeling phenomenon to study surface structures with sub-Angström spatial resolution.
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Affiliation(s)
- Jingyue Liu
- Department of Physics and Astronomy, University of Missouri-St Louis, One University Boulevard, Center for Nanoscience, St Louis, MO 63121, USA.
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152
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Ortalan V, Uzun A, Gates BC, Browning ND. Direct imaging of single metal atoms and clusters in the pores of dealuminated HY zeolite. NATURE NANOTECHNOLOGY 2010; 5:506-10. [PMID: 20495553 DOI: 10.1038/nnano.2010.92] [Citation(s) in RCA: 102] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 04/09/2010] [Indexed: 05/21/2023]
Abstract
Zeolites are aluminosilicate materials that contain regular three-dimensional arrays of molecular-scale pores, and they can act as hosts for catalytically active metal clusters. The catalytic properties of such zeolites depend on the sizes and shapes of the clusters, and also on the location of the clusters within the pores. Transmission electron microscopy has been used to image single atoms and nanoclusters on surfaces, but the damage caused by the electron beam has made it difficult to image zeolites. Here, we show that aberration-corrected scanning transmission electron microscopy can be used to determine the locations of individual metal atoms and nanoclusters within the pores of a zeolite. We imaged the active sites of iridium catalysts anchored in dealuminated HY zeolite crystals, determined their locations and approximate distance from the crystal surface, and deduced a possible cluster formation mechanism.
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Affiliation(s)
- Volkan Ortalan
- Department of Chemical Engineering and Materials Science, University of California-Davis, One Shields Avenue, Davis, California 95616, USA.
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153
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Wang P, Behan G, Takeguchi M, Hashimoto A, Mitsuishi K, Shimojo M, Kirkland AI, Nellist PD. Nanoscale energy-filtered scanning confocal electron microscopy using a double-aberration-corrected transmission electron microscope. PHYSICAL REVIEW LETTERS 2010; 104:200801. [PMID: 20867018 DOI: 10.1103/physrevlett.104.200801] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2009] [Indexed: 05/08/2023]
Abstract
We demonstrate that a transmission electron microscope fitted with two spherical-aberration correctors can be operated as an energy-filtered scanning confocal electron microscope. A method for establishing this mode is described and initial results showing 3D chemical mapping with nanoscale sensitivity to height and thickness changes in a carbon film are presented. Importantly, uncorrected chromatic aberration does not limit the depth resolution of this technique and moreover performs an energy-filtering role, which is explained in terms of a combined depth and energy-loss response function.
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Affiliation(s)
- Peng Wang
- Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United Kingdom
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154
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García de Abajo FJ, Asenjo-Garcia A, Kociak M. Multiphoton absorption and emission by interaction of swift electrons with evanescent light fields. NANO LETTERS 2010; 10:1859-1863. [PMID: 20415459 DOI: 10.1021/nl100613s] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We introduce a theory to describe the interaction of swift electrons with strong evanescent light fields. This allows us to explain recent experimental results of multiple energy losses and gains for electrons passing near illuminated nanostructures. A complex evolution of the electron state over attosecond time scales is unveiled, giving rise to non-Poissonian distributions of multiphoton features in the electron spectra. Prospects for application to nanoscale-resolved transmission electron microscopy and spectroscopy are discussed.
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155
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De Caro L, Carlino E, Caputo G, Cozzoli PD, Giannini C. Electron diffractive imaging of oxygen atoms in nanocrystals at sub-ångström resolution. NATURE NANOTECHNOLOGY 2010; 5:360-365. [PMID: 20364132 DOI: 10.1038/nnano.2010.55] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2009] [Accepted: 03/01/2010] [Indexed: 05/29/2023]
Abstract
High-resolution imaging of low-atomic-number chemical elements using electron microscopy is challenging and may require the use of high doses of electrons. Electron diffractive imaging, which creates real-space images using diffraction intensities and phase retrieval methods, could overcome such issues, although it is also subject to limitations. Here, we show that a combination of electron diffractive imaging and high-resolution transmission electron microscopy can image individual TiO(2) nanocrystals with a resolution of 70 pm while exposing the specimen to a low dose of electrons. Our approach, which does not require spherical and chromatic aberration correction, can reveal the location of light atoms (oxygen) in the crystal lattice. We find that the unit cell in nanoscale TiO(2) is subtly different to that in the corresponding bulk.
