Crystallographic nature and formation mechanisms of highly irregular structure in implanted and annealed Si layers

The state of the structure in (111)- and (001)-orientated Si single crystals was studied by backscattering of channelled He+ ions, transmission electron diffraction and electron microscopy techniques after Ar+, Si+ and P+ ion implantation and high temperature annealing. The formation processes of an anomalously high residual disordering in recrystallised layers were shown to be based on the deformation twinning mechanism which is unique for all types of ions. Deformation twinning in implanted layers is induced by the internal stresses caused by the action of two factors. The first is due to the chemical nature of an impurity to be implanted, particularly, to a blistering effect in the case of Ar+ implantation. The spatial inhomogeneity of the amorphized layer structure is responsible for the second factor. The role of specimen crystallographic orientation as well as the role of implantation temperature in recrystallization processes of implanted layers are discussed.