DEFECT PRODUCTION IN SI(100) BY F-19, SI-28, AR-40, AND XE-131 IMPLANTATION AT ROOM-TEMPERATURE

We used x-ray double-crystal diffractometry and MeV He-4 channeling spectrometry to study quantitatively the damage produced in Si(100) at room temperature by 230-keV F-19, 230-keV Si-28, 250-keV Ar-40, or 570-keV Xe-131 implantation. The measured defect concentration and the perpendicular strain have the same depth profile, and both are depleted near the surface compared to the Frenkel pair concentration calculated from computer simulation. The perpendicular strain is proportional to the defect concentration with a coefficient of B approximately 0.01 common to all implanted species. The maximum value of the perpendicular strain and of the defect concentration rises nonlinearly with the dose for all species. The damage produced by different implanted species depends on the dose in approximately the same way save for a scaling factor of the dose. In the regime of low damage, the strain and the defect concentration rise linearly with increasing dose. The slope of this rise with dose increases with the square of the Frenkel pairs produced per unit dose of incident ions, as calculated from computer simulations. This fact means that stable defects produced by room-temperature implantation in Si(100) cannot be predicted by a linear cascade model.