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Affiliation(s)
- Liberato De Caro
- Istituto di Cristallografia (IC-CNR) via Amendola 122/O, Bari, Italy
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156
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Lupini AR, Wang P, Nellist PD, Kirkland AI, Pennycook SJ. Aberration measurement using the Ronchigram contrast transfer function. Ultramicroscopy 2010; 110:891-8. [PMID: 20434843 DOI: 10.1016/j.ultramic.2010.04.006] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2009] [Revised: 03/28/2010] [Accepted: 04/13/2010] [Indexed: 11/26/2022]
Abstract
The bright field contrast transfer function is one of the most useful concepts in conventional transmission electron microscopy. However, the electron Ronchigram contrast transfer function, as derived by Cowley, is inherently more complicated since it is not isoplanatic. Here, we derive a local contrast transfer function for small patches in a Ronchigram and demonstrate its utility for the direct measurement of aberrations from single Ronchigrams of an amorphous film. We describe the measurement of aberrations from both simulated and experimental images and elucidate the effects due to higher-order aberrations, separating those arising from the pre- and post-sample optics, and partial coherence.
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Affiliation(s)
- A R Lupini
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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157
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Zewail AH. Micrographia of the twenty-first century: from camera obscura to 4D microscopy. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2010; 368:1191-204. [PMID: 20123754 PMCID: PMC3263811 DOI: 10.1098/rsta.2009.0265] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this paper, the evolutionary and revolutionary developments of microscopic imaging are overviewed with a perspective on origins. From Alhazen's camera obscura, to Hooke and van Leeuwenhoek's two-dimensional optical micrography, and on to three- and four-dimensional (4D) electron microscopy, these developments over a millennium have transformed humans' scope of visualization. The changes in the length and time scales involved are unimaginable, beginning with the visible shadows of candles at the centimetre and second scales, and ending with invisible atoms with space and time dimensions of sub-nanometre and femtosecond. With these advances it has become possible to determine the structures of matter and to observe their elementary dynamics as they unfold in real time. Such observations provide the means for visualizing materials behaviour and biological function, with the aim of understanding emergent phenomena in complex systems.
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Affiliation(s)
- Ahmed H Zewail
- Physical Biology Center for Ultrafast Science and Technology, Arthur Amos Noyes Laboratory of Chemical Physics, California Institute of Technology, Pasadena, CA 91125, USA.
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158
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de Jonge N, Bigelow WC, Veith GM. Atmospheric pressure scanning transmission electron microscopy. NANO LETTERS 2010; 10:1028-31. [PMID: 20146428 DOI: 10.1021/nl904254g] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Scanning transmission electron microscope (STEM) images of gold nanoparticles at atmospheric pressure have been recorded through a 0.36 mm thick mixture of CO, O2, and He. This was accomplished using a reaction cell consisting of two electron-transparent silicon nitride membranes. Gold nanoparticles of a full width at half-maximum diameter of 1.0 nm were visible above the background noise, and the achieved edge resolution was 0.4 nm in accordance with calculations of the beam broadening.
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Affiliation(s)
- Niels de Jonge
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
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159
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Vallet-Regí M, Manzano M, González-Calbet JM, Okunishi E. Evidence of drug confinement into silica mesoporous matrices by STEM spherical aberration corrected microscopy. Chem Commun (Camb) 2010; 46:2956-8. [PMID: 20386835 DOI: 10.1039/c000806k] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
For the first time it has been possible to detect drug molecules confined into the inner part of pore channels of ordered mesoporous materials. This has been possible using spherical aberration correctors incorporated to a STEM microscope, which allows illuminating an individual atom with the electron beam to identify an unknown substance.
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Affiliation(s)
- María Vallet-Regí
- Departamento de Química Inorgánica y Bioinorgánica, Facultad de Farmacia, Universidad Complutense de Madrid, 28040, Spain.
