Flow-Rate Modulation Epitaxy of GaAs

Abstract

We propose a flow-rate modulation epitaxy method which yields high-purity GaAs layers with improved growth rate controllability. This method is based on an alternate gas flow of triethyl gallium (TEG) and arsine (AsH 3 ) by using hydrogen carrier gas. The most characteristic point of this method is that a very small amount of AsH 3 is added during the TEG flow period. This small amount of AsH 3 suppresses the formation of arsenic vacancies near the growing surface, and thus reduces the incorporation of impurity atoms. As a result, we could obtain high purity GaAs layer at relatively low growth temperatures.