An investigation was made of the effect of excimer laser annealing (ELA) on transient enhanced diffusion and activation of B implanted in Si during subsequent rapid thermal annealing. It was observed that ELA with partial melting of the implanted region caused reduction of transient enhanced diffusion in the region that remained solid during ELA, where the diffusion length of B was reduced by a factor of ~4 as compared to the as-implanted sample. This was attributed to several mechanisms such as liquid-state annealing of a fraction of the implantation induced defects, introduction of excess vacancies during ELA, and solid-state annealing of the defects beyond the maximum melting depth by the heat wave propagating into the Si wafer. The ELA pre-treatment provided a substantially improved electrical activation of B during subsequent RTA.

The Effect of Excimer Laser Pretreatment on Diffusion and Activation of Boron Implanted in Silicon. E.V.Monakhov, B.G.Svensson, M.K.Linnarsson, A.La Magna, M.Italia, V.Privitera, G.Fortunato, M.Cuscunà, L.Mariucci: Applied Physics Letters, 2005, 87[19], 192109 (3pp)