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160
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Veith G, Lupini A, Pennycook S, Dudney N. Influence of Support Hydroxides on the Catalytic Activity of Oxidized Gold Clusters. ChemCatChem 2010. [DOI: 10.1002/cctc.200900243] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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161
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Carlino E. Quantitative Z-contrast atomic resolution studies of semiconductor nanostructured materials. ACTA ACUST UNITED AC 2010. [DOI: 10.1088/1742-6596/209/1/012005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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162
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Scanning moiré fringe imaging by scanning transmission electron microscopy. Ultramicroscopy 2010; 110:229-33. [DOI: 10.1016/j.ultramic.2009.11.015] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 11/10/2009] [Accepted: 11/18/2009] [Indexed: 11/18/2022]
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163
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de Jonge N, Sougrat R, Northan BM, Pennycook SJ. Three-dimensional scanning transmission electron microscopy of biological specimens. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2010; 16:54-63. [PMID: 20082729 PMCID: PMC2917646 DOI: 10.1017/s1431927609991280] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
A three-dimensional (3D) reconstruction of the cytoskeleton and a clathrin-coated pit in mammalian cells has been achieved from a focal-series of images recorded in an aberration-corrected scanning transmission electron microscope (STEM). The specimen was a metallic replica of the biological structure comprising Pt nanoparticles 2-3 nm in diameter, with a high stability under electron beam radiation. The 3D dataset was processed by an automated deconvolution procedure. The lateral resolution was 1.1 nm, set by pixel size. Particles differing by only 10 nm in vertical position were identified as separate objects with greater than 20% dip in contrast between them. We refer to this value as the axial resolution of the deconvolution or reconstruction, the ability to recognize two objects, which were unresolved in the original dataset. The resolution of the reconstruction is comparable to that achieved by tilt-series transmission electron microscopy. However, the focal-series method does not require mechanical tilting and is therefore much faster. 3D STEM images were also recorded of the Golgi ribbon in conventional thin sections containing 3T3 cells with a comparable axial resolution in the deconvolved dataset.
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Affiliation(s)
- Niels de Jonge
- Vanderbilt University Medical Center, Department of Molecular Physiology and Biophysics, Light Hall 702, Nashville, TN 37232-0615, USA.
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164
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Kalinin SV, Rodriguez BJ, Borisevich AY, Baddorf AP, Balke N, Chang HJ, Chen LQ, Choudhury S, Jesse S, Maksymovych P, Nikiforov MP, Pennycook SJ. Defect-mediated polarization switching in ferroelectrics and related materials: from mesoscopic mechanisms to atomistic control. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:314-22. [PMID: 20217712 DOI: 10.1002/adma.200900813] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The plethora of lattice and electronic behaviors in ferroelectric and multiferroic materials and heterostructures opens vistas into novel physical phenomena including magnetoelectric coupling and ferroelectric tunneling. The development of new classes of electronic, energy-storage, and information-technology devices depends critically on understanding and controlling field-induced polarization switching. Polarization reversal is controlled by defects that determine activation energy, critical switching bias, and the selection between thermodynamically equivalent polarization states in multiaxial ferroelectrics. Understanding and controlling defect functionality in ferroelectric materials is as critical to the future of oxide electronics and solid-state electrochemistry as defects in semiconductors are for semiconductor electronics. Here, recent advances in understanding the defect-mediated switching mechanisms, enabled by recent advances in electron and scanning probe microscopy, are discussed. The synergy between local probes and structural methods offers a pathway to decipher deterministic polarization switching mechanisms on the level of a single atomically defined defect.
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165
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Rabier J, Pizzagalli L, Demenet J. Chapter 93 Dislocations in Silicon at High Stress. DISLOCATIONS IN SOLIDS 2010. [DOI: 10.1016/s1572-4859(09)01602-7] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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166
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Villa A, Wang D, Su D, Veith GM, Prati L. Using supported Au nanoparticles as starting material for preparing uniform Au/Pd bimetallic catalysts. Phys Chem Chem Phys 2010; 12:2183-9. [DOI: 10.1039/b919322g] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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167
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Nicolosi V, Aslam Z, Sader K, Hughes GM, Vengust D, Young NP, Doole R, Mihailovic D, Bleloch AL, Kirkland AI, Grobert N, Nellist PD. A facile route to self-assembled Hg//MoSI nanowire networks. NEW J CHEM 2010. [DOI: 10.1039/c0nj00237b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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168
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Wang Z, Saito M, Tsukimoto S, Ikuhara Y. Interface atomic-scale structure and its impact on quantum electron transport. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2009; 21:4966-4969. [PMID: 25376400 DOI: 10.1002/adma.200900877] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 05/04/2009] [Indexed: 06/04/2023]
Abstract
Local structure, chemistry, and bonding at interfaces often radically affect the properties of materials. A combination of scanning transmission electron microscopy and density functional theory calculations reveals an atomic layer of carbon at a SiC/Ti3 SiC2 interface in Ohmic contact to p-type SiC, which results in stronger adhesion, a lowered Schottky barrier, and enhanced transport. This is a key factor to understanding the origin of the Ohmic nature.
