It was recalled that H diffusion in III-V semiconductors usually led to a reduction in the active dopant concentration, and to an increase in the free carrier mobility. It was considered that this neutralization of the dopants was a result of the formation of a complex which included H and the dopant atom. The microscopic structure was deduced from a detailed analysis of the infra-red local vibrational modes of H and the dopants. Modelling of D diffusion profiles Zn-doped material indicated the presence of a H donor level at 1.1eV below the conduction band minimum. The D diffusion behavior in Si-doped GaAs or Si-doped AlxGa1-xAs indicated that the acceptor level of H was slightly resonant in the GaAs conduction band, and became localized in the band gap of alloys when x was greater than 0.08.

J.Chevallier, B.Pajot: Materials Science Forum, 1992, 83-87, 539-50