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Dynamical Electron Backscatter Diffraction Patterns. Part I: Pattern Simulations

Published online by Cambridge University Press:  26 June 2013

Patrick G. Callahan
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
Marc De Graef*
Affiliation:
Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
*
*Corresponding author. E-mail: degraef@cmu.edu
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Abstract

A new approach for the simulation of dynamic electron backscatter diffraction (EBSD) patterns is introduced. The computational approach merges deterministic dynamic electron-scattering computations based on Bloch waves with a stochastic Monte Carlo (MC) simulation of the energy, depth, and directional distributions of the backscattered electrons (BSEs). An efficient numerical scheme is introduced, based on a modified Lambert projection, for the computation of the scintillator electron count as a function of the position and orientation of the EBSD detector; the approach allows for the rapid computation of an individual EBSD pattern by bi-linear interpolation of a master EBSD pattern. The master pattern stores the BSE yield as a function of the electron exit direction and exit energy and is used along with weight factors extracted from the MC simulation to obtain energy-weighted simulated EBSD patterns. Example simulations for nickel yield realistic patterns and energy-dependent trends in pattern blurring versus filter window energies are in agreement with experimental energy-filtered EBSD observations reported in the literature.

Type
Techniques and Software Development
Copyright
Copyright © Microscopy Society of America 2013 

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