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Affiliation(s)
- Zhongchang Wang
- WPI Research Center Advanced Institute for Materials Research, Tohoku University 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)
| | - Mitsuhiro Saito
- WPI Research Center Advanced Institute for Materials Research, Tohoku University 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)
| | - Susumu Tsukimoto
- WPI Research Center Advanced Institute for Materials Research, Tohoku University 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)
| | - Yuichi Ikuhara
- WPI Research Center Advanced Institute for Materials Research, Tohoku University 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)
- Institute of Engineering Innovation The University of Tokyo 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656 (Japan)
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169
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Sawada H, Tanishiro Y, Ohashi N, Tomita T, Hosokawa F, Kaneyama T, Kondo Y, Takayanagi K. STEM imaging of 47-pm-separated atomic columns by a spherical aberration-corrected electron microscope with a 300-kV cold field emission gun. JOURNAL OF ELECTRON MICROSCOPY 2009; 58:357-361. [PMID: 19546144 DOI: 10.1093/jmicro/dfp030] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A spherical aberration-corrected electron microscope has been developed recently, which is equipped with a 300-kV cold field emission gun and an objective lens of a small chromatic aberration coefficient. A dumbbell image of 47 pm spacing, corresponding to a pair of atomic columns of germanium aligned along the [114] direction, is resolved in high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) with a 0.4-eV energy spread of the electron beam. The observed image was compared with a simulated image obtained by dynamical calculation.
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Affiliation(s)
- Hidetaka Sawada
- Japan Science and Technology Agency, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo, Japan.
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170
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Buban JP, Ramasse Q, Gipson B, Browning ND, Stahlberg H. High-resolution low-dose scanning transmission electron microscopy. JOURNAL OF ELECTRON MICROSCOPY 2009; 59:103-12. [PMID: 19915208 PMCID: PMC2857930 DOI: 10.1093/jmicro/dfp052] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 09/24/2009] [Indexed: 05/24/2023]
Abstract
During the past two decades instrumentation in scanning transmission electron microscopy (STEM) has pushed toward higher intensity electron probes to increase the signal-to-noise ratio of recorded images. While this is suitable for robust specimens, biological specimens require a much reduced electron dose for high-resolution imaging. We describe here protocols for low-dose STEM image recording with a conventional field-emission gun STEM, while maintaining the high-resolution capability of the instrument. Our findings show that a combination of reduced pixel dwell time and reduced gun current can achieve radiation doses comparable to low-dose TEM.
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MESH Headings
- Electrons
- Image Processing, Computer-Assisted
- Imaging, Three-Dimensional
- Microscopy, Electron, Scanning Transmission/instrumentation
- Microscopy, Electron, Scanning Transmission/methods
- Microscopy, Electron, Transmission/instrumentation
- Microscopy, Electron, Transmission/methods
- Oxides/chemistry
- Proteins/chemistry
- Strontium/chemistry
- Titanium/chemistry
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Affiliation(s)
- James P Buban
- Department of Molecular and Cellular Biology, College of Biological Sciences, University of California at Davis, 1 Shields Ave, Davis, CA, USA.
