Atomistic mechanisms of dopant-induced multiple quantum well mixing and related phenomena

We discuss mechanisms of Ga self-diffusion and impurity diffusion in GaAs, and of layer mixing enhancement in GaAs/AlGaAs multiple quantum wells (MQWs). Ga self-diffusion and Ga-Al interdiffusion are governed by the triply negatively charged Ga vacancies, VGa3-, under intrinsic and n-doping conditions, and by doubly positively charged Ga self-interstitials, IGa2+, under heavy p-doping conditions. The mechanisms responsible for enhancing MQW mixing are the Fermi-level effect for the n-dopants Si and Te, and the combined effects of the Fermi-level and the dopant diffusion-induced nonequilibrium 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 kickout mechanism and induce a supersaturation and an undersaturation in the concentrations of IGa2+, respectively, under indiffusion and outdiffusion conditions. © 1991 Chapman and Hall Ltd.

Full Text

Duke Authors

Cited Authors

  • Tan, TY; Yu, S; Gösele, U

Published Date

  • 1991

Published In

Volume / Issue

  • 23 / 7

Start / End Page

  • S863 - S881

International Standard Serial Number (ISSN)

  • 0306-8919

Digital Object Identifier (DOI)

  • 10.1007/BF00624976

Citation Source

  • SciVal