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Author | De Backer, A.; De Wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
Title | Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting: What are the limits? | Type | P1 Proceeding | ||
Year | 2015 | Publication | Journal of physics : conference series | Abbreviated Journal | |
Volume ![]() |
644 | Issue | 644 | Pages | 012034 |
Keywords | P1 Proceeding; Electron microscopy for materials research (EMAT) | ||||
Abstract | Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atom-counting diagnosed by combining a thorough statistical method and detailed image simulations. | ||||
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Language | Wos | 000366826200034 | Publication Date | 2015-10-13 | |
Series Editor | Series Title | Abbreviated Series Title | Electron Microscopy and Analysis Group Conference (EMAG), JUN 02-JUL 02, 2015, Manchester, ENGLAND | ||
Series Volume | Series Issue | Edition | |||
ISSN | 1742-6588 | ISBN | Additional Links | UA library record; WoS full record | |
Impact Factor | Times cited | Open Access | |||
Notes | The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project funding (G.0368.15N, G.0369.15N, and G.0374.15N) and a PhD research grant to A De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3), ERC Starting Grant 278510 Vortex, and the UK Engineering and Physical Sciences Research Council (EP/K032518/1). The authors acknowledge Johnson-Matthey for providing the sample and PhD funding to K E MacArthur. A Rosenauer is acknowledged for providing the STEMsim program.; esteem2jra2; ECASJO; | Approved | Most recent IF: NA | ||
Call Number | c:irua:130314 c:irua:130314 | Serial | 4050 | ||
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Author | de Backer, A.; De wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
Title | Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting : what are the limits? | Type | A1 Journal article | ||
Year | 2015 | Publication | Journal of physics : conference series | Abbreviated Journal | |
Volume ![]() |
644 | Issue | Pages | 012034-4 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atomcounting diagnosed by combining a thorough statistical method and detailed image simulations. | ||||
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Publisher | Place of Publication | Bristol | Editor | ||
Language | Wos | Publication Date | |||
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1742-6588; 1742-6596 | ISBN | Additional Links | UA library record | |
Impact Factor | Times cited | Open Access | |||
Notes | Approved | Most recent IF: NA | |||
Call Number | UA @ lucian @ c:irua:129198 | Serial | 4506 | ||
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Author | Idrissi, H.; Béché, A.; Gauquelin, N.; Ul-Haq, I.; Bollinger, C.; Demouchy, S.; Verbeeck, J.; Pardoen, T.; Schryvers, D.; Cordier, P. | ||||
Title | On the formation mechanisms of intragranular shear bands in olivine by stress-induced amorphization | Type | A1 Journal article | ||
Year | 2022 | Publication | Acta materialia | Abbreviated Journal | Acta Mater |
Volume ![]() |
239 | Issue | Pages | 118247-118249 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Intragranular amorphization shear lamellae are found in deformed olivine aggregates. The detailed trans-mission electron microscopy analysis of intragranular lamella arrested in the core of a grain provides novel information on the amorphization mechanism. The deformation field is complex and heteroge-neous, corresponding to a shear crack type instability involving mode I, II and III loading components. The formation and propagation of the amorphous lamella is accompanied by the formation of crystal defects ahead of the tip. These defects are geometrically necessary [001] dislocations, characteristics of high-stress deformation in olivine, and rotational nanodomains which are tentatively interpreted as disclinations. We show that these defects play an important role in dictating the path followed by the amorphous lamella. Stress-induced amorphization in olivine would thus result from a direct crystal-to -amorphous transformation associated with a shear instability and not from a mechanical destabilization due to the accumulation of high number of defects from an intense preliminary deformation. The pref-erential alignment of some lamellae along (010) is a proof of the lower ultimate mechanical strength of these planes.(c) 2022 The Authors. Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ ) | ||||
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Language | Wos | 000861076600004 | Publication Date | 2022-08-05 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 1359-6454 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 9.4 | Times cited | 5 | Open Access | OpenAccess |
Notes | The QuanTEM microscope was partially funded by the Flemish government. The K2 camera was funded by FWO Hercules fund G0H4316N 'Direct electron detector for soft matter TEM'. A. Beche acknowledges funding from FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy'). H. Idrissi is mandated by the Belgian National Fund for Scientific Research (FSR-FNRS). This work was supported by the FNRS under Grant PDR – T011322F and by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme under grant agreement No 787,198 Time Man. J-L Rouviere is acknowledged for his support with the GPA softawre. | Approved | Most recent IF: 9.4 | ||
Call Number | UA @ admin @ c:irua:191432 | Serial | 7186 | ||
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Author | Jannis, D.; Hofer, C.; Gao, C.; Xie, X.; Béché, A.; Pennycook, Tj.; Verbeeck, J. | ||||
Title | Event driven 4D STEM acquisition with a Timepix3 detector: Microsecond dwell time and faster scans for high precision and low dose applications | Type | A1 Journal article | ||
Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
233 | Issue | Pages | 113423 | |
Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
Abstract | Four dimensional scanning transmission electron microscopy (4D STEM) records the scattering of electrons in a material in great detail. The benefits offered by 4D STEM are substantial, with the wealth of data it provides facilitating for instance high precision, high electron dose efficiency phase imaging via centre of mass or ptychography based analysis. However the requirement for a 2D image of the scattering to be recorded at each probe position has long placed a severe bottleneck on the speed at which 4D STEM can be performed. Recent advances in camera technology have greatly reduced this bottleneck, with the detection efficiency of direct electron detectors being especially well suited to the technique. However even the fastest frame driven pixelated detectors still significantly limit the scan speed which can be used in 4D STEM, making the resulting data susceptible to drift and hampering its use for low dose beam sensitive applications. Here we report the development of the use of an event driven Timepix3 direct electron camera that allows us to overcome this bottleneck and achieve 4D STEM dwell times down to 100 ns; orders of magnitude faster than what has been possible with frame based readout. We characterize the detector for different acceleration voltages and show that the method is especially well suited for low dose imaging and promises rich datasets without compromising dwell time when compared to conventional STEM imaging. | ||||
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Publisher | Place of Publication | Editor | |||
Language | Wos | 000734396800003 | Publication Date | 2021-11-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | 31 | Open Access | OpenAccess |
