Image formation mechanisms of spherical aberration corrected BF STEM imaging methods

Abstract In this study, we explore the formation mechanisms of different spherical-aberration ( C s )-corrected bright-field (BF) scanning transmission electron microscope (STEM) imaging methods. The C s -corrected BF STEM imaging modes are characterised in detail using simulated images and experimental BF STEM images obtained with several types of detectors. The Co 3 O 4 specimen results show that the occupancy, the atomic spacing, and the atomic number of the atoms constituting the atomic columns control image formation in BF STEM imaging, which is used to detect light atomic columns. The middle-angle BF STEM image is crucial in image formation by BF STEM imaging.