The effect of stepwise postimplantation annealing on the composition and structure of silicon surface layers implanted with alkali metal ions

The dynamics of changes in the crystal structure and in the elemental and chemical composition of Si surface layers implanted with Na$^+$, Rb$^+$, and Cs$^+$ ions in the process of stepwise annealing under different temperature conditions has been studied. It is shown that, on the surface implanted with Na$^+$ ions, a NaSi$_2$ film is formed after annealing it at a temperature of $T$ = 900 K, a single-layer NaSi$_2$ coating is formed at $T$ = 1000 K and the surface and near-surface Si layers are completely cleansed of the atoms of the alloying element, oxygen, and carbon at $T$ = 1100 K.