Notes | This project has received funding from the Euro- pean Union’s Horizon 2020 Research Infrastructure – Integrating Activities for Advanced Communities under grant agreement No 823717 – ESTEEM3. J.V. and A.B. acknowledge funding from FWO project G093417N (‘Compressed sensing enabling low dose imaging in transmission electron microscopy’). J.V. and D.J. ac- knowledge funding from FWO project G042920N ‘Co- incident event detection for advanced spectroscopy in transmission electron microscopy’. We acknowledge funding under the European Union’s Horizon 2020 re- search and innovation programme (J.V. and D.J un- der grant agreement No 101017720, FET-Proactive EBEAM, and C.H., C.G., X.X. and T.J.P. from the Eu- ropean Research Council (ERC) Grant agreement No. 802123-HDEM).; esteem3JRA; esteem3reported | Approved | Most recent IF: 2.2 | ||
Call Number | EMAT @ emat @c:irua:183948 | Serial | 6828 | ||
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Author | Velazco, A.; Béché, A.; Jannis, D.; Verbeeck, J. | ||||
Title | Reducing electron beam damage through alternative STEM scanning strategies, Part I: Experimental findings | Type | A1 Journal article | ||
Year | 2022 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
232 | Issue | Pages | 113398 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The highly energetic electrons in a transmission electron microscope (TEM) can alter or even completely destroy the structure of samples before sufficient information can be obtained. This is especially problematic in the case of zeolites, organic and biological materials. As this effect depends on both the electron beam and the sample and can involve multiple damage pathways, its study remained difficult and is plagued with irreproducibility issues, circumstantial evidence, rumors, and a general lack of solid data. Here we take on the experimental challenge to investigate the role of the STEM scan pattern on the damage behavior of a commercially available zeolite sample with the clear aim to make our observations as reproducible as possible. We make use of a freely programmable scan engine that gives full control over the tempospatial distribution of the electron probe on the sample and we use its flexibility to obtain multiple repeated experiments under identical conditions comparing the difference in beam damage between a conventional raster scan pattern and a newly proposed interleaved scan pattern that provides exactly the same dose and dose rate and visits exactly the same scan points. We observe a significant difference in beam damage for both patterns with up to 11 % reduction in damage (measured from mass loss). These observations demonstrate without doubt that electron dose, dose rate and acceleration voltage are not the only parameters affecting beam damage in (S)TEM experiments and invite the community to rethink beam damage as an unavoidable consequence of applied electron dose. | ||||
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Language | Wos | 000714819200002 | Publication Date | 2021-10-02 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | 18 | Open Access | OpenAccess |
Notes | A.V., D.J., A.B. and J.V. acknowledge funding from FWO project G093417N (’Compressed sensing enabling low dose imaging in transmission electron microscopy’) and G042920N (’Coincident event detection for advanced spectroscopy in transmission electron microscopy’). This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 823717 ESTEEM3. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. J.V. acknowledges funding from GOA project “Solarpaint” of the University of Antwerp.; JRA; reported | Approved | Most recent IF: 2.2 | ||
Call Number | EMAT @ emat @c:irua:183282 | Serial | 6818 | ||
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Author | Vanrompay, H.; Skorikov, A.; Bladt, E.; Béché, A.; Freitag, B.; Verbeeck, J.; Bals, S. | ||||
Title | Fast versus conventional HAADF-STEM tomography of nanoparticles: advantages and challenges | Type | A1 Journal article | ||
Year | 2021 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
221 | Issue | Pages | 113191 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | HAADF-STEM tomography is a widely used experimental technique for analyzing nanometer-scale crystalline structures of a large variety of materials in three dimensions. Unfortunately, the acquisition of conventional HAADF-STEM tilt series can easily take up one hour or more, depending on the complexity of the experiment. It is therefore far from straightforward to investigate samples that do not withstand long acquisition or to acquire large amounts of tilt series during a single TEM experiment. The latter would lead to the ability to obtain statistically meaningful 3D data, or to perform in situ 3D characterizations with a much shorter time resolution. Various HAADF-STEM acquisition strategies have been proposed to accelerate the tomographic acquisition and reduce the required electron dose. These methods include tilting the holder continuously while acquiring a projection “movie” and a hybrid, incremental, methodology which combines the benefits of the conventional and continuous technique. However, until now an experimental evaluation has been lacking. In this paper, the different acquisition strategies will be experimentally compared in terms of speed, resolution and electron dose. This evaluation will be performed based on experimental tilt series acquired for various metallic nanoparticles with different shapes and sizes. We discuss the data processing involved with the fast HAADF-STEM tilt series and provide a general guideline when which acquisition strategy should be preferentially used. | ||||
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Language | Wos | 000612539600003 | Publication Date | 2020-12-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 15 | Open Access | OpenAccess |
Notes | We acknowledge Prof. Luis M. Liz-Marzán and co-workers of the Bionanoplasmonics Laboratory, CIC biomaGUNE, Spain for providing the Au@Ag nanoparticles, Prof. Sara. E. Skrabalak and co-workers of Indiana University, United States for the provision of the Au octopods and Prof. Teri W. Odom of Northwestern University, United States for the provision of the Au nanostars. H.V. acknowledges financial support by the Research Foundation Flanders (FWO grant 1S32617N). S.B acknowledges financial support by the Research Foundation Flanders (FWO grant G.0381.16N). This project received funding as well from the European Union’s Horizon 2020 research and innovation program under grant agreement No 731019 (EUSMI) and No 815128 (REALNANO). The authors acknowledge the entire EMAT technical staff for their support.; sygma | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:174551 | Serial | 6660 | ||
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Author | Prabhakara, V.; Jannis, D.; Guzzinati, G.; Béché, A.; Bender, H.; Verbeeck, J. | ||||
Title | HAADF-STEM block-scanning strategy for local measurement of strain at the nanoscale | Type | A1 Journal article | ||
Year | 2020 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
219 | Issue | Pages | 113099 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Lattice strain measurement of nanoscale semiconductor devices is crucial for the semiconductor industry as strain substantially improves the electrical performance of transistors. High resolution scanning transmission electron microscopy (HR-STEM) imaging is an excellent tool that provides spatial resolution at the atomic scale and strain information by applying Geometric Phase Analysis or image fitting procedures. However, HR-STEM images regularly suffer from scanning distortions and sample drift during image acquisition. In this paper, we propose a new scanning strategy that drastically reduces artefacts due to drift and scanning distortion, along with extending the field of view. It consists of the acquisition of a series of independent small subimages containing an atomic resolution image of the local lattice. All subimages are then analysed individually for strain by fitting a nonlinear model to the lattice images. The method allows flexible tuning of spatial resolution and the field of view within the limits of the dynamic range of the scan engine while maintaining atomic resolution sampling within the subimages. The obtained experimental strain maps are quantitatively benchmarked against the Bessel diffraction technique. We demonstrate that the proposed scanning strategy approaches the performance of the diffraction technique while having the advantage that it does not require specialized diffraction cameras. | ||||
