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Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Density-functional theory calculations of the electron energy-loss near-edge structure of Li-intercalated graphite Type A1 Journal article
Year 2009 Publication Carbon Abbreviated Journal Carbon
Volume 47 Issue 10 Pages 2501-2510
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We have studied the structural and electronic properties of lithium-intercalated graphite (LIG) for various Li content. Atomic relaxation shows that Li above the center of the carbon hexagon in a AAAA stacked graphite is the only stable Li configuration in stage 1 intercalated graphite. Lithium and Carbon 1s energy-loss near-edge structure (ELNES) calculations are performed on the Li-intercalated graphite using the core-excited density-functional theory formulation. Several features of the Li 1s ELNES are correlated with reported experimental features. The ELNES spectra of Li is found to be electron beam orientation sensitive and this property is used to assign the origin of the various Li 1s ELNES features. Information about core-hole screening by the valence electrons and charge transfer in the LIG systems is obtained from the C 1s ELNES and valence charge density difference calculations, respectively.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Oxford Editor
Language Wos 000268429000025 Publication Date 2009-05-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0008-6223; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 6.337 Times cited 12 Open Access
Notes Fwo G.0425.05; Esteem 026019 Approved Most recent IF: 6.337; 2009 IF: 4.504
Call Number UA @ lucian @ c:irua:77973 Serial 638
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Author Kruse, P.; Schowalter, M.; Lamoen, D.; Rosenauer, A.; Gerthsen, D.
Title Determination of the mean inner potential in III-V semiconductors, Si and Ge by density functional theory and electron holography Type A1 Journal article
Year 2006 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 106 Issue 2 Pages 105-113
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication Editor
Language Wos 000234535900005 Publication Date 2005-07-29
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 50 Open Access
Notes Approved Most recent IF: 2.843; 2006 IF: 1.706
Call Number UA @ lucian @ c:irua:56143 Serial 678
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Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Effect of temperature on the 002 electron structure factor and its consequence for the quantification of ternary and quaternary III-V crystals Type A1 Journal article
Year 2008 Publication Springer proceedings in physics Abbreviated Journal
Volume 120 Issue Pages 189-194
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication Berlin Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0930-8989 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:73965 Serial 839
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Author Rosenauer, A.; Schowalter, M.; Titantah, J.T.; Lamoen, D.
Title An emission-potential multislice approximation to simulate thermal diffuse scattering in high-resolution transmission electron microscopy Type A1 Journal article
Year 2008 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 108 Issue 12 Pages 1504-1513
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Thermal diffuse scattered electrons significantly contribute to high-resolution transmission electron microscopy images. Their intensity adds to the background and is peaked at positions of atomic columns. In this paper we suggest an approximation to simulate intensity of thermal diffuse scattered electrons in plane-wave illumination transmission electron microscopy using an emission-potential multislice algorithm which is computationally less intensive than the frozen lattice approximation or the mutual intensity approach. Intensity patterns are computed for Au and InSb for different crystal orientations. These results are compared with intensities from the frozen lattice approximation based on uncorrelated vibration of atoms as well as with the frozen phonon approximation for Au. The frozen phonon method uses a detailed phonon model based on force constants we computed by a density functional theory approach. The comparison shows that our suggested emission-potential method is in close agreement with both the frozen lattice and the frozen phonon approximations.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Amsterdam Editor
Language Wos 000260808300002 Publication Date 2008-04-21
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 25 Open Access
Notes Approved Most recent IF: 2.843; 2008 IF: 2.629
Call Number UA @ lucian @ c:irua:72919 Serial 1033
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Author Rosenauer, A.; Schowalter, M.; Glas, F.; Lamoen, D.
Title First-principles calculations of 002 structure factors for electron scattering in strained InxGa1-xAs Type A1 Journal article
Year 2005 Publication Physical Review B Abbreviated Journal Phys Rev B
Volume 72 Issue 8 Pages 1-10
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract This work provides values of electron scattering 002 structure factors for InxGa1-xAs as a function of the In concentration x=0 to 1. These results allow accurate compositional analysis of pseudomorphically grown InxGa1-xAs/GaAs layers by transmission electron microscopy methods relying on the chemical sensitivity of the (002) beam. The calculations go beyond the limits of the isolated atom approximation, because they take into account charge redistribution effects between atomic sites in the crystal, strain, and static atomic displacements. The computations were performed by the full potential linearized augmented plane-wave method using a generalized gradient approximation for the exchange and correlation part of the potential. The calculations of strained InxGa1-xAs correspond to the strain state in specimens with large, small, and intermediate thickness in the electron beam direction. Additionally, the effect of static atomic displacements is taken into account. All results are listed in a parameterized form. The calculated 002 structure factor vanishes at an In concentration of 16.4%. This value is in a good agreement with previously reported experimental measurements. Hence, our results are a significant improvement with respect to the isolated atom approximation which is conventionally applied in transmission electron microscopy simulations, and which predicts a value of 22.5%.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Lancaster, Pa Editor
Language Wos 000231564600106 Publication Date 2005-08-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 42 Open Access
Notes Approved Most recent IF: 3.836; 2005 IF: 3.185
Call Number UA @ lucian @ c:irua:54918 Serial 1201
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Author Rosenauer, A.; Schowalter, M.; Glas, F.; Lamoen, D.
