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Li K, Tang R, Zhu C, Chen T. Critical Review on Crystal Orientation Engineering of Antimony Chalcogenide Thin Film for Solar Cell Applications. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2304963. [PMID: 37939308 PMCID: PMC10787070 DOI: 10.1002/advs.202304963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 09/16/2023] [Indexed: 11/10/2023]
Abstract
The emerging antimony chalcogenide (Sb2 (Sx Se1-x )3 , 0 ≤ x ≤ 1) semiconductors are featured as quasi-1D structures comprising (Sb4 S(e)6 )n ribbons, this structural characteristic generates facet-dependent properties such as directional charge transfer and trap states. In terms of carrier transport, proper control over the crystal nucleation and growth conditions can promote preferentially oriented growth of favorable crystal planes, thus enabling efficient electron transport along (Sb4 S(e)6 )n ribbons. Furthermore, an in-depth understanding of the origin and impact of the crystal orientation of Sb2 (Sx Se1-x )3 films on the performance of corresponding photovoltaic devices is expected to lead to a breakthrough in power conversion efficiency. In fact, there are many studies on the orientation control of Sb2 (Sx Se1-x )3 colloidal nanomaterials. However, the synthesis of Sb2 (Sx Se1-x )3 thin films with controlled facets has recently been a focus in optoelectronic device applications. This work summarizes methodologies that are applied in the fabrication of preferentially oriented Sb2 (Sx Se1-x )3 films, including treatment strategies developed for crystal orientation engineering in each process. The mechanisms in the orientation control are thoroughly analyzed. An outlook on perspectives for the future development of Sb2 (Sx Se1-x )3 solar cells based on recent research and issues on orientation control is finally provided.
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Affiliation(s)
- Ke Li
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
- Institute of Energy, Hefei Comprehensive National Science Center, Hefei, 230041, P. R. China
| | - Rongfeng Tang
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
- Institute of Energy, Hefei Comprehensive National Science Center, Hefei, 230041, P. R. China
| | - Changfei Zhu
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
- Institute of Energy, Hefei Comprehensive National Science Center, Hefei, 230041, P. R. China
| | - Tao Chen
- Hefei National Research Center for Physical Sciences at the Microscale, CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, School of Chemistry and Materials Science, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
- Institute of Energy, Hefei Comprehensive National Science Center, Hefei, 230041, P. R. China
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Cios G, Winkelmann A, Nolze G, Tokarski T, Rychłowski Ł, Dan L, Bała P. Mapping of lattice distortion in martensitic steel-Comparison of different evaluation methods of EBSD patterns. Ultramicroscopy 2023; 253:113824. [PMID: 37572392 DOI: 10.1016/j.ultramic.2023.113824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 07/11/2023] [Accepted: 07/28/2023] [Indexed: 08/14/2023]
Abstract
To visualize the varying tetragonal distortions in high carbon martensitic steels by EBSD, two different approaches have been applied on backscattered Kikuchi diffraction (BKD) patterns. A band-edge refinement technique called Refined Accuracy (RA) (Oxford Instruments) is compared with a technique called Pattern Matching (PM), which optimizes the fit to a simulated BKD signal. RA distinguishes between hypothetical phases of different fixed c/a, while PM determines a best fitting continuous c/a by projective transformation of a master pattern. Both techniques require stored BKD patterns. The sensitivity of the c/a-determination was tested by investigating the microstructure of a ferritic steel with an expected c/a=1. The influence of the Kikuchi pattern noise on c/a was compared for a single or 40 averaged frames per measuring point, and turned out to be not significant. The application of RA and PM on the martensitic microstructure delivered qualitatively similar maps of c/a. The comparison of RA and PM shows that RA is suitably fast and precise during mapping the martensite c/a ratio in analyses of high carbon martensite, especially for fast initial surveys. As RA leads quantitatively to higher noise in c/a, the PM analysis can be used for higher precision results.
