Monte-Carlo calculations of positron implantation profiles in silver and gold

Abstract

To investigate the implantation profiles of positrons in silver and gold, the Monte-Carlo programs developed previously by Ozmutlu and Aydin (1997) to simulate the transport of positrons in metals was used. The simulation technique is mainly based on the screened Rutherford differential cross section with a spin-relativistic correction factor for the elastic scattering at high energies supplemented by total cross sections at low energies, Gryzinski's semi-empirical expression to simulate the energy loss due to inelastic scattering, and Liljequist's model to calculate the total inelastic scattering cross section. Backscattering probabilities and mean penetration depths were calculated from the implantation profiles of positions at energies between 1 and 50 keV, entering normally to semi-infinite silver and Sold targets. The calculated backscattering probabilities and mean penetration depths are compared with comparable Monte-Carlo data and experimental results for semi-infinite silver and gold targets. The agreement is quite satisfactory, at least, in parts.