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171
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Zhou W, Ross-Medgaarden EI, Knowles WV, Wong MS, Wachs IE, Kiely CJ. Identification of active Zr–WOx clusters on a ZrO2 support for solid acid catalysts. Nat Chem 2009; 1:722-8. [DOI: 10.1038/nchem.433] [Citation(s) in RCA: 133] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Accepted: 10/01/2009] [Indexed: 11/09/2022]
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172
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Rulis P, Lupini A, Pennycook S, Ching W. Spectroscopic imaging of electron energy loss spectra using ab initio data and function field visualization. Ultramicroscopy 2009; 109:1472-8. [DOI: 10.1016/j.ultramic.2009.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2009] [Revised: 07/28/2009] [Accepted: 08/18/2009] [Indexed: 11/26/2022]
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173
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Findlay S, Shibata N, Ikuhara Y. What atomic resolution annular dark field imaging can tell us about gold nanoparticles on TiO2 (110). Ultramicroscopy 2009; 109:1435-46. [DOI: 10.1016/j.ultramic.2009.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 07/09/2009] [Accepted: 07/17/2009] [Indexed: 11/28/2022]
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174
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Ke X, Chen C, Yang J, Wu L, Zhou J, Li Q, Zhu Y, Kent PRC. Microstructure and a nucleation mechanism for nanoprecipitates in PbTe-AgSbTe2. PHYSICAL REVIEW LETTERS 2009; 103:145502. [PMID: 19905580 DOI: 10.1103/physrevlett.103.145502] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2008] [Indexed: 05/28/2023]
Abstract
Many recent advances in thermoelectric (TE) materials are attributed to their nanoscale constituents. Determination of the nanocomposite structures has represented a major experimental and computational challenge and eluded previous attempts. Here we present the first atomically resolved structures of high performance TE material PbTe-AgSbTe2 by transmission electron microscopy imaging and density functional theory calculations. The results establish an accurate structural characterization for PbTe-AgSbTe2 and identify the interplay of electric dipolar interactions and strain fields as the driving mechanism for nanoprecipitate nucleation and aggregation.
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Affiliation(s)
- Xuezhi Ke
- Department of Physics and High Pressure Science and Engineering Center, University of Nevada, Las Vegas, Nevada 89154, USA.
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175
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Zhu Y, Inada H, Nakamura K, Wall J. Imaging single atoms using secondary electrons with an aberration-corrected electron microscope. NATURE MATERIALS 2009; 8:808-812. [PMID: 19767737 DOI: 10.1038/nmat2532] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2009] [Accepted: 08/19/2009] [Indexed: 05/28/2023]
Abstract
Aberration correction has embarked on a new frontier in electron microscopy by overcoming the limitations of conventional round lenses, providing sub-angstrom-sized probes. However, improvement of spatial resolution using aberration correction so far has been limited to the use of transmitted electrons both in scanning and stationary mode, with an improvement of 20-40% (refs 3-8). In contrast, advances in the spatial resolution of scanning electron microscopes (SEMs), which are by far the most widely used instrument for surface imaging at the micrometre-nanometre scale, have been stagnant, despite several recent efforts. Here, we report a new SEM, with aberration correction, able to image single atoms by detecting electrons emerging from its surface as a result of interaction with the small probe. The spatial resolution achieved represents a fourfold improvement over the best-reported resolution in any SEM (refs 10-12). Furthermore, we can simultaneously probe the sample through its entire thickness with transmitted electrons. This ability is significant because it permits the selective visualization of bulk atoms and surface ones, beyond a traditional two-dimensional projection in transmission electron microscopy. It has the potential to revolutionize the field of microscopy and imaging, thereby opening the door to a wide range of applications, especially when combined with simultaneous nanoprobe spectroscopy.
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Affiliation(s)
- Y Zhu
- Brookhaven National Laboratory, Upton, New York 11973, USA.
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176
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Pennycook SJ, Chisholm MF, Lupini AR, Varela M, Borisevich AY, Oxley MP, Luo WD, van Benthem K, Oh SH, Sales DL, Molina SI, García-Barriocanal J, Leon C, Santamaría J, Rashkeev SN, Pantelides ST. Aberration-corrected scanning transmission electron microscopy: from atomic imaging and analysis to solving energy problems. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2009; 367:3709-3733. [PMID: 19687062 DOI: 10.1098/rsta.2009.0112] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The new possibilities of aberration-corrected scanning transmission electron microscopy (STEM) extend far beyond the factor of 2 or more in lateral resolution that was the original motivation. The smaller probe also gives enhanced single atom sensitivity, both for imaging and for spectroscopy, enabling light elements to be detected in a Z-contrast image and giving much improved phase contrast imaging using the bright field detector with pixel-by-pixel correlation with the Z-contrast image. Furthermore, the increased probe-forming aperture brings significant depth sensitivity and the possibility of optical sectioning to extract information in three dimensions. This paper reviews these recent advances with reference to several applications of relevance to energy, the origin of the low-temperature catalytic activity of nanophase Au, the nucleation and growth of semiconducting nanowires, and the origin of the eight orders of magnitude increased ionic conductivity in oxide superlattices. Possible future directions of aberration-corrected STEM for solving energy problems are outlined.
