BULK ATOMIC RELOCATION IN LOW-ENERGY COLLISION CASCADES IN SILICON - MOLECULAR-DYNAMICS VERSUS MONTE-CARLO SIMULATIONS

We investigate the atomic mixing produced in the bulk of a zero-temper ature silicon target by internally-starting low-energy (100 eV) self-r ecoils. Molecular Dynamics (MD) and Monte Carlo (MC) simulations are a pplied. The many-body Tersoff potential connected smoothly with the pa irlike Ziegler-Biersack potential is used in the MD simulation. The co llisional model of the MC code is based on the Ziegler-Biersack potent ial and includes a calculation of the mean free-flight path and the ra ndom impact parameter by using the energy-dependent total cross-sectio n for elastic collisions. For a quantitative description of the proces s of ion-induced atomic mixing we calculate the depth dependence of th e number of displaced atoms, and the first and second moments of the r elocation cross-section. We analyse the discrepancies between the two computer simulations, and suggest an adjustment of the pertinent param eters in the MC model.