NANOlab Center of Excellence literature database -- Query Results

	NANOlab Center of Excellence literature database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	121–150 of 153 records found matching your query (RSS):

Select All Deselect All

<< 1 2 3 4 5 6 >>

List View

Citations

Details

	Records
	Author	Heidari Mezerji, H.; van den Broek, W.; Bals, S.
	Title	A practical method to determine the effective resolution in incoherent experimental electron tomography			Type	A1 Journal article
	Year	2011	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	111	Issue	5	Pages	330-336
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	It is not straightforward to determine resolution for a 3D reconstruction when performing an electron tomography experiment. Different contributions such as missing wedge and misalignment add up and often influence the final resolution in an anisotropic manner. The conventional resolution measures can not be used for all of the reconstruction techniques, especially for iterative techniques which are more commonly used for electron tomography in materials science. Here we define a quantitative resolution measure that determines the resolution in three orthogonal directions of the reconstruction. As an application we use this measure to determine the optimum number of simultaneous iterative reconstruction technique (SIRT) iterations to reconstruct the gold nanoparticles, based on a high angle annular dark field STEM (HAADF-STEM) tilt series.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000289396900005	Publication Date	2011-01-24
	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	26	Open Access
	Notes	Esteem 026019; Fwo			Approved	Most recent IF: 2.843; 2011 IF: 2.471
	Call Number	UA @ lucian @ c:irua:87606			Serial	2688
Permanent link to this record



	Author	Wang, A.; Van Aert, S.; Goos, P.; van Dyck, D.
	Title	Precision of three-dimensional atomic scale measurements from HRTEM images : what are the limits?			Type	A1 Journal article
	Year	2012	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	114	Issue		Pages	20-30
	Keywords	A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab
	Abstract	In this paper, we investigate to what extent high resolution transmission electron microscopy images can be used to measure the mass, in terms of thickness, and surface profile, corresponding to the defocus offset, of an object at the atomic scale. Therefore, we derive an expression for the statistical precision with which these object parameters can be estimated in a quantitative analysis. Evaluating this expression as a function of the microscope settings allows us to derive the optimal microscope design. Acquiring three-dimensional structure information in terms of thickness turns out to be much more difficult than obtaining two-dimensional information on the projected atom column positions. The attainable precision is found to be more strongly affected by processes influencing the image contrast, such as phonon scattering, than by the specific choice of microscope settings. For a realistic incident electron dose, it is expected that atom columns can be distinguished with single atom sensitivity up to a thickness of the order of the extinction distance. A comparable thickness limit is determined to measure surface steps of one atom. An increase of the electron dose shifts the limiting thickness upward due to an increase in the signal-to-noise ratio.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000301954300003	Publication Date	2012-01-06
	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	5	Open Access
	Notes	Fwo			Approved	Most recent IF: 2.843; 2012 IF: 2.470
	Call Number	UA @ lucian @ c:irua:94116			Serial	2692
Permanent link to this record



	Author	Chen, D.; Goris, B.; Bleichrodt, F.; Heidari Mezerji, H.; Bals, S.; Batenburg, K.J.; de With, G.; Friedrich, H.
	Title	The properties of SIRT, TVM, and DART for 3D imaging of tubular domains in nanocomposite thin-films and sections			Type	A1 Journal article
	Year	2014	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	147	Issue		Pages	137-148
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In electron tomography, the fidelity of the 3D reconstruction strongly depends on the employed reconstruction algorithm. In this paper, the properties of SIRT, TVM and DART reconstructions are studied with respect to having only a limited number of electrons available for imaging and applying different angular sampling schemes. A well-defined realistic model is generated, which consists of tubular domains within a matrix having slab-geometry. Subsequently, the electron tomography workflow is simulated from calculated tilt-series over experimental effects to reconstruction. In comparison with the model, the fidelity of each reconstruction method is evaluated qualitatively and quantitatively based on global and local edge profiles and resolvable distance between particles. Results show that the performance of all reconstruction methods declines with the total electron dose. Overall, SIRT algorithm is the most stable method and insensitive to changes in angular sampling. TVM algorithm yields significantly sharper edges in the reconstruction, but the edge positions are strongly influenced by the tilt scheme and the tubular objects become thinned. The DART algorithm markedly suppresses the elongation artifacts along the beam direction and moreover segments the reconstruction which can be considered a significant advantage for quantification. Finally, no advantage of TVM and DART to deal better with fewer projections was observed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000343157400015	Publication Date	2014-08-19
	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	42	Open Access	OpenAccess
	Notes	Fwo			Approved	Most recent IF: 2.843; 2014 IF: 2.436
	Call Number	UA @ lucian @ c:irua:119073			Serial	2729
Permanent link to this record



