Silicon amorphization during ion implantation as a thermal phenomenon.

A model to understand the amorphization mechanism during ion implantation in silicon is proposed. This model ascribes the amorphization to single-recoil events, each in itself able to transfer to the lattice the energy necessary to amorphize it. The threshold energy required by this process depends in principle on the considered lattice and can be estimated with simple considerations. The proposed model is quantitatively tested by considering the implant of boron into (100) silicon, though it can be easily extended to other ions and crystal orientations. The model accounts for superlinear damage release often observed for increasing fluence and for superadditive effects occurring when collisional cascades superimpose on one another.