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Language | Wos | 000594768500006 | Publication Date | 2020-09-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.2 | Times cited | 4 | Open Access | OpenAccess |
Notes | A.B. D.J. and J.V. acknowledge funding through FWO project G093417N ('Compressed sensing enabling low dose imaging in transmission electron microscopy') from the Flanders Research Fund. J.V acknowledges funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 823717 – ESTEEM3. The Qu-Ant-EM microscope and the direct electron detector used in the diffraction experiments was partly funded by the Hercules fund from the Flemish Government. This project has received funding from the GOA project “Solarpaint” of the University of Antwerp. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek – Vlaanderen (FWO). Special thanks to Dr. Thomas Nuytten, Prof. Dr. Wilfried Vandervorst, Dr. Paola Favia, Dr. Olivier Richard from IMEC, Leuven and Prof. Dr. Sara Bals from EMAT, Antwerp for their continuous support and collaboration with the project and to the IMEC processing group for the device fabrication. | Approved | Most recent IF: 2.2; 2020 IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:172485 | Serial | 6404 | ||
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Author | Jalabert, D.; Pelloux-Gervais, D.; Béché, A.; Hartmann, J.M.; Gergaud, P.; Rouvière, J.L.; Canut, B. | ||||
Title | Depth strain profile with sub-nm resolution in a thin silicon film using medium energy ion scattering | Type | A1 Journal article | ||
Year | 2012 | Publication | Physica Status Solidi A-Applications And Materials Science | Abbreviated Journal | Phys Status Solidi A |
Volume ![]() |
209 | Issue | 2 | Pages | 265-267 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The depth strain profile in silicon from the Si (001) substrate to the surface of a 2 nm thick Si/12 nm thick SiGe/bulk Si heterostructure has been determined by medium energy ion scattering (MEIS). It shows with sub-nanometer resolution and high strain sensitivity that the thin Si cap presents residual compressive strain caused by Ge diffusion coming from the fully strained SiGe layer underneath. The strain state of the SiGe buffer have been checked by X-ray diffraction (XRD) and nano-beam electron diffraction (NBED) measurements. | ||||
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Language | Wos | 000303382700005 | Publication Date | 2011-11-11 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 1862-6300; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.775 | Times cited | 3 | Open Access | |
Notes | Approved | Most recent IF: 1.775; 2012 IF: 1.469 | |||
Call Number | UA @ lucian @ c:irua:136430 | Serial | 4497 | ||
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Author | Müller-Caspary, K.; Krause, F.F.; Winkler, F.; Béché, A.; Verbeeck, J.; Van Aert, S.; Rosenauer, A. | ||||
Title | Comparison of first moment STEM with conventional differential phase contrast and the dependence on electron dose | Type | A1 Journal article | ||
Year | 2019 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
203 | Issue | 203 | Pages | 95-104 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | This study addresses the comparison of scanning transmission electron microscopy (STEM) measurements of momentum transfers using the first moment approach and the established method that uses segmented annular detectors. Using an ultrafast pixelated detector to acquire four-dimensional, momentum-resolved STEM signals, both the first moment calculation and the calculation of the differential phase contrast (DPC) signals are done for the same experimental data. In particular, we investigate the ability to correct the segment-based signal to yield a suitable approximation of the first moment for cases beyond the weak phase object approximation. It is found that the measurement of momentum transfers using segmented detectors can approach the first moment measurement as close as 0.13 h/nm in terms of a root mean square (rms) difference in 10 nm thick SrTiO3 for a detector with 16 segments. This amounts to 35% of the rms of the momentum transfers. In addition, we present a statistical analysis of the precision of first moment STEM as a function of dose. For typical experimental settings with recent hardware such as a Medipix3 Merlin camera attached to a probe-corrected STEM, we find that the precision of the measurement of momentum transfers stagnates above certain doses. This means that other instabilities such as specimen drift or scan noise have to be taken into account seriously for measurements that target, e.g., the detection of bonding effects in the charge density. | ||||
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Language | Wos | 000465021000013 | Publication Date | 2018-12-30 | |
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Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 25 | Open Access | OpenAccess |
Notes | ; The direct electron detector (Medipix3 Merlin) was funded by the Hercules fund from the Flemish Government. K. Muller-Caspary acknowledges funding from the Initiative and Network Fund of the Helmholtz Association within the framework of the Helmholtz Young Investigator Group moreSTEM (VH-NG-1317) at Forschungszentrum Julich, Germany. F. F. Krause acknowledges funding from the Central Research Development Fund of the University of Bremen, Germany. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) and the Research Fund of the University of Antwerp. ; | Approved | Most recent IF: 2.843 | ||
Call Number | UA @ admin @ c:irua:160213 | Serial | 5242 | ||
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Author | Verbeeck, J.; Béché, A.; Müller-Caspary, K.; Guzzinati, G.; Luong, M.A.; Den Hertog, M. | ||||
Title | Demonstration of a 2 × 2 programmable phase plate for electrons | Type | A1 Journal article | ||
Year | 2018 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
190 | Issue | Pages | 58-65 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | First results on the experimental realisation of a 2 × 2 programmable phase plate for electrons are presented. The design consists of an array of electrostatic elements that influence the phase of electron waves passing through 4 separately controllable aperture holes. This functionality is demonstrated in a conventional transmission electron microscope operating at 300 kV and results are in very close agreement with theoretical predictions. The dynamic creation of a set of electron probes with different phase symmetry is demonstrated, thereby bringing adaptive optics in TEM one step closer to reality. The limitations of the current design and how to overcome these in the future are discussed. Simulations show how further evolved versions of the current proof of concept might open new and exciting application prospects for beam shaping and aberration correction. | ||||
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Language | Wos | 000432868800007 | Publication Date | 2018-04-18 | |
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ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 73 | Open Access | Not_Open_Access: Available from 19.04.2020 |