	Author	Bertoni, G.; Beyers, E.; Verbeeck, J.; Mertens, M.; Cool, P.; Vansant, E.F.; Van Tendeloo, G.
	Title	Quantification of crystalline and amorphous content in porous TiO₂ samples from electron energy loss spectroscopy			Type	A1 Journal article
	Year	2006	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	106	Issue	7	Pages	630-635
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Laboratory of adsorption and catalysis (LADCA)
	Abstract	We present an efficient method for the quantification of crystalline versus amorphous phase content in mesoporous materials, making use of electron energy loss spectroscopy. The method is based on fitting a superposition of core-loss edges using the maximum likelihood method with measured reference spectra. We apply the method to mesoporous TiO2 samples. We show that the absolute amount of the crystalline phase can be determined with an accuracy below 5%. This method takes also the amorphous phase into account, where standard X-ray diffraction is only quantitative for crystalline phases and not for amorphous phase. (c) 2006 Elsevier B.V.. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000238479300011	Publication Date	2006-04-28
	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	83	Open Access
	Notes	Iap-V; Goa-2005; Fwo			Approved	Most recent IF: 2.843; 2006 IF: 1.706
	Call Number	UA @ lucian @ c:irua:58823UA @ admin @ c:irua:58823			Serial	2741
Permanent link to this record



	Author	Van Aert, S.; Verbeeck, J.; Erni, R.; Bals, S.; Luysberg, M.; van Dyck, D.; Van Tendeloo, G.
	Title	Quantitative atomic resolution mapping using high-angle annular dark field scanning transmission electron microscopy			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	10	Pages	1236-1244
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	A model-based method is proposed to relatively quantify the chemical composition of atomic columns using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. The method is based on a quantification of the total intensity of the scattered electrons for the individual atomic columns using statistical parameter estimation theory. In order to apply this theory, a model is required describing the image contrast of the HAADF STEM images. Therefore, a simple, effective incoherent model has been assumed which takes the probe intensity profile into account. The scattered intensities can then be estimated by fitting this model to an experimental HAADF STEM image. These estimates are used as a performance measure to distinguish between different atomic column types and to identify the nature of unknown columns with good accuracy and precision using statistical hypothesis testing. The reliability of the method is supported by means of simulated HAADF STEM images as well as a combination of experimental images and electron energy-loss spectra. It is experimentally shown that statistically meaningful information on the composition of individual columns can be obtained even if the difference in averaged atomic number Z is only 3. Using this method, quantitative mapping at atomic resolution using HAADF STEM images only has become possible without the need of simultaneously recorded electron energy loss spectra.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000270015200004	Publication Date	2009-05-28
	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	166	Open Access
	Notes	Fwo; Esteem 026019			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:78585UA @ admin @ c:irua:78585			Serial	2748
Permanent link to this record



	Author	Schattschneider, P.; Verbeeck, J.; Hamon, A.L.
	Title	Real space maps of atomic transitions			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	7	Pages	781-787
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Considering the rapid technical development of transmission electron microscopes, we investigate the possibility to map electronic transitions in real space on the atomic scale. To this purpose, we analyse the information carried by the scatterer's initial and final state wave functions and the role of the different atomic transition channels for the inelastic scattering cross section. It is shown that the change in the magnetic quantum number in the transition can be mapped. Two experimental set-ups are proposed, one blocking half the diffraction plane, the other one using a cylinder lens for imaging. Both methods break the conventional circular symmetry in the electron microscope making it possible to detect the handedness of electronic transitions as an asymmetry in the image intensity. This finding is of important for atomic resolution energy-loss magnetic chiral dichroism (EMCD), allowing to obtain the magnetic moments of single atoms.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000266787900002	Publication Date	2009-03-01
	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	10	Open Access
	Notes	J.V. acknowledges the FWO-Vlaanderen for support (contract no. G.0147.06) and the European Union under the Framework 6 program under a contract for an Integrated Infrastructure Initiative. Reference 026019 ESTEEM.			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:77360UA @ admin @ c:irua:77360			Serial	2829
Permanent link to this record



