Electron Channelling Contrast Imaging in a Low Voltage Scanning Electron Microscope

Understanding of defects and their role in plastic deformation, as well as in device reliability, helps in the development a wide range of novel materials for the next generation of electronic and optoelectronic devices. Electron channelling contrast imaging (ECCI) performed in a scanning electron microscope (SEM) is a rapid and non-destructive structural characterisation technique for imaging defects such as dislocations in crystalline materials Changes in crystallographic orientation or local strain produce contrast in an image constructed by monitoring the intensity of backscattered electrons (BSEs) as an electron beam is scanned over a suitably orientated sample. Defects are imaged due to their resultant lattice plane distortions and local strain. Although ECCI provides the structural characterisation capability for various materials ranging from metals to ceramics, there are challenges in analysing low atomic weight, beam sensitive materials. One potential method is to minimise the interaction volume and thereby improve the spatial resolution of BSE images by employing low voltage SEMthe subject of our work.