Diffusion of implanted beryllium in n- and p-type GaAs

Abstract
The diffusion of ion-implanted Be in GaAs is studied by comparing the diffusion of implanted Be in undoped GaAs and in GaAs uniformly doped with Zn or Si. The Si-doped sample exhibits much less Be diffusion compared to the undoped case, while the Zn-doped sample shows much more Be diffusion. The diffusion in the doped substrate cases can be simulated with a constant Be diffusivity, as opposed to a concentration-dependent diffusivity in the undoped case. The results are consistent with the substitutional-interstitial diffusion mechanism, which predicts a diffusivity that is dependent on the net hole concentration.