Study of Si-Implanted and Thermally Annealed Layers of Silicon by Using X-ray Grazing Incidence Methods

This paper reports on the study of structural modifications induced by the implantation process and by the subsequent thermal annealing in near-surface layers of Si single crystals implanted with Si$\text{}^{2+}$ ions of energy 140 keV and doses from 1×10$\text{}^{15}$ to 1× 10$\text{}^{16}$ ions/cm$\text{}^{2}$. The grazing incidence X-ray diffraction and X-ray reflectivity measurements were applied to determine the thickness and structural composition of the damaged layers. The fitted electron density profiles indicated an existence of an interfacial layer with density higher than the density of Si matrix or near-surface oxide layer. Formation of polycrystalline phases of silicon and silicon oxides is discussed in dependence on the conditions of annealing treatment and implantation dose.