Point defects, diffusion mechanisms, and superlattice disordering in GaAs-based materials

We discuss mechanisms of Ga self-diffusion and impurity diffusion in GaAs, and of disordering enhancement in GaAs/AlGaAs superlattices. Ga self-diffusion and Ga-Al interdiffusion are governed by VGa3- under instrinsic and n-doping conditions, and by IGa2+ under heavy p-doping conditions. The responsible mechanisms for enhancing superlattice disordering is the Fermi-level effect for the n-dopants Si and Te, and are the combined effects of the Fermi-level and the dopant diffusion induced non-equilibrium point defects for the p-dopants Zn and Be. For n-type GaAs the donor Si atoms diffuse primarily also via VGa3- for p-type GaAs the interstitial-substitutional impurities Zn and Be diffuse via the kick-out mechanism and induce an IGa2+ supersaturation and undersaturation, respectively, under indiffusion and out-diffusion conditions.

Duke Authors

Cited Authors

  • Tan, TY; Goesele, U; Yu, S

Published Date

  • 1991

Published In

  • Proceedings - The Electrochemical Society

Volume / Issue

  • 91 / 4

Start / End Page

  • 195 - 226

Citation Source

  • SciVal