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Affiliation(s)
- S J Pennycook
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
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177
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Krivanek OL, Ursin JP, Bacon NJ, Corbin GJ, Dellby N, Hrncirik P, Murfitt MF, Own CS, Szilagyi ZS. High-energy-resolution monochromator for aberration-corrected scanning transmission electron microscopy/electron energy-loss spectroscopy. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2009; 367:3683-3697. [PMID: 19687060 DOI: 10.1098/rsta.2009.0087] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
An all-magnetic monochromator/spectrometer system for sub-30 meV energy-resolution electron energy-loss spectroscopy in the scanning transmission electron microscope is described. It will link the energy being selected by the monochromator to the energy being analysed by the spectrometer, without resorting to decelerating the electron beam. This will allow it to attain spectral energy stability comparable to systems using monochromators and spectrometers that are raised to near the high voltage of the instrument. It will also be able to correct the chromatic aberration of the probe-forming column. It should be able to provide variable energy resolution down to approximately 10 meV and spatial resolution less than 1 A.
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178
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Behan G, Cosgriff EC, Kirkland AI, Nellist PD. Three-dimensional imaging by optical sectioning in the aberration-corrected scanning transmission electron microscope. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2009; 367:3825-3844. [PMID: 19687068 DOI: 10.1098/rsta.2009.0074] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The depth resolution for optical sectioning in the scanning transmission electron microscope is measured using the results of optical sectioning experiments of laterally extended objects. We show that the depth resolution depends on the numerical aperture of the objective lens as expected. We also find, however, that the depth resolution depends on the lateral extent of the object that is being imaged owing to a missing cone of information in the transfer function. We find that deconvolution methods generally have limited usefulness in this case, but that three-dimensional information can still be obtained with the aid of prior information for specific samples such as those consisting of supported nanoparticles. We go on to review how a confocal geometry may improve the depth resolution for extended objects. Finally, we present a review of recent work exploring the effect of dynamical diffraction in zone-axis-aligned crystals on the optical sectioning process.
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Affiliation(s)
- G Behan
- Department of Materials, University of Oxford, Oxford OX1 3PH, UK
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179
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Kabius B, Hartel P, Haider M, Müller H, Uhlemann S, Loebau U, Zach J, Rose H. First application of Cc-corrected imaging for high-resolution and energy-filtered TEM. JOURNAL OF ELECTRON MICROSCOPY 2009; 58:147-55. [PMID: 19398781 DOI: 10.1093/jmicro/dfp021] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Contrast-transfer calculations indicate that C(c) correction should be highly beneficial for high-resolution and energy-filtered transmission electron microscopy. A prototype of an electron optical system capable of correcting spherical and chromatic aberration has been used to verify these calculations. A strong improvement in resolution at an acceleration voltage of 80 kV has been measured. Our first C(c)-corrected energy-filtered experiments examining a (LaAlO(3))(0.3)(Sr(2)AlTaO(6))(0.7)/LaCoO(3) interface demonstrated a significant gain for the spatial resolution in elemental maps of La.
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Affiliation(s)
- Bernd Kabius
- Argonne National Laboratory, Argonne IL 60439, USA.
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180
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Klie RF, Walkosz W, Yang G, Zhao Y. Aberration-corrected Z-contrast imaging of SrTiO3 dislocation cores. JOURNAL OF ELECTRON MICROSCOPY 2009; 58:185-191. [PMID: 19074689 DOI: 10.1093/jmicro/dfn026] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Many fundamental problems in materials science, physics, and particular nanotechnology rely on the direct determination and characterization of atomic arrangements and electronic environments of individual interfaces or defects. In this paper, we will show how aberration-corrected Z-contrast imaging in combination with electron energy-loss spectroscopy can be used to directly measure the local atomic and electronic structures of dislocation cores in low-angle SrTiO3 [001] tilt grain boundaries. In particular, we will study two types of dislocation cores in a 3 degrees tilt grain boundary, a pure edge dislocation, and a dissociated dislocation core. While it is energetically favorable for an edge dislocation to dissociate into two partial dislocations in such a low-angle grain boundary, we can find pure edge dislocations that show a higher O vacancy concentration than the dissociated cores. We suggest that the increased oxygen vacancy concentration might help stabilizing the pure edge dislocations in 3 degrees tilt grain boundaries of SrTiO3.
