Epitaxial growth on InP substrates etched with methane reactive ion etching technique

InP substrates have been etched by RIE using a mixture of methane, argon and hydrogen. With angle-resolved photoelectron spectroscopy, the authors show that, after etching, a nonstoichiometric layer is created at the surface: this layer is phosphorus depleted and extends to a thickness varying from 10 to 40 AA according to the RIE conditions. A heat treatment under P₂ atoms is able to restore the surface crystallinity permits the growth of high-quality epilayers.