MEIS study of As implantation in O or N pre-implanted Si(0 0 1)

We have used medium energy ion scattering (MEIS) to study dopant (arsenic, As) behavior in vacancy-rich layers on Si(1 0 0). The vacancy-rich layers were generated by implantation at 400 °C of 240 keV O₂⁺ or N₂⁺ ions and a dose of 2.5 × 10¹⁶ cm^-2. The As dopant was introduced by implanting at 20 keV at room temperature to a dose of 5 × 10¹⁴ cm^-2, followed by either rapid thermal annealing (RTA) or furnace annealing (FA). The results showed very good Si crystal quality after both thermal treatments, especially when compared to otherwise identical samples without pre-implanted O or N. Differences between the O and N pre-implanted samples were also observed, suggesting the occurrence of chemical effects in the crystal recovery and dopant diffusion processes.