EBSD pattern simulations for an interaction volume containing lattice defects

Abstract

A quantitative understanding of the effect of the spatial distribution and density of lattice defects on the electron backscatter diffraction patterns requires careful consideration of the electron-matter interaction volume and the traction free boundary condition on the deformation field for near-surface defects. In this work, we couple a depth-specific dynamical electron scattering simulation with an approximate crystal deformation model to generate a single diffraction pattern from an interaction volume containing lattice defects. Two case studies are considered, namely a single edge dislocation and a low angle grain boundary. Their displacement fields, derived from the three-dimensional Yoffe-Shaibani-Hazzeldine’s dislocation field model, are fed into the simulation and the resulting diffraction patterns are cross-validated using the HR-EBSD technique. In addition, diffraction contrast associated with defect deformation field is investigated with the virtual beam technique. Pattern diffuseness is quantitatively analyzed in the frequency domain as a function of dislocation density.