Title First-principles calculations of 002 structure factors for electron scattering in strained InxGa1-xAs Type A1 Journal article
Year 2005 Publication Abbreviated Journal
Volume 107 Issue Pages 151-154
Keywords A1 Journal article; Electron Microscopy for Materials Science (EMAT);
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication Berlin Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0930-8989 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:72916 Serial 1202
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Author Verbeeck, J.; Sc hattschneider, P.; Rosenauer, A.
Title Image simulation of high resolution energy filtered TEM images Type A1 Journal article
Year 2009 Publication Ultramicroscopy Abbreviated Journal Ultramicroscopy
Volume 109 Issue 4 Pages 350-360
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract Inelastic image simulation software is presented, implementing the double channeling approximation which takes into account the combination of multiple elastic and single inelastic scattering in a crystal. The approach is described with a density matrix formalism. Two applications in high resolution energy filtered (EFTEM) transmission electron microscopy (TEM) images are presented: thickness-defocus maps for SrTiO3 and exit plane intensities for an (LaAlO3)3(SrTiO3)3 multilayer system. Both systems show a severe breakdown in direct interpretability which becomes worse for higher acceleration voltages, thicker samples and lower excitation edge energies. Since this effect already occurs in the exit plane intensity, it is a fundamental limit and image simulations in EFTEM are indispensable just as they are indispensable for elastic high resolution TEM images.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Amsterdam Editor
Language Wos 000265345400009 Publication Date 2009-01-17
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 36 Open Access
Notes Fwo; Esteem 026019 Approved Most recent IF: 2.843; 2009 IF: 2.067
Call Number UA @ lucian @ c:irua:77272UA @ admin @ c:irua:77272 Serial 1552
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Author Rossi, E.H.M.; Van Tendeloo, G.; Rosenauer, A.
Title Influence of strain, specimen orientation and background estimation on composition evaluation of InAs/GaAs by TEM Type A1 Journal article
Year 2007 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume 87 Issue 29 Pages 4461-4473
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication London Editor
Language Wos 000249890700003 Publication Date 2007-09-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-6435;1478-6443; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.505 Times cited 1 Open Access
Notes Approved Most recent IF: 1.505; 2007 IF: 1.486
Call Number UA @ lucian @ c:irua:66612 Serial 1638
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Author Rosenauer, A.; Gerthsen, D.; Van Aert, S.; van Dyck, D.; den Dekker, A.J.
Title Present state of the composition evaluation of ternary semiconductor nanostructures by lattice fringe analysis Type A1 Journal article
Year 2003 Publication Institute of physics conference series Abbreviated Journal
Volume Issue 180 Pages 19-22
Keywords A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab
Abstract Semiconductor heterostructures are used for the fabrication of optoelectronic devices. Performance of such devices is governed by their chemical morphology. The composition distribution of quantum wells and dots is influenced by kinetic growth processes which are not understood completely at present. To obtain more information about these effects, methods for composition determination with a spatial resolution at a near atomic scale are necessary. In this paper we focus on the present state of the composition evaluation by the lattice fringe analysis (CELFA) technique and explain the basic ideas, optimum imaging conditions, precision and accuracy.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Editor
Language Wos Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0-7503-0979-2 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ lucian @ c:irua:95118 Serial 2710
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Author Müller, K.; Schowalter, M.; Rosenauer, A.; Jansen, J.; Tsuda, K.; Titantah, J.T.; Lamoen, D.
Title Refinement of chemically sensitive structure factors using parallel and convergent beam electron nanodiffraction Type A1 Journal article
Year 2010 Publication Journal of physics : conference series Abbreviated Journal
Volume 209 Issue 1 Pages 012025-012025,4
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We introduce a new method to measure structure factors from parallel beam electron diffraction (PBED) patterns. Bloch wave refinement routines were developed which can minimise the difference between simulated and experimental Bragg intensities via variation of structure factors, Debye parameters, specimen thickness and -orientation. Due to plane wave illumination, the PBED refinement is highly efficient not only in computational respect, but also concerning the experimental effort since energy filtering is shown to have no significant effect on the refinement results. The PBED method was applied to simulated GaAs diffraction patterns to derive systematic errors and rules for the identification of plausible refinement results. The evaluation of experimental GaAs PBED patterns yields a 200 X-ray structure factor of -6.33±0.14. Additionally, we obtained -6.35±0.13 from two-dimensional convergent beam electron diffraction refinements. Both results confirm density functional theory calculations published by Rosenauer et al. and indicate the inaccuracy of isolated atom scattering data, which is crucial e.g. for the composition evaluation by lattice fringe analysis.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Bristol Editor
Language Wos Publication Date 2010-02-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 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:85761 Serial 2855
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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 (down) 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
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Author Piscopiello, E.; Rosenauer, A.; Passaseo, A.; Montoya Rossi, E.H.; Van Tendeloo, G.