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Affiliation(s)
- Grzegorz Cios
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland.
| | - Aimo Winkelmann
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland
| | - Gert Nolze
- Federal Institute for Materials, Research and Testing (BAM), Unter den Eichen 87, 12205 Berlin, Germany; TU Bergakademie Freiberg, Institute for Mineralogy, Brennhausgasse 14, 09596 Freiberg, Germany
| | - Tomasz Tokarski
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland
| | - Łukasz Rychłowski
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland
| | - Leonid Dan
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland
| | - Piotr Bała
- Academic Centre for Materials and Nanotechnology, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland; Faculty of Metals and Industrial Computer Science, AGH University of Krakow, al. A. Mickiewicza 30, 30-059 Kraków, Poland
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Winkelmann A, Nolze G, Cios G, Tokarski T, Bała P, Hourahine B, Trager-Cowan C. Kikuchi pattern simulations of backscattered and transmitted electrons. J Microsc 2021; 284:157-184. [PMID: 34275156 DOI: 10.1111/jmi.13051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/15/2021] [Indexed: 11/29/2022]
Abstract
We discuss a refined simulation approach which treats Kikuchi diffraction patterns in electron backscatter diffraction (EBSD) and transmission Kikuchi diffraction (TKD). The model considers the result of two combined mechanisms: (a) the dynamical diffraction of electrons emitted coherently from point sources in a crystal and (b) diffraction effects on incoherent diffuse intensity distributions. Using suitable parameter settings, the refined simulation model allows to reproduce various thickness- and energy-dependent features which are observed in experimental Kikuchi diffraction patterns. Excess-deficiency features are treated by the effect of gradients in the incoherent background intensity. Based on the analytical two-beam approximation to dynamical electron diffraction, a phenomenological model of excess-deficiency features is derived, which can be used for pattern matching applications. The model allows to approximate the effect of the incident beam geometry as a correction signal for template patterns which can be reprojected from pre-calculated reference data. As an application, we find that the accuracy of fitted projection centre coordinates in EBSD and TKD can be affected by changes in the order of 10 - 3 - 10 - 2 if excess-deficiency features are not considered in the theoretical model underlying a best-fit pattern matching approach. Correspondingly, the absolute accuracy of simulation-based EBSD strain determination can suffer from biases of a similar order of magnitude if excess-deficiency effects are neglected in the simulation model.
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Affiliation(s)
- Aimo Winkelmann
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Kraków, Poland.,Department of Physics, SUPA, University of Strathclyde, Glasgow, UK
| | - Gert Nolze
- Federal Institute for Materials, Research and Testing (BAM), Berlin, Germany.,TU Bergakademie Freiberg, Institute for Mineralogy, Freiberg, Germany
| | - Grzegorz Cios
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Kraków, Poland
| | - Tomasz Tokarski
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Kraków, Poland
| | - Piotr Bała
- Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, Kraków, Poland
| | - Ben Hourahine
- Department of Physics, SUPA, University of Strathclyde, Glasgow, UK
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4
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Oishi-Tomiyasu R, Tanaka T, Nakagawa J. Distribution rules of systematic absences and generalized de Wolff figures of merit applied to electron backscatter diffraction ab initio indexing. J Appl Crystallogr 2021. [DOI: 10.1107/s1600576721002120] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
A new method for electron backscatter diffraction ab initio indexing is reported that adopts several methods originally invented for powder indexing. Distribution rules of systematic absences and error-stable Bravais lattice determination are used to eliminate the negative influence of non-visible bands and erroneous information from visible bands. In addition, generalized versions of the de Wolff figures of merit are proposed as a new sorting criterion for the obtained unit-cell parameters, which can be used in both orientation determination and ab initio indexing from Kikuchi patterns. Computational results show that the new figures of merit work well, similar to the original de Wolff Mn
. The ambiguity of the indexing solutions is also pointed out, which happens in particular for low-symmetry cells and may generate multiple distinct solutions even if very accurate positions of band centre lines and the projection centre are given. It is supposed that this is the reason why indexing was successful in an orthorhombic case but not in a triclinic cell.