Notes | J.V. and A.B. acknowledge funding from the Fund for Scientific Research Flanders FWO project G093417N and the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX and ERC proof of concept project DLV-789598 ADAPTEM. The Qu-Ant-EM microscope used in this work was partly funded by the Hercules fund from the Flemish Government. MdH acknowledges financial support from the ANRCOSMOS (ANR-12-JS10-0002). MdH and ML acknowledge funding from the Laboratoire d’excellence LANEF in Grenoble (ANR-10-LABX-51-01). | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @c:irua:150459UA @ admin @ c:irua:150459 | Serial | 4920 | ||
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Author | Gauquelin, N.; van den Bos, K.H.W.; Béché, A.; Krause, F.F.; Lobato, I.; Lazar, S.; Rosenauer, A.; Van Aert, S.; Verbeeck, J. | ||||
Title | Determining oxygen relaxations at an interface: A comparative study between transmission electron microscopy techniques | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
181 | Issue | 181 | Pages | 178-190 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Nowadays, aberration corrected transmission electron microscopy (TEM) is a popular method to characterise nanomaterials at the atomic scale. Here, atomically resolved images of nanomaterials are acquired, where the contrast depends on the illumination, imaging and detector conditions of the microscope. Visualization of light elements is possible when using low angle annular dark field (LAADF) STEM, annular bright field (ABF) STEM, integrated differential phase contrast (iDPC) STEM, negative spherical aberration imaging (NCSI) and imaging STEM (ISTEM). In this work, images of a NdGaO3-La0.67Sr0.33MnO3 (NGO-LSMO) interface are quantitatively evaluated by using statistical parameter estimation theory. For imaging light elements, all techniques are providing reliable results, while the techniques based on interference contrast, NCSI and ISTEM, are less robust in terms of accuracy for extracting heavy column locations. In term of precision, sample drift and scan distortions mainly limits the STEM based techniques as compared to NCSI. Post processing techniques can, however, partially compensate for this. In order to provide an outlook to the future, simulated images of NGO, in which the unavoidable presence of Poisson noise is taken into account, are used to determine the ultimate precision. In this future counting noise limited scenario, NCSI and ISTEM imaging will provide more precise values as compared to the other techniques, which can be related to the mechanisms behind the image recording. | ||||
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Language | Wos | 000411170800022 | Publication Date | 2017-06-03 | |
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ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 34 | Open Access | OpenAccess |
Notes | The authors acknowledge financial support from Flanders (FWO, Belgium) through project fundings (G.0044.13N, G.0374.13N, G.0368.15N, G.0369.15N), and by a Ph.D. grant to K.H.W.v.d.B. The Qu-Ant-EM microscope used for this study was partly funded by the Hercules fund from the Flemish Government. A.B. and N.G. acknowledge the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no.280432) which partly funded this study. N.G., A.B. and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant 278510 VORTEX. The research leading to these results has received funding from the Deutsche Forschungsgemeinschaft under Contract No. RO 2057/4-2 and the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2. We thank Prof. G. Koster from the University of Twente for kindly providing us with the LSMO-NGO test sample. | Approved | Most recent IF: 2.843 | ||
Call Number | EMAT @ emat @ c:irua:144435UA @ admin @ c:irua:144435 | Serial | 4620 | ||
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Author | Béché, A.; Juchtmans, R.; Verbeeck, J. | ||||
Title | Efficient creation of electron vortex beams for high resolution STEM imaging | Type | A1 Journal article | ||
Year | 2017 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
178 | Issue | 178 | Pages | 12-19 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The recent discovery of electron vortex beams carrying quantised angular momentum in the TEM has led to an active field of research, exploring a variety of potential applications including the possibility of mapping magnetic states at the atomic scale. A prerequisite for this is the availability of atomic sized electron vortex beams at high beam current and mode purity. In this paper we present recent progress showing that by making use of the Aharonov-Bohm effect near the tip of a long single domain ferromagnetic Nickel needle, a very efficient aperture for the production of electron vortex beams can be realised. The aperture transmits more than 99% of all electrons and provides a vortex mode purity of up to 92%. Placing this aperture in the condenser plane of a state of the art Cs corrected microscope allows us to demonstrate atomic resolution HAADF STEM images with spatial resolution better than 1 Angstrom, in agreement with theoretical expectations and only slightly inferior to the performance of a non-vortex probe on the same instrument. | ||||
Address | EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium | ||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | English | Wos | 000403862900003 | Publication Date | 2016-05-10 |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 30 | Open Access | OpenAccess |
Notes | A.B. and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. J.V. acknowledges funding from FWO project G.0044.13N ('Charge ordering').; ECASJO_; | Approved | Most recent IF: 2.843 | ||
Call Number | c:irua:134085 c:irua:134085UA @ admin @ c:irua:134085 | Serial | 4094 | ||
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Author | Martinez, G.T.; Jones, L.; de Backer, A.; Béché, A.; Verbeeck, J.; Van Aert, S.; Nellist, P.D. | ||||
Title | Quantitative STEM normalisation : the importance of the electron flux | Type | A1 Journal article | ||
Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
159 | Issue | 159 | Pages | 46-58 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Annular dark-field (ADF) scanning transmission electron microscopy (STEM) has become widely used in quantitative studies based on the opportunity to directly compare experimental and simulated images. This comparison merely requires the experimental data to be normalised and expressed in units of fractional beam-current. However, inhomogeneities in the response of electron detectors can complicate this normalisation. The quantification procedure becomes both experiment and instrument specific, requiring new simulations for the particular response of each instrument's detector, and for every camera-length used. This not only impedes the comparison between different instruments and research groups, but can also be computationally very time consuming. Furthermore, not all image simulation methods allow for the inclusion of an inhomogeneous detector response. In this work, we propose an alternative method for normalising experimental data in order to compare these with simulations that consider a homogeneous detector response. To achieve this, we determine the electron flux distribution reaching the detector by means of a camera-length series or a so-called atomic column cross-section averaged convergent beam electron diffraction (XSACBED) pattern. The result is then used to determine the relative weighting of the detector response. Here we show that the results obtained by this new electron flux weighted (EFW) method are comparable to the currently used method, while considerably simplifying the needed simulation libraries. The proposed method also allows one to obtain a metric that describes the quality of the detector response in comparison with the ideal detector response. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000366220000006 | Publication Date | 2015-08-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 27 | Open Access | |
Notes | 246791 Countatoms; 278510 Vortex; 312483 Esteem2; Fwo G036815; G036915; G037413; G004413; esteem2ta ECASJO; | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
