The anodically treated and untreated (control sample) Au/-Cu/n-GaAs Schottky diodes have been prepared. The anodic oxidization process has been made on the n-GaAs substrate in aqueous 4C(2)H(6)O(2)+2H(2)O+0.1H(3)PO(4) electrolyte with pH=2.02. The anodic treatment has increased the barrier heights. We have obtained the laterally homogeneous barrier heights of approximately 0.79 and 0.91 eV for the anodically untreated and treated Au/n-GaAs SBDs, respectively, and 0.67 and 0.91 eV for the Cu/n-GaAs SBD eV respectively when accounting for the image-forge effect only. Thus, the barrier height has been increased by at least 110 and 240 meV for Au/n-GaAs and Cu/n-GaAs SBDs, respectively. (C) 2001 Kluwer Academic Publishers.