BE DIFFUSION MECHANISMS IN INGAAS DURING POSTGROWTH ANNEALING

Be diffusion during post-growth annealing has been studied in InGaAs e pitaxial layers, grown between two undoped InGaAs layers. To explain t he observed concentration profiles and related diffusion mechanisms, a general substitutional-interstitial model is proposed. On the one han d, a simultaneous diffusion by dissociative and kick-out models is sug gested and, on the other hand, the Fermi-level effect is used to expla in the functional dependence change of the effective diffusion coeffic ient of beryllium species with its concentration. The concentration de pendent diffusivity has also been covered to perform an improved data fitting of Be diffusion profiles. (C) 1995 American Institute of Physi cs.