Range and range straggling of oxygen implanted into silicon at energies between 2 and 20 MeV

Oxygen profiles in silicon implanted with energies between 2 and 20 MeV by means of a Tandem accelerator have been investigated with a microprobe after bevelling the sample surface. It is shown that the measured profiles correspond to the implantation profiles when the microprobe is operated with a well focussed 2 keV electron beam. The projected ion ranges and the profiles thus obtained are compared with theoretical profiles which have been calculated by a Monte Carlo simulation of the stopping procedure. Takingk=1.30k _LSS for the electronic stopping coefficient in the LSS region up to 2.55 MeV and a constant value of 162 eV/Å for the electronic stopping at higher energies the calculation yields satisfactory range estimates, whereas the range straggling is systematically too small up to 13% in comparison with the experimental results.