Manganese and germanium redistribution in In0.53Ga0.47 As grown by molecular beam epitaxy

The redistribution of Mn in MBE grown In0.53Ga0.47 As layers containing different combinations of Mn and Ge doping pulses and subjected to various annealing conditions has been studied by secondary ion mass spectrometry (SIMS). The results indicate that Ge has a negligible diffusivity for temperatures up to 700 °C while the diffusion coefficient of Mn is approximately inversely proportional to the local Mn concentration. Accumulation of Mn in amounts proportional to the local Ge concentration has also been observed, suggesting the formation of donor–acceptor pairs with a certain fraction of Ge in the crystal. For those Mn atoms not immobilized by pairing, the diffusion coefficient is found to be reduced by nearly two orders of magnitude by the presence of Ge in the layer with very little dependence on the spatial distribution of Ge.