CASINO: A new monte Carlo code in C language for electron beam interactions—part III: Stopping power at low energies

Abstract

This paper is a description of the stopping power routine utilized in the CASINO program that is based on the experimental measurement of the energy loss function (ELF). In addition, we present an ANSI C standard program that can be used to generate the data needed for the stopping power routine. Both optical and energy loss spectrum (ELS) measurements of the ELF can be used as input to compute the stopping power. For ELS, only the single scattering spectrum is needed. Hence, measurement of the stopping power for a given element or compound of interest can easily be performed and used in the CASINO program. The resulting effect of using these stopping powers in Monte Carlo simulations is generally to increase the backscattering coefficient. Except for carbon, the change of stopping power for pure elements so far compiled is relatively small. In some compounds (i.e., Al 2 O 3 and ZnSe), the discrepancy with the Joy and Luo (1989) expression is significant.

Modeling the secondary emission yield of salty ice dust grains

“…Thus, a continuous slowing-down equation based on the Bethe stopping power expression (Bethe, 1933) usually simulates the energy losses. However, in the low-energy range, this expression must be reevaluated since the number of inelastic events is decreasing (e.g., Hovington et al, 1997b).…”

The effect of fast secondary electrons on X‐ray microanalysis in the scanning electron microscope

“…Equation (25) has been shown to be accurate to energy as low as 100 eV by Joy et al (1996) where the classical Bethe equation fails at energy roughly equals to 6J i . When a diffusing electron is moving from one region of homogeneous composition to another region of different homogeneous composition, the computation of L i is performed using this equation (Hovington et al 1997b) : (29) where λ j T is the total mean free path of region i and L j is the distance traveled by the electron in region j. If the computed value of L i indicates than the electron is diffusing in a new region, Eq.…”

Monte Carlo modeling of cathodoluminescence generation using electron energy loss curves

“…A number of continuous slowing down and elastic scattering models is implemented. Simulations for this study were performed using tabulated elastic Mott cross sections calculated using relativis-tic Hartree-Fock-Slater atomic potentials (Drouin et al 1997) and the modified Bethe stopping power expression (Hovington et al 1997b). Modifications were made to the CASI-NO source code in order to model depth and lateral total energy loss profiles as described below.…”