DEEP (1–10 μ) PENETRATION OF ION‐IMPLANTED DONORS IN SILICON

Deep penetration of donors has been observed as a result of 20‐kV Sb ion implantations into 〈110〉‐ and 〈111〉‐oriented, high‐resistivity silicon. The density profiles were measured by a capacitance‐voltage method. The deep penetrating tail was found to be independent of such experimental parameters as temperature of implant (for T ≥ 300°C), orientation, annealing, and surface condition; and to empirically follow a N ∝ (x + B)2.2 dependence over four orders of magnitude (B ≈ 0.15 μ). This component has not been observed previously in silicon and has a different dependence on implantation parameters and a different functional form than that observed in ion channeling.