| AVS 66th International Symposium & Exhibition | |
| 2D Materials | Tuesday Sessions |
| Session 2D+AS+MI+NS-TuM |
| Session: | 2D Materials Characterization including Microscopy and Spectroscopy |
| Presenter: | Alessandra Bellissimo, ETH Zürich, Switzerland |
| Authors: | A. Bellissimo, ETH Zürich, Switzerland G.M. Pierantozzi, CNR - Istituto Officine Materiali, Italy A. Ruocco, Università degli Studi Roma Tre, Italy G. Stefani, Università degli Studi Roma Tre, Italy O. Ridzel, Technische Universität Wien, Austria V. Astašauskas, Technische Universität Wien, Austria W.S.M. Werner, Technische Universität Wien, Austria M. Taborelli, CERN, Switzerland G. Bertolini, ETH Zürich, Switzerland U. Ramsperger, ETH Zürich, Switzerland O. Gürlü, ETH Zürich, Switzerland, Turkey D. Pescia, ETH Zürich, Switzerland |
| Correspondent: | Click to Email |
The mechanisms responsible for electron-induced Secondary Electron Emission (SEE) generation of these ubiquitous Secondary Electrons (SEs) in a solid surface is not yet fully understood. In particular, the question how many “true secondary” electrons are generated and emitted from the target per incident primary electron awaits resolution and is of great fundamental as well as technological importance. The present work reports on a study of these and related questions by means of a variety of spectroscopic tools of increasing finesse. The interaction of Low-Energy Electrons with surfaces exhibiting different long-range order, was investigated by combining measurements of the Total Electron Yield in absolute units, single-electron as well as (e,2e)-coincidence spectroscopy. This investigation has led to the disentanglement of the elementary processes that need to be considered and comprehended for the understanding of the SE-generation probability, fully taking into account both energy and momentum conservation in the collision and the band structure of the solid. Single ionising scattering events, assisted by collective excitations, i.e. plasmons, constitute one of the fundamental ingredients leading to SEE. In the Low-Energy-regime the electron yield of a material is constituted by the interplay of reflectivity and SEE, both strongly dictated by the target band structure. The gathered information is further used in an attempt to interpret the signal generation mechanisms relevant in Scanning Field-Emission Microscopy (SFEM) [1].
Reference:
[1] A. Bellissimo, PhD Thesis, "Multiparameter Analysis of Genesis and Evolution of Secondary Electrons produced in the Low Energy Regime", URL:
https://www.researchgate.net/publication/332684398_Multiparameter_Analysis_of_Genesis_and_Evolution_of_Secondary_Electrons_produced_in_the_Low_Energy_regime