Improvements in the heteroepitaxy of GaAs on Si

Abstract
Successful application of GaAs on Si heteroepitaxy to majority-carrier device fabrication has recently been demonstrated. However, the quality of the GaAs heteroepitaxial films is considerably below that routinely achieved for films grown on GaAs substrates. We have investigated the initial growth stages of GaAs on Si using ion channeling and double-crystal -ray diffraction, and report improvements in the growth technique leading to higher quality GaAs films. The crystalline perfection of the films was found to be critically dependent on the growth parameters of the initial GaAs buffer layer. Growth interruption after deposition of this layer, followed by an in situ annealing step (10 min at 750 °C) prior to final GaAs growth, improved both the structural and optical properties of the films.