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Burkhardt U, Borrmann H, Moll P, Schmidt M, Grin Y, Winkelmann A. Absolute Structure from Scanning Electron Microscopy. Sci Rep 2020; 10:4065. [PMID: 32132558 PMCID: PMC7055257 DOI: 10.1038/s41598-020-59854-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/04/2020] [Indexed: 11/18/2022] Open
Abstract
The absence of centrosymmetry in chiral and polar crystal structures is the reason for many technical relevant physical properties like optical birefringence or ferroelectricity. Other chirality related properties that are actually intensively investigated are unconventional superconductivity or unusual magnetic ordering like skyrmions in materials with B20 structure. Despite the often close crystal structure - property relation, its detection is often challenging due to superposition of domains with different absolute structure e.g. chirality. Our investigations of high quality CoSi crystals with B20 structure by both complementary methods X- ray (volume sensitive) and electron backscatter diffraction (EBSD) (surface sensitive) results the consistent assignment of the chirality and reveal fundamental differences in their sensitivity to chirality. The analysis of the surface of a CoSi crystal with domains of different chirality show the high spatial resolution of this method which opens the possibility to analyze the chirality in microstructures of technical relevant materials like thin films and catalysts.
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Affiliation(s)
- Ulrich Burkhardt
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany.
| | - Horst Borrmann
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - Philip Moll
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany.,École polytechnique fédéral de Lausanne, CH-1015, Lausanne, Switzerland
| | - Marcus Schmidt
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - Yuri Grin
- Max-Planck-Institut für Chemische Physik fester Stoffe, Dresden, Germany
| | - Aimo Winkelmann
- Laser Zentrum Hannover e.V, Hannover, Germany.,Academic Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059, Krakow, Poland
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Indexing electron backscatter diffraction patterns with a refined template matching approach. Ultramicroscopy 2019; 207:112845. [PMID: 31586829 DOI: 10.1016/j.ultramic.2019.112845] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 09/03/2019] [Accepted: 09/12/2019] [Indexed: 11/20/2022]
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Liu J, Lozano-Perez S, Wilkinson AJ, Grovenor CRM. On the depth resolution of transmission Kikuchi diffraction (TKD) analysis. Ultramicroscopy 2019; 205:5-12. [PMID: 31234103 DOI: 10.1016/j.ultramic.2019.06.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Revised: 05/26/2019] [Accepted: 06/09/2019] [Indexed: 10/26/2022]
Abstract
In this paper, we have analyzed the depth resolution that can be achieved by on-axis transmission Kikuchi diffraction (TKD) using a Zr-Nb alloy. The results indicate that the signals contributing to detectable Kikuchi bands originate from a depth of approximately the mean free path of thermal diffuse scattering (λTDS) from the bottom surface of a thin foil sample. This existing surface sensitivity can thus lead to the observation of different grain structures when opposite sides of a nano-crystalline foil are facing the incident electron beam. These results also provide a guideline for the ideal sample thickness for TKD analysis of ≤ 6λTDS, or 21 times the elastic scattering mean free path (λMFP) for samples of high crystal symmetry. For samples of lower symmetry, a smaller thickness ≤ 3λTDS, or ≤ 10λMFP is suggested.
