Deactivation of low energy boron implants into preamorphized Si after non-melt laser annealing with multiple scans

Activation/deactivation of 500eV B implants in pre-amorphised Si after non-melt laser annealing with multiple scans at 1150°C and isochronal rapid thermal post-annealing has been investigated. Under the thermal conditions used for non-melt laser at 1150°C, a substantial residue of end-of-range defects remained after 1 laser scan, evidenced by end-of-range defect decoration by B atoms after 700°C post-annealing and by transient enhanced diffusion after 800°C post-annealing. Dramatic boron deactivation is also observed after post-annealing the 1-scan samples. Most of these features were not present in samples receiving 5 or 10 laser scans, indicating that the end-of-range defects had been stabilised or dissolved within 5 and 10 scans. The results show that the detrimental effects of end-of-range defects can be removed during non-melt laser annealing and is therefore an achievable method for stabilisation of highly activated B profiles in pre-amorphised Si.