Timothy J. V. Yates

Nanoscale scanning transmission electron tomography.

Electron tomography enables the study of complex three‐dimensional objects with nanometre resolution. In materials science, scanning transmission electron microscopy provides images with minimal coherent diffraction effects and with high atomic number contrast that makes them ideal for electron tomographic reconstruction. In this study, we reviewed the topic of scanning transmission electron microscopy‐based tomography and illustrated the power of the technique with a number of examples with critical dimensions at the nanoscale.

Three-dimensional analysis of the dopant potential of a silicon p-n junction by holographic tomography

Off-axis electron holography and tomography have been combined to examine the 3-D electrostatic potential associated with a Si p-n junction. The device was prepared in a novel specimen geometry using focused ion beam milling and a series of holograms was acquired over a tilt range of −70° to +70°. Simultaneous iterative reconstruction was used to reconstruct the 3-D electrostatic potential in the specimen. The experimental results were compared to simulations of the potential variation. Quantitative results from the central, ‘bulk’ semiconducting regions and from the surface layers were extracted from the 3-D reconstruction.