Call Number | c:irua:127293 c:irua:127293UA @ admin @ c:irua:127293 | Serial | 2762 | ||
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Author | de Backer, A.; Martinez, G.T.; MacArthur, K.E.; Jones, L.; Béché, A.; Nellist, P.D.; Van Aert, S. | ||||
Title | Dose limited reliability of quantitative annular dark field scanning transmission electron microscopy for nano-particle atom-counting | Type | A1 Journal article | ||
Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
151 | Issue | 151 | Pages | 56-61 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Quantitative annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique to characterise nano-particles on an atomic scale. Because of their limited size and beam sensitivity, the atomic structure of such particles may become extremely challenging to determine. Therefore keeping the incoming electron dose to a minimum is important. However, this may reduce the reliability of quantitative ADF STEM which will here be demonstrated for nano-particle atom-counting. Based on experimental ADF STEM images of a real industrial catalyst, we discuss the limits for counting the number of atoms in a projected atomic column with single atom sensitivity. We diagnose these limits by combining a thorough statistical method and detailed image simulations. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000351237800008 | Publication Date | 2014-12-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 29 | Open Access | |
Notes | 312483 Esteem2; 278510 Vortex; Fwo G039311; G006410; G037413; esteem2ta; ECASJO; | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
Call Number | c:irua:123927 c:irua:123927 | Serial | 753 | ||
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Author | Guzzinati, G.; Clark, L.; Béché, A.; Juchtmans, R.; Van Boxem, R.; Mazilu, M.; Verbeeck, J. | ||||
Title | Prospects for versatile phase manipulation in the TEM : beyond aberration correction | Type | A1 Journal article | ||
Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
151 | Issue | 151 | Pages | 85-93 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | In this paper we explore the desirability of a transmission electron microscope in which the phase of the electron wave can be freely controlled. We discuss different existing methods to manipulate the phase of the electron wave and their limitations. We show how with the help of current techniques the electron wave can already be crafted into specific classes of waves each having their own peculiar properties. Assuming a versatile phase modulation device is feasible, we explore possible benefits and methods that could come into existence borrowing from light optics where the so-called spatial light modulators provide programmable phase plates for quite some time now. We demonstrate that a fully controllable phase plate building on Harald Rose׳s legacy in aberration correction and electron optics in general would open an exciting field of research and applications. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000351237800012 | Publication Date | 2014-10-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 19 | Open Access | |
Notes | 278510 Vortex; Fwo; 312483 Esteem2; esteem2jra2; esteem2jra3 ECASJO_; | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
Call Number | c:irua:121405 c:irua:121405UA @ admin @ c:irua:121405 | Serial | 2731 | ||
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Author | Béché, A.; Rouviere, J.L.; Barnes, J.P.; Cooper, D. | ||||
Title | Strain measurement at the nanoscale : comparison between convergent beam electron diffraction, nano-beam electron diffraction, high resolution imaging and dark field electron holography | Type | A1 Journal article | ||
Year | 2013 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
131 | Issue | Pages | 10-23 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Convergent beam electron diffraction (CBED), nano-beam electron diffraction (NBED or NBD), high resolution imaging (HRTEM and HRSTEM) and dark field electron holography (DFEH or HoloDark) are five TEM based techniques able to quantitatively measure strain at the nanometer scale. In order to demonstrate the advantages and disadvantages of each technique, two samples composed of epitaxial silicon-germanium layers embedded in a silicon matrix have been investigated. The five techniques are then compared in terms of strain precision and accuracy, spatial resolution, field of view, mapping abilities and ease of performance and analysis. (C) 2013 Elsevier By. All rights reserved. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000322631200002 | Publication Date | 2013-04-06 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 73 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2013 IF: 2.745 | |||
Call Number | UA @ lucian @ c:irua:109774 | Serial | 3171 | ||
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Author | Bhat, S.G.; Gauquelin, N.; Sebastian, N.K.; Sil, A.; Béché, A.; Verbeeck, J.; Samal, D.; Kumar, P.S.A. | ||||
Title | Orthorhombic vs. hexagonal epitaxial SrIrO3 thin films : structural stability and related electrical transport properties | Type | A1 Journal article | ||
Year | 2018 | Publication | Europhysics letters | Abbreviated Journal | Epl-Europhys Lett |
Volume ![]() |
122 | Issue | 2 | Pages | 28003 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Metastable orthorhombic SrIrO3 (SIO) is an arch-type spin-orbit coupled material. We demonstrate here a controlled growth of relatively thick (200 nm) SIO films that transform from bulk “6H-type” structure with monoclinic distortion to an orthorhombic lattice by controlling growth temperature. Extensive studies based on high-resolution X-ray diffraction and transmission electron microscopy infer a two distinct structural phases of SIO. Electrical transport reveals a weak temperature-dependent semi-metallic character for both phases. However, the temperature-dependent Hall-coefficient for the orthorhombic SIO exhibits a prominent sign change, suggesting a multiband character in the vicinity of E-F. Our findings thus unravel the subtle structure-property relation in SIO epitaxial thin films. Copyright (C) EPLA, 2018 | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Paris | Editor | ||
Language | Wos | 000435517300001 | Publication Date | 2018-06-18 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0295-5075 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 1.957 | Times cited | 4 | Open Access | Not_Open_Access |
Notes | ; SGB and DS acknowledge useful discussions with E. P. Houwman, University of Twente, on X-ray diffraction. DS would like to thank H. Takagi, Max-Planck Institute for Solid State Research, Stuttgart, for the fruitful discussion on the transport properties of SIO thin films. SGB and NKS thank A. Aravind, Bishop Moore College, Mavelikara, for his valuable inputs while depositing the thin films of SIO. SGB, NKS and PSAK acknowledge Nano Mission Council, Department of Science & Technology, India, for the funding. DS acknowledges the financial support from Max-Planck Society through MaxPlanck Partner Group. NG, AB and JV acknowledge funding from GOA project “Solarpaint” of the University of Antwerp and FWO project G093417N. ; | Approved | Most recent IF: 1.957 | ||
Call Number | UA @ lucian @ c:irua:152074UA @ admin @ c:irua:152074 | Serial | 5034 | ||
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Author | Van Aert, S.; De Backer, A.; Jones, L.; Martinez, G.T.; Béché, A.; Nellist, P.D. | ||||
Title | Control of Knock-On Damage for 3D Atomic Scale Quantification of Nanostructures: Making Every Electron Count in Scanning Transmission Electron Microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume ![]() |