	Author	Schattschneider, P.; Ennen, I.; Stoger-Pollach, M.; Verbeeck, J.; Mauchamp, V.; Jaouen, M.
	Title	Real space maps of magnetic moments on the atomic scale: theory and feasibility			Type	A1 Journal article
	Year	2010	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	110	Issue	8	Pages	1038-1041
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The recently discovered EMCD technique (energy loss magnetic chiral dichroism) can detect atom specific magnetic moments with nanometer resolution, exploiting the spin selectivity of electronic transitions in energy loss spectroscopy. Yet, direct imaging of magnetic moments on the atomic scale is not possible. In this paper we present an extension of EMCD that can overcome this limit. As a model system we chose bcc Fe. We present image simulations of the L3 white line signal, based on the kinetic equation for the density matrix of the 200 kV probe electron. With actual progress in instrumentation (high brightness sources, aberration corrected lenses) this technique should allow direct imaging of spin moments on the atomic scale.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000281216600016	Publication Date	2009-12-07
	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	10	Open Access
	Notes	---			Approved	Most recent IF: 2.843; 2010 IF: 2.063
	Call Number	UA @ lucian @ c:irua:84439UA @ admin @ c:irua:84439			Serial	2830
Permanent link to this record



	Author	Zhang, X.B.; Zhang, X.F.; Amelinckx, S.; Van Tendeloo, G.; van Landuyt, J.
	Title	The reciprocal space of carbon tubes: a detailed interpretation of the electron diffraction effects			Type	A1 Journal article
	Year	1994	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	54	Issue		Pages	237-249
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	A1994PA59800016	Publication Date	2002-10-18
	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	2.436	Times cited	59	Open Access
	Notes				Approved
	Call Number	UA @ lucian @ c:irua:10006			Serial	2844
Permanent link to this record



	Author	Müller, K.; Schowalter, M.; Jansen, J.; Tsuda, K.; Titantah, J.; Lamoen, D.; Rosenauer, A.
	Title	Refinement of the 200 structure factor for GaAs using parallel and convergent beam electron nanodiffraction data			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	7	Pages	802-814
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We present a new method to measure structure factors from electron spot diffraction patterns recorded under almost parallel illumination in transmission electron microscopes. Bloch wave refinement routines have been developed to refine the crystal thickness, its orientation and structure factors by comparison of experimentally recorded and calculated intensities. Our method requires a modicum of computational effort, making it suitable for contemporary personal computers. Frozen lattice and Bloch wave simulations of GaAs diffraction patterns are used to derive optimised experimental conditions. Systematic errors are estimated from the application of the method to simulated diffraction patterns and rules for the recognition of physically reasonable initial refinement conditions are derived. The method is applied to the measurement of the 200 structure factor for GaAs. We found that the influence of inelastically scattered electrons is negligible. Additionally, we measured the 200 structure factor from zero loss filtered two-dimensional convergent beam electron diffraction patterns. The precision of both methods is found to be comparable and the results agree well with each other. A deviation of more than 20% from isolated atom scattering data is observed, whereas close agreement is found with structure factors obtained from density functional theory [A. Rosenauer, M. Schowalter, F. Glas, D. Lamoen, Phys. Rev. B 72 (2005), 085326-1], which account for the redistribution of electrons due to chemical bonding via modified atomic scattering amplitudes.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000266787900005	Publication Date	2009-03-23
	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	8	Open Access
	Notes	Fwo; G.0425.05; Esteem; Ant 200611271505			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:77361			Serial	2856
Permanent link to this record



	Author	Amelinckx, S.; Milat, O.; Van Tendeloo, G.
	Title	Selective imaging of sublattices in complex structures			Type	A1 Journal article
	Year	1993	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	51	Issue		Pages	90-108
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	A1993LN79100010	Publication Date	2002-10-18
	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	2.436	Times cited	8	Open Access
	Notes				Approved	CHEMISTRY, PHYSICAL 54/144 Q2 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 9/35 Q2 #
	Call Number	UA @ lucian @ c:irua:6835			Serial	2964
Permanent link to this record



