EFFECTS OF DISSOLVED-OXYGEN IN A DEIONIZED WATER-TREATMENT ON GAAS SURFACE

This article presents a new passivation method with an As and/or hydrogenated As layer on a GaAs surface. X-ray photoelectron spectroscopy was employed to investigate the influences of dissolved oxygen on a GaAs surface during the de-ionized water treatment. It is shown that reduction of dissolved oxygen in de-ionized water accelerates the removal of Ga and As oxides from the surface, and that the de-ionized water treatment in an extremely low concentration of dissolved oxygen produces arsenic and/or hydrogenated arsenic layer due to the liberation of Ga atoms near the surface. These phenomena are discussed based on the chemical reaction between the GaAs surface and dissolved oxygen in de-ionized water. The arsenic and hydrogenated arsenic layer is available for preserving the oxide-free and damage-free GaAs surface.