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Complete understanding of atomic resolution high-angle annular dark-field (Z-contrast) images requires quantitative agreement between simulations and experiments. We show that intensity variations can be placed on an absolute scale by normalizing the measured image intensities to the incident beam. We construct fractional intensity images of a SrTiO3 single crystal for regions of different thickness up to 120 nm. Experimental images are compared directly with image simulations. Provided that spatial incoherence is taken into account in the simulations, almost perfect agreement is found between simulation and experiment.

We show that an annular detector placed within the bright field cone in scanning transmission electron microscopy allows direct imaging of light elements in crystals. In contrast to common high angle annular dark field imaging, both light and heavy atom columns are visible simultaneously. In contrast to common bright field imaging, the images are directly and robustly interpretable over a large range of thicknesses. We demonstrate this through systematic simulations and present a simple physical model to obtain some insight into the scattering dynamics.

The simultaneous measurement of structural and chemical information at the atomic scale provides fundamental insights into the connection between form and function in materials science and nanotechnology. We demonstrate structural and chemical mapping in Bi(0.5) Sr(0.5) MnO3 using an aberration-corrected scanning transmission electron microscope. Two-dimensional mapping is made possible by an adapted method for fast acquisition of electron energy-loss spectra. The experimental data are supported by simulations, which help to explain the less intuitive features.

Determining both cation and oxygen sublattices of grain boundaries is essential to understand the properties of oxides. Here, with scanning transmission electron microscopy, electron energy-loss spectroscopy, and first-principles calculations, both the Ce and oxygen sublattices of a (210)Σ5 CeO(2) grain boundary were determined. Oxygen vacancies are shown to play a crucial role in the stable grain boundary structure. This finding paves the way for a comprehensive understanding of grain boundaries through the atomic scale determination of atom and defect locations.

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The aberration-corrected scanning transmission electron microscope allows probes to be formed with less than 1-Å diameter, providing sufficient sensitivity to observe individual Hf atoms within the SiO 2 passivating layer of a HfO 2 / SiO 2 / Si alternative gate dielectric stack. Furthermore, the depth resolution is sufficient to localize the atom positions to half-nanometer precision in the third dimension. From a through-focal series of images, we demonstrate a three-dimensional reconstruction of the Hf atom sites, representing a three-dimensional map of potential breakdown sites within the gate dielectric.