Continuous carbon deposition on a silicon (1 0 0) surface, a MD simulation study

Abstract

The deposition of multiple carbon atoms on a crystalline silicon (Si) surface is modelled at 5eV energy by using molecular dynamics simulations combined with a third generation force field that includes bond breaking and formation. Force field parameters are taken from a previous work. These simulations allow for atomic scale insights into the deposition mechanisms and an easier comparison with experimental observations. The results, including distributions of implantation depth, carbon concentrations, sticking coefficients, radial distribution function, and angular distributions are compared for different incidence angles. Due to the deposition of carbon atoms inside the silicon structure, silicon carbide starts to form. The crystalline structure has been investigated for different conditions to get a better understanding of the damaging and growth mechanisms. It is found that a lot of deformation is accumulated in the area of deposition near to the surface but underneath the surface the silicon has still a more crystalline structure. The variation of the silicon (carbide) structure slightly depends on the angle of incidence. For the conditions used for these simulations, the sticking probability is always high and varies between 95% and 100%, which can be attributed to the high affinity of carbon for silicon.