Damage characteristics of low-temperature BSi molecular ion implantation in silicon

This study investigates the damage characteristics of BSi molecular ions implanted into silicon at liquid nitrogen temperature (LT) and room temperature (RT). 〈1 0 0〉 single-crystal silicon specimens tilted 7° were implanted with 77 keV BSi molecular ions for various ion fluences (1 × 1013-2 × 1015 cm−2) and then rapid thermal annealed at 1050 °C for 25 s in nitrogen ambient. The SRIM Monte-Carlo computer code was adopted to calculate theoretical damage depth profiles. Raman scattering spectroscopy (RSS) was employed to experimentally characterize damage behavior. It is found that the existence of crystalline and amorphous phases in the specimens can be clearly identified by the longitudinal and transverse optical phonon Raman peaks, respectively, in terms of peak intensity, peak position, area under the peak, and full-width at half-maximum (FWHM) of the peak. The as-implanted results reveal that LT leads to a greater amount of implantation-induced damage than RT does. However, the as-annealed results show that the amount of residual damage in the LT specimen is only slightly smaller than it is in the RT specimen.