It was pointed out that the characteristic features of Zn diffusion in GaAs substrates and GaAs/AlGaAs superlattices could be explained in terms of a kick-out mechanism in which the doubly positively charged Ga self-interstitial governed Ga self-diffusion. Such characteristics included a square-law dependence of the Zn diffusivity upon its own background concentration under Zn iso-concentration diffusion conditions, various Zn in-diffusion profiles, much lower diffusivities of Zn under out-diffusion conditions than under in-diffusion conditions, and a huge enhancement of Zn in-diffusion during GaAs/AlGaAs superlattice disordering. It was found that the Longini mechanism was able to explain most of these features.

S.Yu, T.Y.Tan, U.Gösele: Journal of Applied Physics, 1991, 69[6], 3547-65