Diffraction contrast analysis of dislocations in 2D materials using true dark-field and 4D-STEM in SEM

Abstract

Diffraction techniques are ubiquitous in electron microscopy, especially in Transmission Electron Microscopy (TEM). TEM enables the use of an objective aperture placed in the diffraction plane to increase contrast in bright-field or dark-field mode. On the other hand, Scanning Electron Microscopy (SEM) also offers several diffraction techniques, such as EBSD and TKD. However, the exploration of on-axis transmission diffraction is still in its infancy. In recent years there have been several developments in this direction [1-3] to take advantage of the unique features of SEM, such as low acceleration voltages, large chamber size, and strong topographic contrast. However, further developments to also include an aperture system for dedicated diffraction contrast imaging have not been realized so far.

Parallel Acquisition of Real and Reciprocal Space Data in Transmission SEM

“…The heating stage utilizes DENSsolutions Wildfire Nano-Chips, which enables precise and fast heating and cooling of the specimen. The parallel access to real and reciprocal space during annealing experiments can help to unravel the complex interplay of phenomena during thin film processes, like, e.g., grain coarsening, dewetting and texture evolution during solid-state dewetting of metal films [6,7].…”