Applications of aberration corrected scanning transmission electron microscopy and electron energy loss spectroscopy to thin oxide films and interfaces

Aberration correction in the scanning transmission electron microscope allows spatial resolutions of the order of one Ångström to be routinely achieved. When combined with electron energy loss spectroscopy, it is possible to simultaneously map the structure, the chemistry and even the electronic properties of materials in one single experiment. Here we will apply these techniques to the characterization of thin films and interfaces based on complex oxides with the perovskite structure. The relatively large lattice parameter of these materials combined with the fact that most of them have absorption edges within the reach of the spectrometer optics makes these materials ideal for these experiments. We will show how it is possible to map the chemistry of interfaces atomic plane by atomic plane, including light elements such as O. Applications to cobaltite and titanate thin films will be described.