Computer simulation of the angular dependence of backscattering of low energy noble gas ions from single crystal surfaces

Abstract

Abstract The intensity distributions of low energy noble gas ions backscattered from single crystal surfaces have been simulated by a computer programme. Comparisons of computer studies with experiments for He+ on W(110) and for Ne+ on Ni(110) are presented and a focusing effect outlined. In the calculations the binary collision approximation with the Moliere and the Born-Mayer potentials were used. Thermal vibrations of the target atoms as well as neutralization and inelastic energy losses of the ions are included. The target may have any crystal- and any topographic surface-structure. Displacement of lattice atoms by ion collision is based on an energy-threshold criterion. The directions and the intensities of the backscattered ion trajectories are plotted in the Lambert azimuthal polar and in the stereographic equatorial projections. Ions reflected in specified solid angle regions can be selected for the plot of the relative kinetic ion energy as a function of the scattering angle and for the plot of t...