Abstract
Aberration correction in scanning transmission electron microscopy represents a major breakthrough in
transmission electron microscopy, enabling the formation of sub-Angstrom probe sizes. Thus, electron microscopy
achieved single atom sensitivity. Here, we show how this technique with its unique spatial resolution in combination
with high-resolution electron energy-loss spectroscopy can be used to investigate atomic and electronic structures of
semiconductor interfaces with single atom sensitivity. We employ a Si/HfO2/SiO2/Si high-k dielectric interface to show
the presence of single Hf atoms in the SiO2 interlayer. Furthermore, we demonstrate how local dielectric properties and
local band structure information can be obtained by electron energy-loss spectroscopy.