New interdiffusion data on GaAs/AlAs superlattices led to the conclusion that Ga self-diffusion in GaAs involved triply negatively charged Ga vacancies under intrinsic and n-doped conditions. The mechanism of Si-enhanced superlattice disordering was the Fermi-level effect, which increased the concentrations of the charged point defect species. With respect to the effect of Be and Zn p-type dopants, the Fermi level effect had to be considered together with dopant diffusion-induced Ga self-interstitial supersaturation or undersaturation. The self-diffusion of Ga under heavy p-doping conditions was governed by positively charged Ga self-interstitials.

T.Y.Tan, U.Gösele: Applied Physics Letters, 1988, 52[15], 1240-2