Towards large scale orientation mapping using the eCHORD method.

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Electron Backscatter Diffraction (EBSD) is a common technique for orientation mapping.
• eCHORD (electron Channeling Orientation Mapping) offers an alternative using channeling contrast in Backscattered Electron (BSE) images.
• eCHORD's low sample tilt (10°) minimizes image deformation, making it suitable for large-scale mapping.

Purpose of the Study:

• To evaluate eCHORD as a large-scale orientation mapping technique.
• To address orientation errors in eCHORD caused by low-magnification beam deflection.
• To present a correction method and demonstrate its efficacy on a silicon single crystal.

Main Methods:

• Utilized channeling contrast in BSE images for orientation mapping.
• Implemented a correction method to compensate for scan deflection errors at low magnification.
• Acquired an orientation map on a silicon single crystal using the corrected eCHORD method.

Main Results:

• Identified orientation errors in eCHORD at low magnification due to beam deflection.
• Developed and applied a correction method for these orientation errors.
• Achieved an experimental misorientation of 0.12° across a 2.3 × 1.7 mm² field of view on a Si single crystal.

Conclusions:

• eCHORD is a viable alternative for large-scale orientation mapping, especially when minimizing image deformation is crucial.
• The proposed correction method effectively mitigates orientation errors caused by beam deflection.
• eCHORD, with the applied correction, demonstrates high accuracy for crystallographic orientation analysis over large areas.