Defect clustering during ion irradiation of GaAs: Insight from molecular dynamics simulations

Defect formation in compound semiconductors such as GaAs under ion irradiat ion is not as well understood as in Si and Ge. We show how a combination of ion range calculations and molecular dynamics computer simulations can be used to predict the atomic-level damage structures produced by MeV ions. Th e results show that the majority of damage produced in GaAs both by low-ene rgy self-recoils and 6 MeV He ions is in clusters, and that a clear majorit y of the isolated defects are interstitials. Implications of the results fo r suggested applications are also discussed. (C) 2001 American Institute of Physics.