MICROSCOPY Vol.47▶No.4 2012
â– Reviews

Study of Annular Bright-Field STEM Imaging Based on Reciprocity

Eiji Abe and Ryo Ishikawa

Department of Materials Science & Engineering, University of Tokyo

Abstract: Recent developments of aberration-correction electron optics have successfully generated coherent electron beam with large convergent angles, which are now capable for annular-bright-filed (ABF) imaging in a scanning transmission electron microscope (STEM) and enable to detect extremely light atoms such as lithium and hydrogen. In this short article, based on reciprocity we attempt to interpret the origin of high-sensitivity of ABF imaging in relation with a hollow-cone illumination transmission electron microscopy. We also demonstrate that the hydrogen atom columns in a hydride crystal can be distinctly imaged as dark-dot, as anticipated from phase-contrast of a weak-phase object.

Key words: Atomic-resolution STEM, Aberration-corrected electron microscope, Annular-bright-filed method, Imaging light atoms