Temperature effect on damage generation mechanisms during ion implantation in Si. A classical molecular dynamics study

Abstract

We have studied the temperature effect on the damage generation mechanisms in silicon, suppressing the influence of dynamic annealing. We have done dedicated classical molecular dynamics simulations to determine how the ballistic mechanism and the thermal spikes are affected by temperature. We have quantified the minimum energy required to permanently displace an atom from its lattice position by a ballistic collision. We have found that the displacement energy threshold does not change appreciably with temperature. However, when subthreshold energy is simultaneously deposited in several neighboring particles in a finite volume, i.e. when thermal spikes occur, there is an enhancement of the generation of damage with increasing temperature. In high energy recoils both mechanisms are combined, and it results in an increase of the generated damage with temperature.