	Author	Milat, O.; Van Tendeloo, G.; Amelinckx, S.
	Title	Selective imaging of the “substructures” in incommensurately modulated intergrowth crystal structures			Type	A1 Journal article
	Year	1992	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	41	Issue		Pages	65-76
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	A1992HX68100006	Publication Date	2002-10-18
	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	2.436	Times cited	5	Open Access
	Notes				Approved	MATERIALS SCIENCE, MULTIDISCIPLINARY 96/271 Q2 #
	Call Number	UA @ lucian @ c:irua:4437			Serial	2966
Permanent link to this record



	Author	Zhang, X.F.; Zhang, X.B.; Bernaerts, D.; Van Tendeloo, G.; Amelinckx, S.; van Landuyt, J.; Werner, H.
	Title	A simple preparation method for air-sensitive specimens for transmission electron microscopy demonstrated by Rb₆C₆₀			Type	A1 Journal article
	Year	1994	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	55	Issue		Pages	25-30
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In this paper a particularly simple but efficient method is presented by which samples of alkali-doped C-60 materials or other air-sensitive materials can be prepared and transferred into a transmission electron microscope for direct observations and investigations. Flexible, transparent glove bags are used which are filled to a slight overpressure with dry nitrogen. Under this protective atmosphere, the air-sensitive sample is mounted in the specimen holder and inserted in the vacuum of the electron microscope. Rb6C60 which is prepared and transferred into the microscope in this way has been investigated by transmission electron microscopy (TEM). The results confirm the bcc structure and especially the location of the rubidium atoms.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	A1994PE30800005	Publication Date	2002-10-18
	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	2.436	Times cited	2	Open Access
	Notes				Approved	CHEMISTRY, PHYSICAL 77/144 Q3 # MATHEMATICS, INTERDISCIPLINARY 19/101 Q1 # PHYSICS, ATOMIC, MOLECULAR & CHEMICAL 17/35 Q2 #
	Call Number	UA @ lucian @ c:irua:10007			Serial	3002
Permanent link to this record



	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
Permanent link to this record



	Author	Van Tendeloo, G.; Amelinckx, S.; Muto, S.; Verheijen, M.A.; van Loosdrecht, P.H.M.; Meijer, G.
	Title	Structures and phase transitions in C₆₀ and C₇₀ fullerites			Type	A1 Journal article
	Year	1993	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	51	Issue		Pages	168-188
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	A1993LN79100017	Publication Date	2002-10-18
	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	2.436	Times cited	17	Open Access
	Notes				Approved	PHYSICS, APPLIED 28/145 Q1 #
	Call Number	UA @ lucian @ c:irua:6836			Serial	3319
Permanent link to this record



	Author	Ke, X.; Bals, S.; Romo Negreira, A.; Hantschel, T.; Bender, H.; Van Tendeloo, G.
	Title	TEM sample preparation by FIB for carbon nanotube interconnects			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	11	Pages	1353-1359
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000270765800006	Publication Date	2009-07-11
	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	21	Open Access
	Notes	Esteem 026019; Iap			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:79074			Serial	3485
Permanent link to this record



	Author	van Landuyt, J.
	Title	The evolution of HVEM application in antwerp			Type	A1 Journal article
	Year	1991	Publication	Ultramicroscopy T2 – 2nd Osaka International Symp.on High-Voltage Electron Microscopy : New Directions and Future Aspects of High Voltage Electron Microscopy, November 8-10, 1990, Osaka University, Osaka, Japan	Abbreviated Journal	Ultramicroscopy
	Volume	39	Issue	1-4	Pages	287-298
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The evolution of the use of the 1250 keV high-voltage electron microscope in Antwerp is sketched by illustrating a non-exhaustive set of examples in various fields. One of the main present fields of application gets some more attention, i.e. the defect studies as produced by processing steps in microelectronic devices: (i) strain-induced dislocations at the edges of various device isolation interlayers, (ii) morphologies resulting from high-energy ion implantation creating buried layers for silicon on insulator (SOI) and other implantation technologies.
	Address
	Corporate Author				Thesis
	Publisher	Elsevier	Place of Publication	Amsterdam	Editor
	Language		Wos	A1991GY23100034	Publication Date	2002-10-18
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN	0304-3991;	ISBN		Additional Links	UA library record; WoS full record
	Impact Factor	2.436	Times cited		Open Access
	Notes				Approved	PHYSICS, APPLIED 47/145 Q2 #
	Call Number	UA @ lucian @ c:irua:95973			Serial	3579
Permanent link to this record



