Electrical activation kinetics for shallow boron implants in silicon

Silicon implanted with boron at 1015 cm−2 dose and energies from 500 eV to 1 keV were annealed over wide variations in temperature and time to obtain process kinetics and thermal activation energies for shallow junction formation. Diffusion depths and carrier densities were determined by modeling sheet electrical transport. The thermal activation energy for the mean time to produce electrical activation is found to be 5.1±0.1 eV, while for the mean diffusivity it is found to be 4.1±0.1 eV. The 1 eV difference expresses quantitatively the particular advantage of spike thermal anneals at temperatures above 1000 °C.