Energy-Filtering Transmission Electron Microscopy

Publisher Summary In energy-filtering transmission electron microscopy (EFTEM), the zero-loss electrons or electrons passing an energy-loss window of the electron energy-loss spectroscopy (EELS) are used for image formation. This can be achieved by using the scanning mode in a dedicated scanning transmission electron microscope (STEM) or in a TEM with a spectrometer behind the camera chamber or by using an imaging filter lens in the column of a TEM. The conventional TEM and STEM modes can be combined in this way with the mode of electron spectroscopic imaging (ESI) and electron spectroscopic diffraction (ESD), and different modes can be used to record an EELS spectrum. An EFTEM can therefore make full use of elastic and inelastic electron-specimen interactions. This chapter provides an overview of the physical background and the possibilities of EFTEM. The relevant physics of elastic and inelastic scattering is also discussed followed by the instrumentation of EFTEM. The theoretical approaches for understanding the contrast and examples of application are presented for ESI and for ESD.