Positron annihilation spectroscopy has been used to profile the distribution of defects following implantation of 120keV Ge~+ into (100) Si in the dose range 1x10~(10) - 1x10~(14) cm~(-2). The openvolume defect profiles can be adequately fitted assuming a simple rectangular block distribution extending to 350nm. Using anodix oxidation and etching, a procedure is described which allows details of the defect tails beyond the range of the implanted ion, usually inaccessible to positron annihilation measurements, to be determined. For a time averaged dose-rate (J_t) of 0.02#mu#A cm~(-2) and incident angle of 7deg, open-volume defects are found to exist at concentrations exceeding 10~(16) cm~(-3) at depths upto 600nm whereas the peak of the depth distribution of the implanted ions (R_p) is 76nm, measured using SIMS. When the time-average dose-rate is increased by a factor of 10, defects persist at concentrations in excess of 10~(17) cm~(-3) beyond 1#mu#m and the R_p increases to 101nm. The open-volume defect profiles are compared to those deduced from Rutherford backscattering-channeling using the fitting routine DICADA.
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