A new method was presented for markedly suppressing the group-III interdiffusion of InGaNAs/GaAs quantum wells during thermally annealing. By inserting a thin compressively strained layer (so-called diffusion-suppressing layer) of InxdGa1-xdNydAs1-yd on either side of an InxqGa1-xqNyqAs1-yq quantum wells, both the interdiffusion of In/Ga and photoluminescence blue shift were decreased significantly and the interfaces of the InGaNAs/GaAs(N) quantum wells was much sharper after the same annealing operation. On the basis of detailed photoluminescence and X-ray diffraction investigations of InGaAs/GaAs quantum wells, InGaNAs/GaAs quantum wells with and without diffusion-suppressing layers, it was believed that the strain at interfaces played an important role in group-III interdiffusion. It was also found that a small amount of N incorporated into InGaAs/GaAs quantum wells increased the In/Ga interdiffusion. The group-V interdiffusion was observed to be much less than that of group-III.

A New Method to Suppress the In-Diffusion of InGaNAs/GaAs Quantum Wells Grown by Molecular Beam Epitaxy. C.S.Peng, T.Jouhti, E.M.Pavelescu, J.Konttinen, M.Pessa: Thin Solid Films, 2003, 428[1-2], 176-80