Secondary electron energy loss coincidence (e,2e) spectroscopy on Ag and Si surfaces

6th Vacuum and Surface Sciences Conference of Asia and Australia

Khalid, Rahila^1 ; Pujol, Francesc Salvat^1 ; Werner, Wolfgang S. M.^1

Institute of Applied Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10/134, A-1040 Vienna, Austria^1

关键词: Backscattered electrons;    Emission of electron;    Linear-response theory;    Polycrystalline silver;    Qualitative information;    Secondary electron emissions;    Secondary electrons;    Surface excitations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/439/1/012003/pdf
DOI  :  10.1088/1742-6596/439/1/012003

来源: IOP

【 摘 要 】

Qualitative information on the mechanism of secondary electron emission with respect to loss processes has been gathered by measuring the coincidences between secondary electrons and inelastically backscattered electrons on a polycrystalline silver (Ag) and an amorphised silicon (Si) sample using a specially designed (e,2e) coincidence spectrometer. Primary electrons impinge on the sample with an energy of 100 eV. Correlated emission of electron pairs was observed with a hemispherical mirror analyzer (backscattered electrons with losses up to 50 eV) and a time of flight analyzer (secondary electrons with energies up to 50eV). A comparison of these experimental data with a Monte Carlo (MC) simulation model is made. It is found that surface excitations play an important role in secondary electron emission mechanism. For Ag, low energy loss distributions were compared with calculations using linear response theory and agreed satisfactorily even though the expected limit of validity of this type of theories is for energies ≥100 eV.