Title Segregation in InxGa1-xAs/GaAs Stranski-Krastanow layers grown by metal-organic chemical vapour deposition Type A1 Journal article
Year 2005 Publication Philosophical magazine Abbreviated Journal Philos Mag
Volume 85 Issue 32 Pages 3857-3870
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication London Editor
Language Wos 000233171500007 Publication Date 2005-11-10
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1478-6435;1478-6443; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 1.505 Times cited 11 Open Access
Notes Approved Most recent IF: 1.505; 2005 IF: 1.470
Call Number UA @ lucian @ c:irua:59054 Serial 2961
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Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Size effects and strain state of Ga1-xInxAs/GaAs multiple quantum wells: Monte Carlo study Type A1 Journal article
Year 2008 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 78 Issue 16 Pages 165326,1-165326,7
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract The effect of the size of the GaAs barrier and the Ga1−xInxAs well on the structural properties of a Ga1−xInxAs/GaAs multiple quantum well structure is investigated using the Metropolis Monte Carlo approach based on a well-parametrized Tersoff potential. It is found that within the well the Ga-As and In-As bond lengths undergo contractions whose magnitude increases with increasing In content in sharp contrast with bond-length variations in the bulk Ga1−xInxAs systems. For fixed barrier size and In content, the contraction of the bonds is also found to increase with increasing size of the well. Using the local atomic structure of the heterostructures, a more local analysis of the strain state of the systems is given and comparison with the prediction of macroscopic continuum elasticity theory shows deviations from the latter.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Lancaster, Pa Editor
Language Wos 000260574500084 Publication Date 2008-10-28
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 5 Open Access
Notes Approved Most recent IF: 3.836; 2008 IF: 3.322
Call Number UA @ lucian @ c:irua:72920 Serial 3036
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Author Schowalter, M.; Rosenauer, A.; Titantah, J.T.; Lamoen, D.
Title Temperature-dependent Debye-Waller factors for semiconductors with the wurtzite-type structure Type A1 Journal article
Year 2009 Publication Acta crystallographica: section A: foundations of crystallography Abbreviated Journal Acta Crystallogr A
Volume 65 Issue Pages 227-231
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract We computed Debye-Waller factors in the temperature range from 0.1 to 1000 K for AlN, GaN, InN, ZnO and CdO with the wurtzite-type structure. The Debye-Waller factors were derived from phonon densities of states obtained from Hellmann-Feynman forces computed within the density-functional-theory formalism. The temperature dependences of the Debye-Waller factors were fitted and fit parameters are given.
Address
Corporate Author Thesis
Publisher (down) Place of Publication Copenhagen Editor
Language Wos 000264927100006 Publication Date 2009-03-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0108-7673; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 5.725 Times cited 23 Open Access
Notes Fwo G.0425.05; Esteem 026019 Approved Most recent IF: 5.725; 2009 IF: 49.926
Call Number UA @ lucian @ c:irua:74565 Serial 3497
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Author Titantah, J.T.; Lamoen, D.; Schowalter, M.; Rosenauer, A.
Title Temperature effect on the 002 structure factor of ternary Ga1-xInxAs crystals Type A1 Journal article
Year 2007 Publication Physical review : B : condensed matter and materials physics Abbreviated Journal Phys Rev B
Volume 76 Issue 7 Pages 073303,1-4
Keywords A1 Journal article; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication Lancaster, Pa Editor
Language Wos 000249155300011 Publication Date 2007-08-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1098-0121;1550-235X; ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor 3.836 Times cited 3 Open Access
Notes Approved Most recent IF: 3.836; 2007 IF: 3.172
Call Number UA @ lucian @ c:irua:66116 Serial 3499
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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 (down) 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
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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 (down) 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
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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 (down) 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
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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.
Address
Corporate Author Thesis
Publisher (down) 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
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Author Guzzinati, G.; Ghielens, W.; Mahr, C.; Béché, A.; Rosenauer, A.; Calders, T.; Verbeeck, J.
Title Electron Bessel beam diffraction patterns, line scan of Si/SiGe multilayer Type Dataset
Year 2019 Publication Abbreviated Journal
Volume Issue Pages
Keywords Dataset; ADReM Data Lab (ADReM); Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher (down) Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:169114 Serial 6865
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