	Author	Verbeeck, J.; Bertoni, G.; Schattschneider, P.
	Title	The Fresnel effect of a defocused biprism on the fringes in inelastic holography			Type	A1 Journal article
	Year	2008	Publication	Ultramicroscopy T2 – 16th International Microscopy Congress, SEP 03-08, 2006, Sapporo, JAPAN	Abbreviated Journal	Ultramicroscopy
	Volume	108	Issue	3	Pages	263-269
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	We present energy filtered holography experiments on a thin foil of Al. By propagating the reduced density matrix of the probe electron through the microscope, we quantitatively predict the fringe contrast as a function of energy loss. Fringe contrast simulations include the effect of Fresnel fringes created at the edges of the defocused biprism, the effect of partial coherence in combination with inelastic scattering, and the effect of a finite energy distribution of the incoming beam. (c) 2007 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000253389100011	Publication Date	2007-11-02
	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	2.843	Times cited	15	Open Access
	Notes	Fwo G.0147.06; Esteem 026019			Approved	Most recent IF: 2.843; 2008 IF: 2.629
	Call Number	UA @ lucian @ c:irua:104035			Serial	3582
Permanent link to this record



	Author	Schattschneider, P.; Verbeeck, J.
	Title	Theory of free electron vortices			Type	A1 Journal article
	Year	2011	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	111	Issue	9/10	Pages	1461-1468
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	The recent creation of electron vortex beams and their first practical application motivates a better understanding of their properties. Here, we develop the theory of free electron vortices with quantized angular momentum, based on solutions of the Schrödinger equation for cylindrical boundary conditions. The principle of transformation of a plane wave into vortices with quantized angular momentum, their paraxial propagation through round magnetic lenses, and the effect of partial coherence are discussed.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000300461200002	Publication Date	2011-07-26
	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	57	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 2.843; 2011 IF: 2.471
	Call Number	UA @ lucian @ c:irua:91882			Serial	3617
Permanent link to this record



	Author	van den Broek, W.; Van Aert, S.; Goos, P.; van Dyck, D.
	Title	Throughput maximization of particle radius measurements by balancing size and current of the electron probe			Type	A1 Journal article
	Year	2011	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	111	Issue	7	Pages	940-947
	Keywords	A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT); Vision lab
	Abstract	In thispaperweinvestigatewhichprobesizemaximizesthethroughputwhenmeasuringtheradiusof nanoparticlesinhighangleannulardarkfieldscanningtransmissionelectronmicroscopy(HAADFSTEM). The sizeandthecorrespondingcurrentoftheelectronprobedeterminetheprecisionoftheestimateofa particlesradius.Maximizingthroughputmeansthatamaximumnumberofparticlesshouldbeimaged withinagiventimeframe,sothataprespecifiedprecisionisattained.WeshowthatBayesianstatistical experimentaldesignisaveryusefulapproachtodeterminetheoptimalprobesizeusingacertainamount of priorknowledgeaboutthesample.Thedependenceoftheoptimalprobesizeonthedetectorgeometry and thediameter,variabilityandatomicnumberoftheparticlesisinvestigated.Anexpressionforthe optimalprobesizeintheabsenceofanykindofpriorknowledgeaboutthespecimenisderivedaswell.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000300461000026	Publication Date	2010-11-25
	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	7	Open Access
	Notes				Approved	Most recent IF: 2.843; 2011 IF: 2.471
	Call Number	UA @ lucian @ c:irua:89657			Serial	3659
Permanent link to this record



	Author	van den Broek, W.; Verbeeck, J.; Schryvers, D.; de Backer, S.; Scheunders, P.
	Title	Tomographic spectroscopic imaging; an experimental proof of concept			Type	A1 Journal article
	Year	2009	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	109	Issue	4	Pages	296-303
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000265345400003	Publication Date	2008-12-10
	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	1	Open Access
	Notes	Esteem 026019			Approved	Most recent IF: 2.843; 2009 IF: 2.067
	Call Number	UA @ lucian @ c:irua:77271			Serial	3671
Permanent link to this record



	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.
	Address
	Corporate Author				Thesis
	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
Permanent link to this record



