GAAS SURFACE PASSIVATION BY DEPOSITION OF AN ULTRATHIN INP-RELATED LAYER

A few-atomic-layer deposition of InP-related compounds on a GaAs surface greatly improves the surface properties. Tenfold enhancement in the photoluminescence intensity is observed at the GaAs band edge, which indicates a reduction in the surface recombination. Relaxation of the surface pinning, which results in photoluminescence intensity enhancement, is observed by x-ray photoelectron spectroscopy. Based on the results, we propose a novel concept of surface passivation by atomic-layer deposition, where the surface band structure of GaAs is modulated by the ultrathin strained layer.