The redistribution of Be during rapid thermal annealing following the growth of layers via gas-source molecular beam epitaxy, was studied by using secondary ion mass spectrometry. The specimens consisted of an 0.2μ Be-doped (3 x 1019/cm3) (In0.73Ga0.27)(As0.58P0.42) layer which was sandwiched between 0.5μ undoped (In0.73Ga0.27)(As0.58P0.42) layers. A kick-out model for the substitutional-interstitial diffusion mechanism, which involved neutral interstitial Be species and positively charged group-III self-interstitials, was proposed in order to explain the observed depth profiles. A set of parameters was suggested which was claimed to describe Be diffusion in quaternary epitaxial layers at 700 to 900C.

A Study of Be Diffusion in InGaAsP Layers Grown by Gas-Source Molecular Beam Epitaxy S.Koumetz, K.Ketata, M.Ketata, J.Marcon: Journal of Physics D, 1998, 31[24], 3421-7