	Author	Vatanparast, M.; Egoavil, R.; Reenaas, T.W.; Verbeeck, J.; Holmestad, R.; Vullum, P.E.
	Title	Bandgap measurement of high refractive index materials by off-axis EELS			Type	A1 Journal article
	Year	2017	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	182	Issue		Pages	92-98
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	In the present work Cs aberration corrected and monochromated scanning transmission electron microscopy electron energy loss spectroscopy (STEM-EELS) has been used to explore experimental setups that allow bandgaps of high refractive index materials to be determined. Semi-convergence and collection angles in the mu rad range were combined with off-axis or dark field EELS to avoid relativistic losses and guided light modes in the low loss range to contribute to the acquired EEL spectra. Off-axis EELS further supressed the zero loss peak and the tail of the zero loss peak. The bandgap of several GaAs-based materials were successfully determined by simple regression analyses of the background subtracted EEL spectra. The presented set-up does not require that the acceleration voltage is set to below the. Cerenkov limit and can be applied over the entire acceleration voltage range of modern TEMs and for a wide range of specimen thicknesses. (C) 2017 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000413436500013	Publication Date	2017-06-21
	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	3	Open Access	Not_Open_Access
	Notes	; The authors would like to thank Professor Shu Min Wang and Mahdad Sadeghi at the Nanofabrication Laboratory at Chalmers University, Sweden for providing the samples. The Norwegian Research Council is acknowledged for funding the HighQ-IB project under contract no. 10415201. M.V. and T.W.R. acknowledge funding from the EEA Financial Mechanism 2009-2014 under the project contract no 23SEE/30.06.2014. 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) through the system of transnational access. R.E. and J.V. acknowledge funding from GOA project “Solarpaint” of the University of Antwerp. ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:146639UA @ admin @ c:irua:146639			Serial	4778
Permanent link to this record



	Author	Grieb, T.; Krause, F.F.; Mahr, C.; Zillmann, D.; Müller-Caspary, K.; Schowalter, M.; Rosenauer, A.
	Title	Optimization of NBED simulations for disc-detection measurements			Type	A1 Journal article
	Year	2017	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	181	Issue		Pages	50-60
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Nano-beam electron diffraction (NBED) is a method which can be applied to measure lattice strain and polarisation fields in strained layer heterostructures and transistors. To investigate precision, accuracy and spatial resolution of such measurements in dependence of properties of the specimen as well as electron optical parameters, simulations of NBED patterns are required which allow to predict the result of common disc-detection algorithms. In this paper we demonstrate by focusing on the detection of the central disc in crystalline silicon that such simulations require to take several experimental characteristics into account in order to obtain results which are comparable to those from experimental NBED patterns. These experimental characteristics are the background intensity, the presence of Poisson noise caused by electron statistics and blurring caused by inelastic scattering and by the transfer quality of the microscope camera. By means of these optimized simulations, different effects of specimen properties on disc detection – such as strain, surface morphology and compositional changes on the nanometer scale – are investigated and discussed in the context of misinterpretation in experimental NBED evaluations. It is shown that changes in surface morphology and chemical composition lead to measured shifts of the central disc in the NBED pattern of tens to hundreds of grad. These shifts are of the same order of magnitude or even larger than shifts that could be caused by an electric polarisation field in the range of MV/cm. (C) 2017 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000411170800006	Publication Date	2017-05-03
	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	6	Open Access	Not_Open_Access
	Notes	; This work was supported by the German Research Foundation (DFG) under Contract No. R02057/11-1, R02057/4-2 and MU3660/1-1. ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:146725			Serial	4792
Permanent link to this record



	Author	Alania, M.; Lobato Hoyos, I.P.; Van Aert, S.
	Title	Frozen lattice and absorptive model for high angle annular dark field scanning transmission electron microscopy : a comparison study in terms of integrated intensity and atomic column position measurement			Type	A1 Journal article
	Year	2018	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	184	Issue	A	Pages	188-198
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('In this paper, both the frozen lattice (FL) and the absorptive potential (AP) approximation models are compared in terms of the integrated intensity and the precision with which atomic columns can be located from an image acquired using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM). The comparison is made for atoms of Cu, Ag, and Au. The integrated intensity is computed for both an isolated atomic column and an atomic column inside an FCC structure. The precision has been computed using the so-called Cramer-Rao Lower Bound (CRLB), which provides a theoretical lower bound on the variance with which parameters can be estimated. It is shown that the AP model results into accurate measurements for the integrated intensity only for small detector ranges under relatively low angles and for small thicknesses. In terms of the attainable precision, both methods show similar results indicating picometer range precision under realistic experimental conditions. (C) 2017 Elsevier B.V. All rights reserved.'));
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000415650200022	Publication Date	2017-09-12
	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		Open Access	OpenAccess
	Notes	; The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0374.13N, G.0369.15N, and G.0368.15N). A. Rosenauer is acknowledged for providing the STEMsim program. ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:147658			Serial	4877
Permanent link to this record



