Paper eintragenIt was shown that the Si-doping of quantum-well materials to 1019/cm3 promoted a time- and temperature-dependent diffusion process which was related to group-III vacancy formation. The effect of the formation of such vacancies upon subsequent interdiffusion was modelled and was shown to reproduce variations, in the diffusion coefficient as a function of depth, without invoking a Fermi-level model. Experiments which were performed on layers that were doped to between 1017 and 1018/cm3 did not reveal an enhanced interdiffusion; contrary to the predictions of the Fermi-level model. Other results suggested that the reason for this was that interdiffusion in III-V materials was not governed by thermal equilibrium vacancy concentrations but rather by the vacancy concentrations which were grown into the substrate materials. It was demonstrated that the position of the Fermi level played no role in III-V intermixing.

Z.H.Jafri, W.P.Gillin: Journal of Applied Physics, 1997, 81[5], 2179-84