122 | Issue | 6 | Pages | 066101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Understanding nanostructures down to the atomic level is the key to optimizing the design of advancedmaterials with revolutionary novel properties. This requires characterization methods capable of quantifying the three-dimensional (3D) atomic structure with the highest possible precision. A successful approach to reach this goal is to count the number of atoms in each atomic column from 2D annular dark field scanning transmission electron microscopy images. To count atoms with single atom sensitivity, a minimum electron dose has been shown to be necessary, while on the other hand beam damage, induced by the high energy electrons, puts a limit on the tolerable dose. An important challenge is therefore to develop experimental strategies to optimize the electron dose by balancing atom-counting fidelity vs the risk of knock-on damage. To achieve this goal, a statistical framework combined with physics-based modeling of the dose-dependent processes is here proposed and experimentally verified. This model enables an investigator to theoretically predict, in advance of an experimental measurement, the optimal electron dose resulting in an unambiguous quantification of nanostructures in their native state with the highest attainable precision. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000458824200008 | Publication Date | 2019-02-13 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 3 | Open Access | OpenAccess |
Notes | This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant Agreement No. 770887). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (WO.010.16N, G.0934.17N, G.0502.18N, G.0267.18N), and a grant to A. D. B. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement No. 312483— ESTEEM2 (Integrated Infrastructure Initiative-I3) and the UK EPSRC (Grant No. EP/M010708/1). | Approved | Most recent IF: 8.462 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:157175 | Serial | 5156 | ||
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Author | Gao, C.; Hofer, C.; Jannis, D.; Béché, A.; Verbeeck, J.; Pennycook, T.J. | ||||
Title | Overcoming contrast reversals in focused probe ptychography of thick materials: An optimal pipeline for efficiently determining local atomic structure in materials science | Type | A1 Journal article | ||
Year | 2022 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
121 | Issue | 8 | Pages | 081906 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Ptychography provides highly efficient imaging in scanning transmission electron microscopy (STEM), but questions have remained over its applicability to strongly scattering samples such as those most commonly seen in materials science. Although contrast reversals can appear in ptychographic phase images as the projected potentials of the sample increase, we show here how these can be easily overcome by a small amount of defocus. The amount of defocus is small enough that it not only can exist naturally when focusing using the annular dark field (ADF) signal but can also be adjusted post acquisition. The ptychographic images of strongly scattering materials are clearer at finite doses than other STEM techniques and can better reveal light atomic columns within heavy lattices. In addition, data for ptychography can now be collected simultaneously with the fastest of ADF scans. This combination of sensitivity and interpretability presents an ideal workflow for materials science. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000844403300006 | Publication Date | 2022-08-22 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 4 | Times cited | 9 | Open Access | OpenAccess |
Notes | European Research Council, 802123-HDEM ; HORIZON EUROPE European Research Council, 823717-ESTEEM3 ; Fonds Wetenschappelijk Onderzoek, G042920N ; Fonds Wetenschappelijk Onderzoek, G042820N ; Horizon 2020 Framework Programme, 101017720 ; Fonds Wetenschappelijk Onderzoek, G013122N ; esteem3reported; esteem3jra | Approved | Most recent IF: 4 | ||
Call Number | EMAT @ emat @c:irua:190670 | Serial | 7120 | ||
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Author | Verbeeck, J.; Béché, A.; van den Broek, W. | ||||
Title | A holographic method to measure the source size broadening in STEM | Type | A1 Journal article | ||
Year | 2012 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
120 | Issue | Pages | 35-40 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Source size broadening is an important resolution limiting effect in modern STEM experiments. Here, we propose an alternative method to measure the source size broadening making use of a holographic biprism to create interference patterns in an empty Ronchigram. This allows us to measure the exact shape of the source size broadening with a much better sampling than previously possible. We find that the shape of the demagnified source deviates considerably from a Gaussian profile that is often assumed. We fit the profile with a linear combination of a Gaussian and a bivariate Cauchy distribution showing that even though the full width at half maximum is similar to previously reported measurements, the tails of the profile are considerable wider. This is of fundamental importance for quantitative comparison of STEM simulations with experiments as these tails make the image contrast dependent on the interatomic distance, an effect that cannot be reproduced by a single Gaussian profile of fixed width alone. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000308082600005 | Publication Date | 2012-06-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 29 | Open Access | |
Notes | This work was supported by funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant no. 246791 COUNTATOMS and ERC Starting Grant 278510 VORTEX. The Qu-Ant-EM microscope was partly funded by the Hercules fund from the Flemish Government. W. Van den Broek acknowledges funding from the Condor project, a project under the supervision of the Embedded Systems Institute (ESI) and FEI. This project is partially supported by the Dutch Ministry of Economic Affairs under the BSIK program. ECASJO_; | Approved | Most recent IF: 2.843; 2012 IF: 2.470 | ||
Call Number | UA @ lucian @ c:irua:100466UA @ admin @ c:irua:100466 | Serial | 1483 | ||
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Author | Lubk, A.; Béché, A.; Verbeeck, J. | ||||
Title | Electron Microscopy of Probability Currents at Atomic Resolution | Type | A1 Journal article | ||
Year | 2015 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume ![]() |
115 | Issue | 115 | Pages | 176101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Atomic resolution transmission electron microscopy records the spatially resolved scattered electron density to infer positions, density, and species of atoms. These data are indispensable for studying the relation between structure and properties in solids. Here, we show how this signal can be augmented by the lateral probability current of the scattered electrons in the object plane at similar resolutions and fields of view. The currents are reconstructed from a series of three atomic resolution TEM images recorded under a slight difference of perpendicular line foci. The technique does not rely on the coherence of the electron beam and can be used to reveal electric, magnetic, and strain fields with incoherent electron beams as well as correlations in inelastic transitions, such as electron magnetic chiral dichroism. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000363023700011 | Publication Date | 2015-10-20 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 12 | Open Access | |
Notes | J. V. and A. B. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX. The Qu-Ant- EM microscope was partly funded by the Hercules fund from the Flemish Government. All authors acknowledge financial support from the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative. Reference No. 312483- ESTEEM2. J. V. acknowledges funding from the FWO under Project No. G.0044.13N.; esteem2jra2; esteem2jra3 ECASJO_; | Approved | Most recent IF: 8.462; 2015 IF: 7.512 | ||
