Improved uniformity of SI-VB GaAs by annealing

Abstract

Ingot annealing has been applied to semi-insulating GaAs grown by the vertical Bridgman (VB) method. Significant changes in resistivity and mobility have been observed. In addition, major improvements in uniformity have also been seen. We have designed a multi-temperature ingot annealing process tailored specifically for the low dislocation density GaAs produced by the VB process. A model has been developed based on the dissolution of As precipitates and uniform redistribution of the arsenic that explains the annealing results we observe.