Diffusion and activation mechanisms in ion-implanted GaAs

Abstract

The annealing kinetics of ion-implanted GaAs have been studied using electrical measurements from a range of donor and acceptor implants. By analysing the time and temperature dependence of the activation process, a model has been developed which predicts the sheet electrical properties after annealing. Application of the model to different ions suggests that the electrical activity in an implanted layer may be dominated by the extent to which ions form impurity-vacancy complexes. Furthermore an analysis of the time-dependent annealing mechanism indicates that the dominant diffusion process is due to a redistribution of the substrate atoms and not the implanted species itself. The paper presents a discussion of the model and its application to donor and acceptor ions in GaAs.