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Use of Monte Carlo Modeling to Aid Interpretation and Quantification of the Low Energy-Loss Electron Yield at Low Primary Energies

Published online by Cambridge University Press:  16 September 2008

Christopher Bonet ,
Andrew Pratt ,
Mohamed M. El-Gomati ,
Jim A.D. Matthew  and
Steven P. Tear
Christopher Bonet
Affiliation:
Department of Physics, University of York, Heslington, York YO10 5DD, UK
Andrew Pratt
Affiliation:
Department of Physics, University of York, Heslington, York YO10 5DD, UK
Mohamed M. El-Gomati
Affiliation:
Department of Electronics, University of York, Heslington, York YO10 5DD, UK
Jim A.D. Matthew
Affiliation:
Department of Physics, University of York, Heslington, York YO10 5DD, UK
Steven P. Tear*
Affiliation:
Department of Physics, University of York, Heslington, York YO10 5DD, UK
*
Corresponding author. E-mail: [email protected]
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Abstract

Experimental low-loss electron (LLE) yields were measured as a function of loss energy for a range of elemental standards using a high-vacuum scanning electron microscope operating at 5 keV primary beam energy with losses from 0 to 1 keV. The resulting LLE yield curves were compared with Monte Carlo simulations of the LLE yield in the particular beam/sample/detector geometry employed in the experiment to investigate the possibility of modeling the LLE yield for a series of elements. Monte Carlo simulations were performed using both the Joy and Luo [Joy, D.C. & Luo, S., Scanning11(4), 176–180 (1989)] expression for the electron stopping power and recent tabulated values of Tanuma et al. [Tanuma, S. et al., Surf Interf Anal37(11), 978–988 (2005)] to assess the influence of the more recent stopping power data on the simulation results. Further simulations have been conducted to explore the influence of sample/detector geometry on the LLE signal in the case of layered samples consisting of a thin C overlayer on an elemental substrate. Experimental LLE data were collected from a range of elemental samples coated with a thin C overlayer, and comparisons with Monte Carlo simulations were used to establish the overlayer thickness.

Keywords

electron microscopelow-loss electronbackscattered electronMonte CarlomodelingBSEscanning electron microscopeSEM
Type
Materials Applications
Information
Microscopy and Microanalysis , Volume 14 , Issue 5 , October 2008 , pp. 439 - 450
Copyright
Copyright © Microscopy Society of America 2008

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