Monte-Carlo computer simulations based on the binary collision approximation have been employed to study the range profiles of energetic Si+ ion implantation in Si3N4/GaAs targets. Both the simulations and the experiments showed that a layer of Si3N4 deposited on the surface of GaAs substrate would reduce the range of Si+ ions in GaAs substrate effectively

but a lot of St and N atoms in the Si3N4 layer moved into GaAs substrate due to collision with the incident Si+ ions. Deposition of a layer of amorphous Si3N4 on the GaAs crystal surface followed by high energy ion implatation is a good method to obtain shallow junction and to avoid channeling effects.