Lawrence Berkeley National Laboratory
Reaching sub-Angstrom resolution with a mid-voltage TEM
- Author(s): O'Keefe, Michael A.
- Hetherington, Crispin J.D.
- Nelson, E. Chris
- et al.
Phase-contrast imaging in the high-resolution electron micrscope produces images with peaks at atom positions by extracting the spatial distribution of the relative phase from the electron wave. Usually, the electron wave is imaged by direct interference of diffracted beams at optimum focus. Instead, the One-Angstrom Microscope uses focal-series reconstruction software to derive the relative electron phase from a series of images taken over a range of focus, with peaks that correspond to the atom positions at a resolution that extends to the microscope information limit. Tests using a silicon specimen tilted into  orientation show that the O Angstrom M has achieved a world-record resolution of 0.78 Angstrom.