- Tan, T.Y. and Yu, S. and Gosele, U., Atomistic mechanisms of dopant-induced multiple quantum well mixing and related phenomena,
Opt. Quantum Electron. (UK), vol. 23 no. 7
pp. 863 - 81 .
(last updated on 2007/04/10)
The authors 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
aluminium compounds;chemical interdiffusion;diffusion in solids;Fermi level;gallium arsenide;III-V semiconductors;impurities;interstitials;self-diffusion in solids;semiconductor quantum wells;vacancies (crystal);