GaAs Surface Cleaning with HCl Gas and Hydrogen Mixture for Molecular-Beam-Epitaxial Growth

Abstract
GaAs surface cleaning with a hydrogen chloride gas and hydrogen mixture prior to molecular-beam-epitaxial growth has been investigated as a means of reducing the carrier depletion at the substrate-epitaxial layer interface. Reactive gas etching was performed at a substrate temperature of 500°C. The amount of carrier depletion, measured by a capacitance-voltage carrier profiling technique, decreased significantly from 1.2×1012 cm-2 to less than 1×1010 cm-2.