Dispersion-Compensation Electron-Energy-Loss Spectrometer

A dispersion-compensation electron-energy-loss spectrometer which consists of two 90° spherical sectors has been constructed and its characteristics have been tested. We have obtained the detector current of 160 pA with the full-width at half maximum of 25 meV for the primary electron energy of 19.5 eV in the direct mode, where electrons passing through the monochromator are directly detected by the analyzer without reflection from a sample. The obtained characteristics have been discussed, and suggestions for the design of an advanced spectrometer have been given.