Holographic Low Energy Electron Microscopy – HoloLEEM

The demand for advanced characterization tools applied to nanomaterials promotes the development of new techniques of microscopy. In that perspective we aim at developing a new prototype of instrument combining Holography principle and Low Energy Electron Microscopy.
Low Energy Electron Microscopy is a powerful in situ and real time imaging technique of nanomaterial surfaces. Processes such as chemical reactions, growth of nanostructures or thin films are commonly studied. To have access to the phase of the electron wave and to measure new physical properties we propose to implement an electrostatic biprism inside the microscope and to use the coherence properties of the electron beam to obtain a new imaging mode based on off-axis holography. This will lead to a unique microscope in the world and a breakthrough in the capacity of combining in situ measurements of magnetic, electric and structural properties on the same sample area with nanometer lateral resolution and sub-Ångstrom vertical resolutions. After test bed experiments to characterize the performances of the new setup, key nanomaterials properties are planned: 2D-electronic states at semiconducting/insulating surfaces, ferroelectricity, ferromagnetism and surface strain induced by a dislocation network formed via direct wafer bonding (Silicon).