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An EBSD pattern consists of a number of Kikuchi bands. Each band comprises a pair of parallel Kikuchi lines. The incident electron beam is directed to the point of interest (POI) on the sample surface and thus, the elastic scattering of the electron beam induces the electrons to diverge from a point just below the sample surface and to impinge on crystal planes in all directions. The atoms in materials scatter inelastically a fraction of the electrons with a small energy loss to form a divergent source of electrons close to the surface of the sample. Some of these electrons are incident on crystalline planes at angles which satisfy the Bragg’s law. These electrons are reflected to form a set of paired cones producing the characteristic Kikuchi bands. Figure 2342a (a) and (b) shows the formation of Kikuchi lines and electron backscatter diffraction pattern in different ways.
Figure 2342a (a) and (b). The formation of Kikuchi lines and electron backscatter diffraction pattern in different ways.
Figure 2342b shows the formation of a Ge (germanium) EBSD pattern projected onto a sphere centered at the PC (pattern center). These kinematically simulated Kikuchi bands (the gray lines enclosing the bright bands) had been widened by a factor of 2 from their Bragg angles to ensure that the EBSD bands are fully enclosed.
Figure 2342b. The formation of a Ge EBSD pattern projected onto a sphere centered at the PC (pattern center). [1]
[1] Jay Basinger, David Fullwood, Josh Kacher, and Brent Adams, Pattern Center Determination in Electron Backscatter Diffraction Microscopy, Microsc. Microanal. 17, 330–340, 2011.
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