Call Number | c:irua:129190 c:irua:129190UA @ admin @ c:irua:129190 | Serial | 3954 | ||
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Author | Jannis, D.; Müller-Caspary, K.; Béché, A.; Oelsner, A.; Verbeeck, J. | ||||
Title | Spectroscopic coincidence experiments in transmission electron microscopy | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
114 | Issue | 14 | Pages | 143101 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We demonstrate the feasibility of coincidence measurements on a conventional transmission electron microscope, revealing the temporal correlation between electron energy loss spectroscopy (EELS) and energy dispersive X-ray (EDX) spectroscopy events. We make use of a delay line detector with ps-range time resolution attached to a modified EELS spectrometer. We demonstrate that coincidence between both events, related to the excitation and deexcitation of atoms in a crystal, provides added information not present in the individual EELS or EDX spectra. In particular, the method provides EELS with a significantly suppressed or even removed background, overcoming the many difficulties with conventional parametric background fitting as it uses no assumptions on the shape of the background, requires no user input and does not suffer from counting noise originating from the background signal. This is highly attractive, especially when low concentrations of elements need to be detected in a matrix of other elements. |
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000464450200022 | Publication Date | 2019-04-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 18 | Open Access | OpenAccess |
Notes | Fonds Wetenschappelijk Onderzoek, G093417 ; Horizon 2020 Framework Programme, 823717 ESTEEM3 ; Helmholtz Association, VH-NG-1327 ; | Approved | Most recent IF: 3.411 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:159155 | Serial | 5168 | ||
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Author | Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J. | ||||
Title | Electron Bessel beam diffraction for precise and accurate nanoscale strain mapping | Type | A1 Journal article | ||
Year | 2019 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
114 | Issue | 24 | Pages | 243501 |
Keywords | A1 Journal article; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT) | ||||
Abstract | Strain has a strong effect on the properties of materials and the performance of electronic devices. Their ever shrinking size translates into a constant demand for accurate and precise measurement methods with a very high spatial resolution. In this regard, transmission electron microscopes are key instruments thanks to their ability to map strain with a subnanometer resolution. Here, we present a method to measure strain at the nanometer scale based on the diffraction of electron Bessel beams. We demonstrate that our method offers a strain sensitivity better than 2.5 × 10−4 and an accuracy of 1.5 × 10−3, competing with, or outperforming, the best existing methods with a simple and easy to use experimental setup. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000472599100019 | Publication Date | 2019-06-17 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 17 | Open Access | OpenAccess |
Notes | Deutsche Forschungsgemeinschaft, RO2057/12-2 ; Fonds Wetenschappelijk Onderzoek, G.0934.17N ; | Approved | Most recent IF: 3.411 | ||
Call Number | EMAT @ emat @UA @ admin @ c:irua:160119 | Serial | 5181 | ||
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Author | Verbeeck, J.; Tian, H.; Béché, A. | ||||
Title | A new way of producing electron vortex probes for STEM | Type | A1 Journal article | ||
Year | 2012 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
113 | Issue | Pages | 83-87 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A spiral holographic aperture is used in the condensor plane of a scanning transmission electron microscope to produce a focussed electron vortex probe carrying a topological charge of either −1, 0 or +1. The spiral aperture design has a major advantage over the previously used forked aperture in that the three beams with topological charge m=−1, 0, and 1 are not side by side in the specimen plane, but rather on top of each other, focussed at different heights. This allows us to have only one selected beam in focus on the sample while the others contribute only to a background signal. In this paper we describe the working principle as well as first experimental results demonstrating atomic resolution HAADF STEM images obtained with electron vortex probes. These results pave the way for atomic resolution magnetic information when combined with electron energy loss spectroscopy. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000300554400002 | Publication Date | 2011-10-31 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 62 | Open Access | |
Notes | J.V. wants to thank Miles Padgett for suggesting this setup and pointing to the relevant optics literature. Peter Schattschneider is acknowledged for in depth discussions on related topics. J.V acknowledges funding from the European Research Council under the 7th Framework Program (FP7), ERC Grant no. 46791-COUN-TATOMS and ERC Starting Grant no. 278510 VORTEX. The Qu-Ant-EM microscope is partially funded by the Hercules fund of the Flemish Government. ECASJO_; | Approved | Most recent IF: 2.843; 2012 IF: 2.470 | ||
Call Number | UA @ lucian @ c:irua:93624UA @ admin @ c:irua:93624 | Serial | 2336 | ||
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Author | Cooper, D.; Denneulin, T.; Barnes, J.-P.; Hartmann, J.-M.; Hutin, L.; Le Royer, C.; Béché, A.; Rouvière, J.-L. | ||||
Title | Strain mapping with nm-scale resolution for the silicon-on-insulator generation of semiconductor devices by advanced electron microscopy | Type | A1 Journal article | ||
Year | 2012 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
112 | Issue | Pages | 124505 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Strain engineering in the conduction channel is a cost effective method of boosting the performance in state-of-the-art semiconductor devices. However, given the small dimensions of these devices, it is difficult to quantitatively measure the strain with the required spatial resolution. Three different transmission electron microscopy techniques, high-angle annular dark field scanning transmission electron microscopy, dark field electron holography, and nanobeam electron diffraction have been applied to measure the strain in simple bulk and SOI calibration specimens. These techniques are then applied to different gate length SiGe SOI pFET devices in order to measure the strain in the conduction channel. For these devices, improved spatial resolution is required, and strain maps with spatial resolutions as good as 1 nm have been achieved. Finally, we discuss the relative advantages and disadvantages of using these three different techniques when used for strain measurement. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000312829400128 | Publication Date | 2012-12-19 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 14 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2012 IF: 3.794 | |||
Call Number | UA @ lucian @ c:irua:136433 | Serial | 4510 | ||
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Author | Clark, L.; Béché, A.; Guzzinati, G.; Lubk, A.; Mazilu, M.; Van Boxem, R.; Verbeeck, J. | ||||
Title | Exploiting lens aberrations to create electron-vortex beams | Type | A1 Journal article | ||
Year | 2013 | Publication | Physical review letters | Abbreviated Journal | Phys Rev Lett |
Volume ![]() |
