Abstract
Beam‐induced broadening effects in SIMS depth profiling have been studied for eight impurities (Li through Al) implanted in amorphized silicon at energies between 1 and 15 keV. Depth profiling was performed under Ar+ (⩽2.5 keV) or O (⩽3 keV) impact. In selected cases (Li, N) the effect of the probe energy has also been investigated. The measured profiles show exponential tails. The decay length γ characterizing these tails exhibits strong oscillations when plotted as a function of the atomic number of the dopant. Maxima are seen for N and O (γ ≃ 7 nm) as well as for Mg (γ ≃ 13 nm), minima for B and Na (γ ≃ 2 nm). The results suggest that the observed effects are due to a yet unpredictable combination of collisional mixing, defect‐assisted diffusion and selective sputtering.