Optical and structural properties of anodized AlxGa1 − xAs layers

The optical and structural properties of anodized AlxGa1 − xAs films were investigated by using optical reflectance, X-ray photoemission and Auger electron spectroscopy (XPS and AES). It was found that the anodization process occurs progressively from the surface to the bulk of AlxGa1 − xAs and the formed oxidation film comprises mainly oxides of Al and Ga together with a relatively small amount of As. The refractive indexes of the anodized Al0.8Ga0.2As film and Al0.8Ga0.2As film itself were deduced to be about 1.80 and 3.25, respectively, indicating that the anodization film is desirable for antireflection coating of the surface of AlxGa1 − xAs/GaAs solar cells.