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Affiliation(s)
- R F Klie
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA.
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181
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Sanchez SI, Small MW, Zuo JM, Nuzzo RG. Structural Characterization of Pt−Pd and Pd−Pt Core−Shell Nanoclusters at Atomic Resolution. J Am Chem Soc 2009; 131:8683-9. [DOI: 10.1021/ja9020952] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sergio I. Sanchez
- Department of Chemistry and the Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, and Department of Materials Science and Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - Matthew W. Small
- Department of Chemistry and the Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, and Department of Materials Science and Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - Jian-min Zuo
- Department of Chemistry and the Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, and Department of Materials Science and Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
| | - Ralph G. Nuzzo
- Department of Chemistry and the Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, and Department of Materials Science and Engineering, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801
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182
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Erni R, Rossell MD, Kisielowski C, Dahmen U. Atomic-resolution imaging with a sub-50-pm electron probe. PHYSICAL REVIEW LETTERS 2009; 102:096101. [PMID: 19392535 DOI: 10.1103/physrevlett.102.096101] [Citation(s) in RCA: 227] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Indexed: 05/15/2023]
Abstract
Using a highly coherent focused electron probe in a fifth-order aberration-corrected transmission electron microscope, we report on resolving a crystal spacing less than 50 pm. Based on the geometrical source size and residual coherent and incoherent axial lens aberrations, an electron probe is calculated, which is theoretically capable of resolving an ideal 47 pm spacing with 29% contrast. Our experimental data show the 47 pm spacing of a Ge 114 crystal imaged with 11%-18% contrast at a 60%-95% confidence level, providing the first direct evidence for sub-50-pm resolution in annular dark-field scanning transmission electron microscopy imaging.
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Affiliation(s)
- Rolf Erni
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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183
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Chung SY, Choi SY, Yamamoto T, Ikuhara Y. Orientation-Dependent Arrangement of Antisite Defects in Lithium Iron(II) Phosphate Crystals. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200803520] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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184
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Chung SY, Choi SY, Yamamoto T, Ikuhara Y. Orientation-Dependent Arrangement of Antisite Defects in Lithium Iron(II) Phosphate Crystals. Angew Chem Int Ed Engl 2009; 48:543-6. [DOI: 10.1002/anie.200803520] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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185
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Molina S, Sales D, Galindo P, Fuster D, González Y, Alén B, González L, Varela M, Pennycook S. Column-by-column compositional mapping by Z-contrast imaging. Ultramicroscopy 2009; 109:172-6. [DOI: 10.1016/j.ultramic.2008.10.008] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Revised: 06/30/2008] [Accepted: 10/07/2008] [Indexed: 11/24/2022]
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186
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de Jonge N. Chapter 3 Carbon Nanotube Electron Sources for Electron Microscopes. ADVANCES IN IMAGING AND ELECTRON PHYSICS 2009. [DOI: 10.1016/s1076-5670(08)01403-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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187
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Hitachi's Development of Cold-Field Emission Scanning Transmission Electron Microscopes. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/s1076-5670(09)59004-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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188
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von Harrach H. Chapter 7 ***Development of the 300-kV Vacuum Generator STEM (1985–1996). ADVANCES IN IMAGING AND ELECTRON PHYSICS 2009. [DOI: 10.1016/s1076-5670(09)59007-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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189
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Kawasaki T, Ichihashi M, Matsutani T, Kimura Y, Ikuta T. Aberration analysis of Cs-corrector system with twin hexapoles and transfer lens doublet in scanning transmission electron microscope by simple ray tracing based on geometrical optics. SURF INTERFACE ANAL 2008. [DOI: 10.1002/sia.2957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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190
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Lupini AR, Pennycook SJ. Rapid autotuning for crystalline specimens from an inline hologram. Microscopy (Oxf) 2008; 57:195-201. [DOI: 10.1093/jmicro/dfn022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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191
