Electron channelling contrast imaging of dislocations in a conventional SEM

Abstract

Dislocations in shock loaded tantalum single crystals were imaged using both transmission electron microscope (TEM) and electron channelling contrast image (ECCI) in a scanning electron microscope with a conventional backscattered electron detector. The results were compared with backscattered electron intensity profiles across dislocations calculated via the dynamic theory of electron diffraction. A one-to-one correspondence between ECCI and TEM is established. High voltage and low index reflections should be used to obtain the highest dislocation contrast and greatest imaging depth.

Keywords:

• Electron channelling
• electron microscopy
• dislocations
• tantalum
• computer simulation
• crystal defects
• defect analysis

Acknowledgement

We would like to thank Colin Humphreys and Mark Twigg for help concerning the diffraction calculations, Mike Mills for his interest and for a very useful conversation in Oxford and Gareth Douglas for help with the programming. We would also like to acknowledge some very helpful comments by an anonymous referee.

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