	Author	Grieb, T.; Tewes, M.; Schowalter, M.; Müller-Caspary, K.; Krause, F.F.; Mehrtens, T.; Hartmann, J.-M.; Rosenauer, A.
	Title	Quantitative HAADF STEM of SiGe in presence of amorphous surface layers from FIB preparation			Type	A1 Journal article
	Year	2018	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	184	Issue	B	Pages	29-36
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	<script type='text/javascript'>document.write(unpmarked('The chemical composition of four Si1-xGex layers grown on silicon was determined from quantitative scanning transmission electron microscopy (STEM). The chemical analysis was performed by a comparison of the high-angle annular dark field (HAADF) intensity with multislice simulations. It could be shown that amorphous surface layers originating from the preparation process by focused-ion beam (FIB) at 30 kV have a strong influence on the quantification: the local specimen thickness is overestimated by approximately a factor of two, and the germanium concentration is substantially underestimated. By means of simulations, the effect of amorphous surface layers on the HAADF intensity of crystalline silicon and germanium is investigated. Based on these simulations, a method is developed to analyze the experimental HAADF-STEM images by taking the influence of the amorphous layers into account which is done by a reduction of the intensities by multiplication with a constant factor. This suggested modified HAADF analysis gives germanium concentrations which are in agreement with the nominal values. The same TEM lamella was treated with low-voltage ion milling which removed the amorphous surface layers completely. The results from subsequent quantitative HAADF analyses are in agreement with the nominal concentrations which validates the applicability of the used frozen-lattice based multislice simulations to describe the HAADF scattering of Si1-xGex in STEM. (C) 2017 Elsevier B.V. All rights reserved.'));
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000417779800004	Publication Date	2017-10-14
	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	7	Open Access	Not_Open_Access
	Notes	; This work was supported by the German Research Foundation (DFG) under Contract No. RO2057/11-1. ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:148500			Serial	4893
Permanent link to this record



	Author	Korneychuk, S.; Partoens, B.; Guzzinati, G.; Ramaneti, R.; Derluyn, J.; Haenen, K.; Verbeeck, J.
	Title	Exploring possibilities of band gap measurement with off-axis EELS in TEM			Type	A1 Journal article
	Year	2018	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	189	Issue	189	Pages	76-84
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT); Condensed Matter Theory (CMT)
	Abstract	A technique to measure the band gap of dielectric materials with high refractive index by means of energy electron loss spectroscopy (EELS) is presented. The technique relies on the use of a circular (Bessel) aperture and suppresses Cherenkov losses and surface-guided light modes by enforcing a momentum transfer selection. The technique also strongly suppresses the elastic zero loss peak, making the acquisition, interpretation and signal to noise ratio of low loss spectra considerably better, especially for excitations in the first few eV of the EELS spectrum. Simulations of the low loss inelastic electron scattering probabilities demonstrate the beneficial influence of the Bessel aperture in this setup even for high accelerating voltages. The importance of selecting the optimal experimental convergence and collection angles is highlighted. The effect of the created off-axis acquisition conditions on the selection of the transitions from valence to conduction bands is discussed in detail on a simplified isotropic two band model. This opens the opportunity for deliberately selecting certain transitions by carefully tuning the microscope parameters. The suggested approach is experimentally demonstrated and provides good signal to noise ratio and interpretable band gap signals on reference samples of diamond, GaN and AlN while offering spatial resolution in the nm range. (C) 2018 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000432868500008	Publication Date	2018-03-29
	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	7	Open Access	OpenAccess
	Notes	; S.K., B.P. and J.V. acknowledge funding from the “Geconcentreerde Onderzoekacties” (GOA) project “Solarpaint” of the University of Antwerp. S.K. and J.V. also acknowledge the FWO-Vlaanderen for financial support under contract G.0044.13N 'Charge ordering'. Financial support via the Methusalem “NANO” network is acknowledged. GG acknowledges support from a postdoctoral fellowship grant from the Fonds Wetenschappelijk Onderzoek-Vlaanderen (FWO). ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:151472UA @ admin @ c:irua:151472			Serial	5026
Permanent link to this record



