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cECCI

cECCI: Electron Channeling Contrast Imaging under controlled diffraction conditions
Definition:A combination of electron backscatter diffraction (→EBSD) or electron channeling pattern (→ECP) and electron channeling contrast imaging (→ECCI) to obtain controlled imaging conditions for optimum defect contrast formation.
Explanation:When conventionally applying the ECCI technique for defect observation in a polycrystalline sample, it is not known which lattice plane leads to the observed defect contrast and whether the exact channeling conditions are excited; this can be corrected by measuring the crystal orientation with EBSD or ECP. When ECP is available (which is rarely the case of modern microscopes), then the channeling contrast can be directly selected by tilting the sample until a channeling (or Kikuchi) line runs through the centre of the pattern. Subsequently, the microscope is run in scanning mode and the desired channelling contrast is observed. When the orientation is measured by EBSD, a software is required to emulate the theoretically obtained ECP based on the measured orientation. This software also emulates the sample tilt required to obtain good channelling conditions. The software-determined tilt conditions are subsequently set to the microscope stage and channelling contrast is observed.

Generally, the ECP-based method is to be preferred over the EBSD-based one because the channelling conditions can be directly observed and set without errors, while in the EBSD-setup, many errors can occur (detector misorientation, stage misalignment etc.) and have to be corrected.
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Diagram:

Schematical view of the process of EBSD-based cECCI.
SFB-Link:cECCI is an important extension of ECCI for characterizing crystal defects in bulk materials.
References:S. Zaefferer, N.-N. Elhami: Theory and application of electron channelling contrast imaging under controlled diffraction conditions., Acta Materialia 75 (2014) 20–50