Sub-Angstrom high-resolution transmission electron microscopy at 300 keV.
Sub-Angstrom transmission electron microscopy has been achieved at the National Center for Electron Microscopy (NCEM) by a one-Angstrom microscope (OAM) project using software and enhanced hardware developed within a Brite-Euram project (Ultramicroscopy 64 (1996) 1). The NCEM OAM provides materials scientists with transmission electron microscopy at a resolution better than 1 A by using extensive image reconstruction to exploit the significantly higher information limit of an FEG-TEM over its Scherzer resolution limit. Reconstruction methods chosen used off-axis holograms and focal series of underfocused images. Measured values of coherence parameters predict an information limit of 0.78 A. Images from a [1 1 0] diamond test specimen show that sub-Angstrom resolution of 0.89 A has been achieved with the OAM using focal series reconstruction.
O'Keefe
M A
MA
Materials Science Division, National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA. maok@lbl.gov
Hetherington
C J
CJ
Wang
Y C
YC
Nelson
E C
EC
Turner
J H
JH
Kisielowski
C
C
Malm
J O
JO
Mueller
R
R
Ringnalda
J
J
Pan
M
M
Thust
A
A