	Author	Grieb, T.; Krause, F.F.; Schowalter, M.; Zillmann, D.; Sellin, R.; Müller-Caspary, K.; Mahr, C.; Mehrtens, T.; Bimberg, D.; Rosenauer, A.
	Title	Strain analysis from nano-beam electron diffraction : influence of specimen tilt and beam convergence			Type	A1 Journal article
	Year	2018	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	190	Issue	190	Pages	45-57
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Strain analyses from experimental series of nano-beam electron diffraction (NBED) patterns in scanning transmission electron microscopy are performed for different specimen tilts. Simulations of NBED series are presented for which strain analysis gives results that are in accordance with experiment. This consequently allows to study the relation between measured strain and actual underlying strain. A two-tilt method which can be seen as lowest-order electron beam precession is suggested and experimentally implemented. Strain determination from NBED series with increasing beam convergence is performed in combination with the experimental realization of a probe-forming aperture with a cross inside. It is shown that using standard evaluation techniques, the influence of beam convergence on spatial resolution is lower than the influence of sharp rings around the diffraction disc which occur at interfaces and which are caused by the tails of the intensity distribution of the electron probe. (C) 2018 Elsevier B.V. All rights reserved.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication	Amsterdam	Editor
	Language		Wos	000432868800006	Publication Date	2018-04-12
	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	1	Open Access	OpenAccess
	Notes	; This work was supported by the German Research Foundation (DFG) under Contracts RO2057/11-1 and RO2057/12-1. ;			Approved	Most recent IF: 2.843
	Call Number	UA @ lucian @ c:irua:151454			Serial	5041
Permanent link to this record



	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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000465021000013	Publication Date	2018-12-30
	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	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
Permanent link to this record



	Author	Susi, T.; Madsen, J.; Ludacka, U.; Mortensen, J.J.; Pennycook, T.J.; Lee, Z.; Kotakoski, J.; Kaiser, U.; Meyer, J.C.
	Title	Efficient first principles simulation of electron scattering factors for transmission electron microscopy			Type	A1 Journal article
	Year	2019	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	197	Issue	197	Pages	16-22
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Electron microscopy is a powerful tool for studying the properties of materials down to their atomic structure. In many cases, the quantitative interpretation of images requires simulations based on atomistic structure models. These typically use the independent atom approximation that neglects bonding effects, which may, however, be measurable and of physical interest. Since all electrons and the nuclear cores contribute to the scattering potential, simulations that go beyond this approximation have relied on computationally highly demanding all-electron calculations. Here, we describe a new method to generate ab initio electrostatic potentials when describing the core electrons by projector functions. Combined with an interface to quantitative image simulations, this implementation enables an easy and fast means to model electron scattering. We compare simulated transmission electron microscopy images and diffraction patterns to experimental data, showing an accuracy equivalent to earlier all-electron calculations at a much lower computational cost.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000456311700003	Publication Date	2018-11-12
	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	3	Open Access
	Notes				Approved	Most recent IF: 2.843
	Call Number	UA @ admin @ c:irua:165938			Serial	6296
Permanent link to this record



	Author	Pennycook, T.J.; Martinez, G.T.; Nellist, P.D.; Meyer, J.C.
	Title	High dose efficiency atomic resolution imaging via electron ptychography			Type	A1 Journal article
	Year	2019	Publication	Ultramicroscopy	Abbreviated Journal	Ultramicroscopy
	Volume	196	Issue	196	Pages	131-135
	Keywords	A1 Journal article; Electron microscopy for materials research (EMAT)
	Abstract	Radiation damage places a fundamental limitation on the ability of microscopy to resolve many types of materials at high resolution. Here we evaluate the dose efficiency of phase contrast imaging with electron ptychography. The method is found to be far more resilient to temporal incoherence than conventional and spherical aberration optimized phase contrast imaging, resulting in significantly greater clarity at a given dose. This robustness is explained by the presence of achromatic lines in the four dimensional ptychographic dataset.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos	000451180800018	Publication Date	2018-10-18
	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	1	Open Access
	Notes				Approved	Most recent IF: 2.843
	Call Number	UA @ admin @ c:irua:165939			Serial	6301
Permanent link to this record