Principles of High Resolution STEM Images (II)

Abstract

By improving coherence and brightness of electron beam, high-angle annular dark field scanning transmission electron microscopy (HAADF STEM) enables us to obtain incoherent images with comparable resolution of conventional high-resolution transmission electron microscopy. Recently, developments in correcting the aberration of the lens have pushed achievable spatial resolution into sub-ångstrom, thus providing a new level of analysis for local structures as well as electric states in areas such as nanotechnology. This review mainly shows how bight-field STEM images and Cs-corrected STEM images are understood through several key points.