111 | Issue | 6 | Pages | 064801-64805 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | A model for a new electron-vortex beam production method is proposed and experimentally demonstrated. The technique calls on the controlled manipulation of the degrees of freedom of the lens aberrations to achieve a helical phase front. These degrees of freedom are accessible by using the corrector lenses of a transmission electron microscope. The vortex beam is produced through a particular alignment of these lenses into a specifically designed astigmatic state and applying an annular aperture in the condenser plane. Experimental results are found to be in good agreement with simulations. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | New York, N.Y. | Editor | ||
Language | Wos | 000322921200009 | Publication Date | 2013-08-08 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0031-9007;1079-7114; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 8.462 | Times cited | 66 | Open Access | |
Notes | Vortex; Esteem2; Countatoms; FWO; Esteem2jra3 ECASJO; | Approved | Most recent IF: 8.462; 2013 IF: 7.728 | ||
Call Number | UA @ lucian @ c:irua:109340UA @ admin @ c:irua:109340 | Serial | 1148 | ||
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Author | Béché, A.; Rouvière, J.L.; Barnes, J.P.; Cooper, D. | ||||
Title | Dark field electron holography for strain measurement | Type | A1 Journal article | ||
Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
Volume ![]() |
111 | Issue | 3 | Pages | 227-238 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | Dark field electron holography is a new TEM-based technique for measuring strain with nanometer scale resolution. Here we present the procedure to align a transmission electron microscope and obtain dark field holograms as well as the theoretical background necessary to reconstruct strain maps from holograms. A series of experimental parameters such as biprism voltage, sample thickness, exposure time, tilt angle and choice of diffracted beam are then investigated on a silicon-germanium layer epitaxially embedded in a silicon matrix in order to obtain optimal dark field holograms over a large field of view with good spatial resolution and strain sensitivity. | ||||
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Publisher | Place of Publication | Amsterdam | Editor | ||
Language | Wos | 000288638200007 | Publication Date | 2010-12-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 2.843 | Times cited | 31 | Open Access | |
Notes | Approved | Most recent IF: 2.843; 2011 IF: 2.471 | |||
Call Number | UA @ lucian @ c:irua:136368 | Serial | 4496 | ||
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Author | Béché, A.; Goris, B.; Freitag, B.; Verbeeck, J. | ||||
Title | Development of a fast electromagnetic beam blanker for compressed sensing in scanning transmission electron microscopy | Type | A1 Journal article | ||
Year | 2016 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
108 | Issue | 108 | Pages | 093103 |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | The concept of compressed sensing was recently proposed to significantly reduce the electron dose in scanning transmission electron microscopy (STEM) while still maintaining the main features in the image. Here, an experimental setup based on an electromagnetic beam blanker placed in the condenser plane of a STEM is proposed. The beam blanker deflects the beam with a random pattern, while the scanning coils are moving the beam in the usual scan pattern. Experimental images at both the medium scale and high resolution are acquired and reconstructed based on a discrete cosine algorithm. The obtained results confirm that compressed sensing is highly attractive to limit beam damage in experimental STEM even though some remaining artifacts need to be resolved. | ||||
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Corporate Author | Thesis | ||||
Publisher | Place of Publication | Editor | |||
Language | Wos | 000375329200043 | Publication Date | 2016-03-01 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 40 | Open Access | |
Notes | A.B and J.V. acknowledge funding from the European Research Council under the 7th Framework Program (FP7), ERC Starting Grant No. 278510 VORTEX and under a contract for an Integrated Infrastructure Initiative (Reference No. 312483 ESTEEM2), from the GOA project SOLARPAINT and the POC project I13/009 from the University of Antwerp. B.G. acknowledges the Research Foundation Flanders (FWO Vlaanderen) for a postdoctoral research grant. The QuAnTem microscope was partially funded by the Hercules Foundation. We thank Zhaoliang Liao from the Mesa+ laboratory at the University of Twente for the perovskite test sample.; esteem2jra3 ECASJO; | Approved | Most recent IF: 3.411 | ||
Call Number | c:irua:131895 c:irua:131895UA @ admin @ c:irua:131895 | Serial | 4023 | ||
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Author | Jones, E.; Cooper, D.; Rouvière, J.-L.; Béché, A.; Azize, M.; Palacios, T.; Gradecak, S. | ||||
Title | Towards rapid nanoscale measurement of strain in III-nitride heterostructures | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied Physics Letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
103 | Issue | Pages | 231904 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | We report the structural and compositional nanoscale characterization of InAlN/GaN nanoribbon-structured high electron mobility transistors (HEMTs) through the use of geometric phase analysis (GPA) and nanobeam electron diffraction (NBED). The strain distribution in the HEMT layer is quantified and compared to the expected strain profile for the nominal structure predicted by finite element analysis (FEA). Using the experimental strain results, the actual structure is determined and used to modify the FEA model. The improved fit of the model demonstrates that GPA and NBED provide a powerful platform for routine and rapid characterization of strain in III-V semiconducting device systems leading to insights into device evolution during processing and future device optimization. | ||||
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Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000328634900025 | Publication Date | 2013-12-03 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 6 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | |||
Call Number | UA @ lucian @ c:irua:136443 | Serial | 4513 | ||
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Author | Rouvière, J.-L.; Béché, A.; Martin, Y.; Denneulin, T.; Cooper, D. | ||||
Title | Improved strain precision with high spatial resolution using nanobeam precession electron diffraction | Type | A1 Journal article | ||
Year | 2013 | Publication | Applied physics letters | Abbreviated Journal | Appl Phys Lett |
Volume ![]() |
103 | Issue | Pages | 241913 | |
Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
Abstract | NanoBeam Electron Diffraction is a simple and efficient technique to measure strain in nanostructures. Here, we show that improved results can be obtained by precessing the electron beam while maintaining a few nanometer probe size, i.e., by doing Nanobeam Precession Electron Diffraction (N-PED). The precession of the beam makes the diffraction spots more uniform and numerous, making N-PED more robust and precise. In N-PED, smaller probe size and better precision are achieved by having diffraction disks instead of diffraction dots. Precision in the strain measurement better than 2 × 10−4 is obtained with a probe size approaching 1 nm in diameter. | ||||
Address | |||||
Corporate Author | Thesis | ||||
Publisher | American Institute of Physics | Place of Publication | New York, N.Y. | Editor | |
Language | Wos | 000328706500031 | Publication Date | 2013-12-14 | |
Series Editor | Series Title | Abbreviated Series Title | |||
Series Volume | Series Issue | Edition | |||
ISSN | 0003-6951; 1077-3118 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
Impact Factor | 3.411 | Times cited | 53 | Open Access | |
Notes | Approved | Most recent IF: 3.411; 2013 IF: 3.515 | |||
Call Number | UA @ lucian @ c:irua:136442 | Serial | 4502 | ||
Permanent link to this record |