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Affiliation(s)
- Junliang Liu
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom.
| | - Sergio Lozano-Perez
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
| | - Angus J Wilkinson
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
| | - Chris R M Grovenor
- Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom
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8
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Naresh-Kumar G, Bruckbauer J, Winkelmann A, Yu X, Hourahine B, Edwards PR, Wang T, Trager-Cowan C, Martin RW. Determining GaN Nanowire Polarity and its Influence on Light Emission in the Scanning Electron Microscope. NANO LETTERS 2019; 19:3863-3870. [PMID: 31035764 DOI: 10.1021/acs.nanolett.9b01054] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The crystal polarity of noncentrosymmetric wurtzite GaN nanowires is determined nondestructively in the scanning electron microscope using electron backscatter diffraction (EBSD). The impact of the nanowire polarity on light emission is then investigated using cathodoluminescence (CL) spectroscopy. EBSD can determine polarity of noncentrosymmetric crystals by interrogating differences in the intensity distribution of bands of the EBSD pattern associated with semipolar planes. Experimental EBSD patterns from an array of GaN nanowires are compared with theoretical patterns produced using dynamical electron simulations to reveal whether they are Ga- or N-polar or, as in several cases, of mixed polarity. CL spectroscopy demonstrates the effect of the polarity on light emission, with spectra obtained from nanowires of known polarity revealing a small but measurable shift (≈28 meV) in the GaN near band edge emission energy between those with Ga and N polarity. We attributed this energy shift to a difference in impurity incorporation in nanowires of different crystal polarity. This approach can be employed to nondestructively identify polarity in a wide range of noncentrosymmetric nanoscale material systems and provide direct comparison with their luminescence.
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Affiliation(s)
- G Naresh-Kumar
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
| | - J Bruckbauer
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
| | - A Winkelmann
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
- Laser Zentrum Hannover e.V. , 30419 Hannover , Germany
| | - X Yu
- Department of Electronic and Electrical Engineering , University of Sheffield , Sheffield S1 3JD , U.K
| | - B Hourahine
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
| | - P R Edwards
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
| | - T Wang
- Department of Electronic and Electrical Engineering , University of Sheffield , Sheffield S1 3JD , U.K
| | - C Trager-Cowan
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
| | - R W Martin
- Department of Physics, SUPA , University of Strathclyde , Glasgow G4 0NG , U.K
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Wilkinson AJ, Collins DM, Zayachuk Y, Korla R, Vilalta-Clemente A. Applications of multivariate statistical methods and simulation libraries to analysis of electron backscatter diffraction and transmission Kikuchi diffraction datasets. Ultramicroscopy 2019; 196:88-98. [DOI: 10.1016/j.ultramic.2018.09.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 09/16/2018] [Accepted: 09/20/2018] [Indexed: 11/28/2022]
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Discovery of novel solid solution Ca 3Si 3-x O 3+x N 4-2x : Eu 2+ phosphors: structural evolution and photoluminescence tuning. Sci Rep 2017; 7:18103. [PMID: 29273765 PMCID: PMC5741754 DOI: 10.1038/s41598-017-18319-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 12/08/2017] [Indexed: 11/23/2022] Open
Abstract
Discovery of novel phosphors is one of the main issues for improving the color rendering index (CRI) and correlated color temperature (CCT) of white light-emitting diodes (w-LEDs). This study mainly presents a systematic research on the synthesis, crystal structure variation and photoluminescence tuning of novel (oxy)nitride solid solution Ca3Si3−xO3+xN4−2x: Eu2+ phosphors. XRD refinements show that lattice distortion occurs when x value diverges the optimum one (x = 1). The lattice distortion causes a widening of emission spectrum and an increase of Stokes shift (ΔSS), which leads to a bigger thermal quenching. With decrease of x value, the emission spectrum shows an obvious red-shift from 505.2 to 540.8 nm, which is attributed to the crystal field splitting. The enhanced crystal field splitting also broadens the excitation spectrum, making it possible to serve as the phosphor for near ultraviolet (n-UV) LEDs. A 3-phosphor-conversion w-LED lamp was fabricated with the as-prepared phosphor, which exhibits high CRI (Ra = 85.29) and suitable CCT (4903.35 K). All these results indicate that the Ca3Si3−xO3+xN4−2x: Eu2+ phosphor can serve as the green phosphor for n-UV w-LEDs, with a tunable spectrum by controlling the crystal structure and morphology.
