The phenomenon of B up-hill diffusion during the low-temperature annealing of ultra-shallow ion-implanted junctions in Si was investigated. It was shown that the effect was enhanced by pre-amorphization, and that an increase in the depth of the pre-amorphized layer reduced up-hill diffusion in the high-concentration portion of B profile, while increasing transient enhanced diffusion in the tail. The data demonstrated that the magnitude of the up-hill diffusion effect was determined by the proximity of B and implant damage to the Si surface.

Boron Up-Hill Diffusion during Ultra-Shallow Junction Formation. R.Duffy, V.C.Venezia, A.Heringa, T.W.T.Hüsken, M.J.P.Hopstaken, N.E.B.Cowern, P.B.Griffin, C.C.Wang: Applied Physics Letters, 2003, 82[21], 3647-9