Expanding the horizons of EELS through advanced integration of the Iliad EELS filter

Electron energy loss spectroscopy is an established technique broadly applied to various materials to investigate their structure, chemistry and electronic properties at the local scale. For EELS investigations the setting of both the TEM and the EELS filter optics plays a crucial role for the reliable high quality of the produced data. The optics of the whole EELS setup is rather challenging: a broad range of electron energies must be simultaneously transferred through the microscope and through the spectrometer, from specimen to detector, without introducing chromatic blur or chromatic distortions. Together with it, when optimizing the experimental conditions aiming for the specific results one is constantly modifying the setting of both the microscope, such as the camera length, and the spectrometer, for example, the dispersions – introducing the extra challenges to maintain the accurate transfer. To ensure the superior performance and the quality of the EELS data, we closely integrated the optics of the TEM and the EELS filter. Together with this, the close integration of the EELS filer and the TEM column expands the possibilities for the multimodal use of the advanced TEM techniques, such as for example simultaneous EELS and EDX [1]. A new Zebra EELS detector, dedicated for the EELS data collection was developed. In this contribution we will talk on the advances of close integration of the TEM column and the EELS filter, Always-in-Focus technology, and highlight it with several practical examples covering the broad range of the applications of the new Iliad STEM platform. The application of both the MultiEELS™ mode [2] and XEELS™ mode [3] will be shown.