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R. Khalid:
"Secondary electron emission studied by secondary electron electron energy loss coincidence spectrometer (SE2ELCS)";
Vortrag: Seminar Institut für Allgemeine Physik (IAP), TU Wien, Institut für Angewandte Physik; 12.03.2013.

To investigate the mechanisms responsible for the emission of secondary electrons, a reflection (e,2e) coincidence spectrometer named Secondary Electron Electron Energy Loss Coincidence Spectrometer (SE2ELCS) has been developed which allows one to uncover the relation between the features in the spectra which are due to energy losses and true secondary electron emission structures. Correlated electron pairs are measured with a hemispherical mirror analyzer (HMA) and a time of flight analyzer (TOF) by employing a continuous electron beam. An effort has been made to increase the coincidence count rate by increasing the effective solid angle of the TOF analyzer and optimizing the experimental parameters to get optimum energy resolution. Double differential coincidence spectra for free electron metals (Al, Si), noble metals (Ag, Au) and highly oriented pyrolytic graphite (HOPG) have been measured using this coincidence spectrometer. The interpretation of these data set will be presented using a semiclassical three step model based on linear response theory of semi-infinite solids.