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The development of a method for the precise measurement of strain fields in semiconductor devices has become a critical requirement because the electrical performances of the devices are greatly influenced by the strain induced in their structures. We applied scanning moire fringe imaging to demonstrate the quantitative strain mapping of a Si/Si1−xGex interfacial layer. The strain field was measured at a nano-meter scale spatial resolution, with a detection precision of 0.1%. The maximum value of the strain was measured to be 1.1% ± 0.1%, which is consistent with the direct measurement by high-resolution scanning transmission electron microscopy image.

The defect structures around oxygen vacancies in perovskite-type oxides play very important roles in determining material properties through the change of the electronic state. Therefore, from the viewpoint of developing condensed matter physics and technological applications, it is crucial to obtain direct images of these structures. We report the simultaneous visualization of oxygen vacancies and the cation shifts around them in perovskite-type manganite by scanning transmission electron microscopy. The defective structure of the material makes it amenable to using Fourier analysis to obtain important structural information like the oxygen vacancy locations and the shift of nearby cation columns.

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.