The evolution of the electrically active B fraction was measured in B-implanted material, and was also calculated by using atomistic simulations. The effect of implanting 40keV B to a dose of 2 x 1014/cm2 was studied during post-implantation annealing at 800C. The results revealed 25% B activation at annealing times of up to 10s. This slowly increased with time (up to 40% after 1000s), in agreement with the proposed model. It was concluded that B clustering occurred, in the presence of a high interstitial concentration, in the very early stages of annealing. Consequently, B clustering was not avoided by performing short-term or low-temperature annealing. The total dissolution of B clusters involved thermally generated Si interstitials and therefore required long-term, or high-temperature, annealing.

Activation and Deactivation of Implanted B in Si L.Pelaz, V.C.Venezia, H.J.Gossmann, G.H.Gimer, A.T.Fiory, C.S.Rafferty, M.Jaraíz, J.Barbolla: Applied Physics Letters, 1999, 75[5], 662-4