Epilayers of B-doped material were grown by using molecular beam epitaxy with an elemental B source (up to 2 x 1020/cm3) in order to elucidate profile control at growth temperatures which ranged from 450 to 900C. Precipitation and surface segregation effects were observed at dopant levels of 2 x 1020/cm3 and growth temperatures of more than 600C. At growth temperatures below 600C, excellent profile control was achieved (with complete electrical activation) at a concentration of 2 x 1020/cm3. These values corresponded to the optimum molecular beam epitaxial growth conditions for a range of Si/SiGe heterostructures.

C.P.Parry, S.M.Newstead, R.D.Barlow, P.Augustus, R.A.A.Kubiak, M.G.Dowsett, T.E.Whall, E.H.C.Parker: Applied Physics Letters, 1991, 58[5], 481-3