Redistribution of ytterbium and oxygen in annealing of silicon layers amorphized by implantation

The redistribution of ytterbium and oxygen was studied in silicon layers that were implanted with 1-MeV Yb + ions at a dose of 1×10 14 cm −2 , which exceeds the amorphization threshold, and 135-keV O + ions at a dose of 1×10 15 cm −2 and that were subsequently annealed at 620 and 900°C. The redistribution of Yb is due to segregation at the interface between the amorphous and single-crystal layers in solid-phase recrystallization of the buried amorphized layer. The redistribution of oxygen and its accumulation in regions with the highest concentration of Yb is associated with oxygen diffusion and the formation of YbO n complexes with n varying from 1 to 6. The parameters characterizing the dependence of the Yb segregation coefficient on the thickness of the recrystallized layer and the formation of YbO n complexes were determined.