Characterization of misfit dislocations in Si quantum well structures enabled by STEM based aberration correction

•STEM based Aberration Correction was critical to understanding the core structure of misfit dislocations in Si, confirming a Double Period reconstruction in 90° partial dislocations in Silicon.•Experience with aberration corrected probe forming systems has now been extended to EELS, producing better than 10meV resolution at 60keV for very low energy excitations such as phonons. The success of aberration correction techniques at the end of the 20th century came at a time of increasing need for atomic resolution imaging to better understand known structural defects that influence semiconductor device operation, and to advance the search for new structures and behavior that will form the basis for devices in the future. With this in mind, it is a pleasure to recognize the contributions of Ondrej Krivanek to the success of aberration correction techniques, and his extension of aberration techniques to EELS equipment that further promises to unite structural studies with characterization of behavior from meV to keV energies in the STEM.