Published online by Cambridge University Press: 22 February 2011
A study of the recently observed double-height Si(001) step formation by sputtering with low-energy Xe ions is presented. The modeling of the process has been separated in two stages: (i) Molecular dynamics (MD) simulations of the interaction of 225 eV Xe ions with Si(001) surfaces and (ii) calculation of the step kinetics by reaction-diffusion equations. It is found that a single Xe ion produces surface vacancies arranged in one cluster, some adatoms and on the average one sputtered atom. For adjacent terraces on a vicinal Si(001)-(2 × 1) surface separated by SA- and SB-steps, respectively, the adatom diffusion as well as their attachment and detachment at steps and vacancy clusters determines the kinetics of the steps and results in double-height Si(001) steps.