It was recalled that it had recently been proposed that positron stopping profiles in elements and elemental multi-layers, calculated by Monte Carlo simulations of incident positron energies ranging from 1 to 10keV, could be scaled onto energy-independent curves by using the mean implantation depth. It was shown here that Monte Carlo stopping profiles in elemental multi-layer systems could be reproduced accurately, for incident energies which ranged from 1 to 25keV, by using a modification of this scaling model that took account of the back-scattering effect of interfaces. The mean-depth scaling approach led to a saving of some orders of magnitude in the computation time for multi-layer stopping profiles.

G.C.Aers, P.A.Marshall, T.C.Leung, R.D.Goldberg: Applied Surface Science, 1995, 85, 196-209