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Naresh-Kumar G, Vilalta-Clemente A, Jussila H, Winkelmann A, Nolze G, Vespucci S, Nagarajan S, Wilkinson AJ, Trager-Cowan C. Quantitative imaging of anti-phase domains by polarity sensitive orientation mapping using electron backscatter diffraction. Sci Rep 2017; 7:10916. [PMID: 28883500 PMCID: PMC5589861 DOI: 10.1038/s41598-017-11187-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 08/14/2017] [Indexed: 11/16/2022] Open
Abstract
Advanced structural characterisation techniques which are rapid to use, non-destructive and structurally definitive on the nanoscale are in demand, especially for a detailed understanding of extended-defects and their influence on the properties of materials. We have applied the electron backscatter diffraction (EBSD) technique in a scanning electron microscope to non-destructively characterise and quantify antiphase domains (APDs) in GaP thin films grown on different (001) Si substrates with different offcuts. We were able to image and quantify APDs by relating the asymmetrical intensity distributions observed in the EBSD patterns acquired experimentally and comparing the same with the dynamical electron diffraction simulations. Additionally mean angular error maps were also plotted using automated cross-correlation based approaches to image APDs. Samples grown on substrates with a 4° offcut from the [110] do not show any APDs, whereas samples grown on the exactly oriented substrates contain APDs. The procedures described in our work can be adopted for characterising a wide range of other material systems possessing non-centrosymmetric point groups.
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Affiliation(s)
- G Naresh-Kumar
- Department of Physics, SUPA, University of Strathclyde, Glasgow, G4 ONG, UK.
| | - A Vilalta-Clemente
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
| | - H Jussila
- Department of Electronics and Nanoengineering, Aalto University, FI-00076, Aalto, Finland
| | - A Winkelmann
- Bruker Nano GmbH, Am Studio 2D, 12489, Berlin, Germany
| | - G Nolze
- BAM, Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205, Berlin, Germany
| | - S Vespucci
- Department of Physics, SUPA, University of Strathclyde, Glasgow, G4 ONG, UK
| | - S Nagarajan
- Department of Electronics and Nanoengineering, Aalto University, FI-00076, Aalto, Finland
| | - A J Wilkinson
- Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH, UK
| | - C Trager-Cowan
- Department of Physics, SUPA, University of Strathclyde, Glasgow, G4 ONG, UK
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Nolze G, Hielscher R, Winkelmann A. Electron backscatter diffraction beyond the mainstream. CRYSTAL RESEARCH AND TECHNOLOGY 2016. [DOI: 10.1002/crat.201600252] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Gert Nolze
- Federal Institute for Materials Research and Testing (BAM); Berlin Germany
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Abstract
The inverse pole figure (IPF) coloring for a suitable evaluation of crystal orientation data is discussed. The major goal is a high correlation between encoding color and crystal orientation. Revised color distributions of the fundamental sectors are introduced which have the advantages of (1) being applicable for all point groups, (2) not causing color discontinuities within grains, (3) featuring carefully balanced regions for red, cyan, blue, magenta, green and yellow, and (4) an enlarged gray center in opposition to a tiny white center. A new set of IPF color keys is proposed which is the result of a thorough analysis of the colorization problem. The discussion considers several topics: (a) the majority of presently applied IPF color keys generate color discontinuities for specifically oriented grains; (b) if a unique correlation between crystal direction and color is requested, discontinuity-preventing keys are possible for all point groups, except for {\overline 4}, {\overline 3} and {\overline 1}; (c) for a specific symmetry group several IPF color keys are available, visualizing different features of a microstructure; and (d) for higher symmetries a simultaneous IPF mapping of two or three standard reference directions is insufficient for an unequivocal orientation assignment. All color keys are available in MTEX, a freely available MATLAB toolbox.
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