A focussed ion beam system was applied to study the dose dependence of the shape of Ge channeling implantation profiles at two very different dose rates (1018 and 1011/cm2s), and for implantation temperatures of 250C and room temperature. A simple model for the buildup of radiation damage was developed to describe the dechannelling effect of defects formed during ion bombardment. The use of this model in atomistic computer simulations yields Ge depth profiles which agree well with measured data. The lifetime of ion-beam-induced defects at 250C was estimated to be of the order of 100s. At room temperature, some defect relaxation was found between 10µs and 100s after ion impact.

Influence of Dose Rate and Temperature on Ion-Beam-Induced Defect Evolution in Si Investigated by Channelling Implantation at Different Doses. M.Posselt, L.Bischoff, J.Teichert: Applied Physics Letters, 2001, 79[10], 1444-6