Computer simulation of ion-solid interaction processes

Application of grazing angles of incidence of ions on the solid surface opens
new perspectives in investigation of composition, structure and topography of
real surfaces and their modification and polishing by ion beams.
In present work the peculiarities of ion-solid interaction processes have been
investigated by computer simulation. The present code is based on the binary
collision approximation by using Newton equation for construction of
trajectories of colliding particles. For description of interaction between
particles the universal Biersack-Littmark-Ziegler potential is used. Both
elastic and inelastic energy losses are taken into account. The inelastic
energy losses are considered as local. The scattering integral is solved
numerically using quadratic Gauss method. Thermal vibrations of lattice atoms
are considered as randomize on Gauss distribution. Computer code described by
Pascal allows observing the dynamics of ion-solid interaction processes.
Ion scattering, sputtering and implantation into the Cu(001) and GaAs(001)
surfaces under conditions of low-energy ion bombardment at grazing incidence
have been investigated. The depth distributions of 5 keV Ar ions implanted
into Cu(001) surface and 1 keV Be and Se ions implanted into GaAs(001) have
been calculated.
The obtained results allow to select the optimum conditions for layer-by-layer
sputtering and obtaining implanted depth distributions with demanded shape in
narrow near-surface area (5-10 atom layers) of crystals. Application of
present code for investigation of diagnostics and modification of solid state
surface is discussed.