Automated crystal phase and orientation mapping of nanocrystals in a transmission electron microscope

Abstract

An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope (TEM) is described. It is based on the projected reciprocal lattice geometry that is extracted from electron diffraction spot patterns. The required hardware allows for a scanning‐precession movement of the primary electron beam on the crystalline sample and can be interfaced to any newer or older TEM. The software that goes with this hardware is flexible in its intake of raw data so that it can also create orientation and phase maps of nanocrystal from high resolution TEM (HRTEM) images. When the nanocrystals possess a structure with a small to medium sized unit cell, e.g. noble metals or minerals that possess the halite structural prototype, an objective‐lens aberration corrected microscope needs to be utilize for the recording of the HRTEM images that are to be processed by this software. Experimentally obtained crystal phase and orientation maps are shown for iron oxide and clausthalite ...