Abstract
Oxidation of GaAs surfaces in deionized water has been investigated by using X-ray photoelectron spectroscopy with respect to the influences of dissolved oxygen, illumination intensity, carrier types, and carrier concentration. Illumination greatly accelerates the oxidation of the GaAs surface. The dissolved oxygen concentration also affects the oxidation rate; oxidation becomes dominant over dissolution of oxides for the dissolved oxygen concentration of more than 1 ppm. The carrier type as well as the carrier concentration is a determining factor of oxidation rate. The hole concentration at the GaAs surface is considered to affect the oxidation rate.
