Model based atomic resolution tomography

Electron tomography is a valuable three-dimensional characterization method, but the technique has so far been limited to a nanometer scale resolution, and therefore complementary two-dimensional structural analysis is generally performed using other techniques. In this paper, computer simulations of the latest transmission electron microscope technologies are performed on a CeO2 supercell to investigate the extension of electron tomography to the atomic scale resolution, from a tilt series of high resolution electron microscopy (HREM) images. We showed that high-voltage and aberration-corrected microscopes were both capable of retrieving adjacent oxygen and Ce atoms for a thickness up to 2.5 nm. In the case where only a few tilt angle projections are in zone-axis orientations, we introduced a hybrid tomography method, whereby a lattice-resolved tomogram obtained from a few zone-axis projections is combined with the external shape reconstruction of the crystal from binary projections. Finally, we discussed some experimental challenges related to the proposed HREM tomography technique. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3176900]