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D’Alfonso A, Cosgriff E, Findlay S, Behan G, Kirkland A, Nellist P, Allen L. Three-dimensional imaging in double aberration-corrected scanning confocal electron microscopy, Part II: Inelastic scattering. Ultramicroscopy 2008; 108:1567-78. [DOI: 10.1016/j.ultramic.2008.05.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2008] [Revised: 05/14/2008] [Accepted: 05/20/2008] [Indexed: 11/16/2022]
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192
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Kisielowski C, Freitag B, Bischoff M, van Lin H, Lazar S, Knippels G, Tiemeijer P, van der Stam M, von Harrach S, Stekelenburg M, Haider M, Uhlemann S, Müller H, Hartel P, Kabius B, Miller D, Petrov I, Olson EA, Donchev T, Kenik EA, Lupini AR, Bentley J, Pennycook SJ, Anderson IM, Minor AM, Schmid AK, Duden T, Radmilovic V, Ramasse QM, Watanabe M, Erni R, Stach EA, Denes P, Dahmen U. Detection of single atoms and buried defects in three dimensions by aberration-corrected electron microscope with 0.5-A information limit. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2008; 14:469-477. [PMID: 18793491 DOI: 10.1017/s1431927608080902] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The ability of electron microscopes to analyze all the atoms in individual nanostructures is limited by lens aberrations. However, recent advances in aberration-correcting electron optics have led to greatly enhanced instrument performance and new techniques of electron microscopy. The development of an ultrastable electron microscope with aberration-correcting optics and a monochromated high-brightness source has significantly improved instrument resolution and contrast. In the present work, we report information transfer beyond 50 pm and show images of single gold atoms with a signal-to-noise ratio as large as 10. The instrument's new capabilities were exploited to detect a buried Sigma3 {112} grain boundary and observe the dynamic arrangements of single atoms and atom pairs with sub-angstrom resolution. These results mark an important step toward meeting the challenge of determining the three-dimensional atomic-scale structure of nanomaterials.
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Affiliation(s)
- C Kisielowski
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, One Cyclotron Rd., Berkeley, CA 94720, USA
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193
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Kimoto K, Ishizuka K, Matsui Y. Decisive factors for realizing atomic-column resolution using STEM and EELS. Micron 2008; 39:653-7. [DOI: 10.1016/j.micron.2007.09.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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194
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Klie RF, Zhao Y, Yang G, Zhu Y. High-resolution Z-contrast imaging and EELS study of functional oxide materials. Micron 2008; 39:723-33. [DOI: 10.1016/j.micron.2007.10.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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195
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Yakovlev S, Libera M. Dose-limited spectroscopic imaging of soft materials by low-loss EELS in the scanning transmission electron microscope. Micron 2008; 39:734-40. [DOI: 10.1016/j.micron.2007.10.019] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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196
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Bloch wave-based calculation of imaging properties of high-resolution scanning confocal electron microscopy. Ultramicroscopy 2008; 108:981-8. [DOI: 10.1016/j.ultramic.2008.04.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2007] [Revised: 04/02/2008] [Accepted: 04/15/2008] [Indexed: 11/22/2022]
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197
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198
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Dellby N, Krivanek O, Murfitt M. Optimized Quadrupole-Octupole C3/C5 Aberration Corrector for STEM. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.phpro.2008.07.094] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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199
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Urban KW. Studying Atomic Structures by Aberration-Corrected Transmission Electron Microscopy. Science 2008; 321:506-10. [DOI: 10.1126/science.1152800] [Citation(s) in RCA: 269] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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200
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Evans JE, Hetherington C, Kirkland A, Chang LY, Stahlberg H, Browning N. Low-dose aberration corrected cryo-electron microscopy of organic specimens. Ultramicroscopy 2008; 108:1636-44. [PMID: 18703285 DOI: 10.1016/j.ultramic.2008.06.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2007] [Revised: 05/28/2008] [Accepted: 06/17/2008] [Indexed: 12/01/2022]
Abstract
Spherical aberration (C(s)) correction in the transmission electron microscope has enabled sub-angstrom resolution imaging of inorganic materials. To achieve similar resolution for radiation-sensitive organic materials requires the microscope to be operated under hybrid conditions: low electron dose illumination of the specimen at liquid nitrogen temperature and low defocus values. Initial images from standard inorganic and organic test specimens have indicated that under these conditions C(s)-correction can provide a significant improvement in resolution (to less than 0.16nm) for direct imaging of organic samples.
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Affiliation(s)
- James E Evans
- Molecular and Cellular Biology, University of California, Davis, CA 95616, USA.
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