Study of acceptor centers in GaAs after high temperature annealing. Experiments and calculation

A study of the kinetics of the conduction conversion of semi-insulating (SI) GaAs at high temperature annealing above 800 °C has been made. Undoped semi-insulating GaAs samples have been submitted to anneal/quench with various annealing temperatures (900–1100 °C) and various annealing times (30–180 min). It is shown, that (SI) GaAs crystals are converted to p-type. Using the Hall effect technique, the acceptor concentration is measured at room temperature for each annealing time and each annealing temperature. The present analysis indicates, that the acceptor concentration increases with increasing annealing time. In order to study this conversion and to give a model for acceptor centers generated, a proposed model based on a simple kinetic is used to fit the variation of the acceptor concentration as a function of the annealing time. However, from the best fit of the experimental data using the proposed model, the migration energy is determined.