Zitieren Sie bitte immer diesen URN: urn:nbn:de:kobv:b43-422063
Diffraction effects and inelastic electron transport in angle-resolved microscopic imaging applications
- We analyse the signal formation process for scanning electron microscopic imaging applications on crystalline specimens. In accordance with previous investigations, we find nontrivial effects of incident beam diffraction on the backscattered electron distribution in energy and momentum. Specifically, incident beam diffraction causes angular changes of the backscattered electron distribution which we identify as the dominant mechanism underlying pseudocolour orientation imaging using multiple, angle-resolving detectors. Consequently, diffraction effects of the incident beam and their impact on the subsequent coherent and incoherent electron transport need to be taken into account for an in-depth theoretical modelling of the energy- and momentum distribution of electrons backscattered from crystalline sample regions. Our findings have implications for the level of theoretical detail that can be necessary for the interpretation of complex imaging modalities such as electron channellingWe analyse the signal formation process for scanning electron microscopic imaging applications on crystalline specimens. In accordance with previous investigations, we find nontrivial effects of incident beam diffraction on the backscattered electron distribution in energy and momentum. Specifically, incident beam diffraction causes angular changes of the backscattered electron distribution which we identify as the dominant mechanism underlying pseudocolour orientation imaging using multiple, angle-resolving detectors. Consequently, diffraction effects of the incident beam and their impact on the subsequent coherent and incoherent electron transport need to be taken into account for an in-depth theoretical modelling of the energy- and momentum distribution of electrons backscattered from crystalline sample regions. Our findings have implications for the level of theoretical detail that can be necessary for the interpretation of complex imaging modalities such as electron channelling contrast imaging (ECCI) of defects in crystals. If the solid angle of detection is limited to specific regions of the backscattered electron momentum distribution, the image contrast that is observed in ECCI and similar applications can be strongly affected by incident beam diffraction and topographic effects from the sample surface. As an application, we demonstrate characteristic changes in the resulting images if different properties of the backscattered electron distribution are used for the analysis of a GaN thin film sample containing dislocations.…
Autor*innen: | Aimo Winkelmann, Gert Nolze, S. Vespucci, N.-K. Gunsekar, C. Trager-Cowan, A. Vilalta-Clemente, A. J. Wilkinson, M. Voss |
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Dokumenttyp: | Zeitschriftenartikel |
Veröffentlichungsform: | Verlagsliteratur |
Sprache: | Englisch |
Titel des übergeordneten Werkes (Englisch): | Journal of Microscopy |
Jahr der Erstveröffentlichung: | 2017 |
Veröffentlichende Institution: | Bundesanstalt für Materialforschung und -prüfung (BAM) |
Verlag: | Wiley & Sons, Ltd. |
Jahrgang/Band: | 267 |
Ausgabe/Heft: | 3 |
Erste Seite: | 330 |
Letzte Seite: | 346 |
DDC-Klassifikation: | Naturwissenschaften und Mathematik / Chemie / Analytische Chemie |
Freie Schlagwörter: | Background processing; Backscattered electrons; Center of mass; Channeling-in; EBSD |
DOI: | 10.1111/jmi.12571 |
URN: | urn:nbn:de:kobv:b43-422063 |
ISSN: | 0022-2720 |
Verfügbarkeit des Dokuments: | Datei für die Öffentlichkeit verfügbar ("Open Access") |
Lizenz (Deutsch): | Creative Commons - Namensnennung |
Datum der Freischaltung: | 28.09.2017 |
Referierte Publikation: | Ja |
Datum der Eintragung als referierte Publikation: | 28.09.2017 |
Schriftenreihen ohne Nummerierung: | Wissenschaftliche Artikel der BAM |