Nitrogen-induced suppression of an indium-gallium interdiffusion in InxGa1−xAs1−yNy∕GaAs multiple-quantum wells

In this letter, we present x-ray diffraction (XRD) measurements on as-grown and annealed (In,Ga)As∕GaAs and (In,Ga)(As,N)∕GaAs multiple-quantum wells grown on GaAs (001) substrates. Concerning the (In,Ga)As material system, we observe a shift of the envelope in the XRD curves of the annealed samples. This shift can be explained by an indium–gallium interdiffusion across the (In,Ga)As∕GaAs interfaces. A diffusion model is employed to simulate the envelope shift which yields an activation energy of 0.8 eV. Regarding the XRD curves of the (In,Ga)(As,N) samples, no annealing-induced shift of the envelope is observed. Hence, we conclude that the incorporation of nitrogen suppresses the indium–gallium interdiffusion. Several models are discussed to explain this observation.