Damage profiles in as-implanted silicon: Fluence dependence

[100] silicon wafers were implanted in random geometry and RT with process parameters in the following ranges: ion atomic number from 11 to 28 (B, N and Si ions), energy from 50 keV to 0.7 MeV, fluence from 2 X 10(12) to 3 X 10(15) cm(-2) and dose rate less than or equal to 2 X 10(12) cm(-2) s(-1). The damage profiles, measured by X-rays as strain profiles, confirmed the well-known effect that the damage accumulation is a non-linear phenomenon with fluence and gave new information about the damage evolution. While the ion projected range is almost constant, the damage projected range shifts in depth reaching a maximum value with increasing fluence. The damage accumulation on the front and on the tail edges of the disorder profile shows an asymmetric trend with respect to the profile of the energy released in nuclear collisions. These phenomena enhance with the lowering of the ion atomic number and/or increase of the ion energy.