DEVELOPMENTS IN EELS INSTRUMENTATION FOR SPECTROSCOPY AND IMAGING

Recent developments in instrumentation for electron energy loss spectroscopy (EELS) at Gatan R&D are reviewed. A 10-channel intrinsic Si detector with single-electron detection capability is being developed for fast energy-filtered imaging and elemental mapping in the STEM mode. A new type of an imaging filter suitable for attachment at the end of the electron-optical column of a transmission electron microscope has been designed and built. The design of the filter is described, and its electron-optical properties are compared with the properties of an optimized OMEGA-filter. Finally, an unconventional design of an ultra-high resolution electron spectrometer which does not use any retardation and yet should be able to attain an energy resolution of a few meV at primary energies around 200 keV is proposed.