An electrode structure comprises a semiconductor junction comprising an n-type semiconductor layer and a p-type semiconductor layer; a hole exnihilation layer on the p-type semiconductor layer; and a transparent electrode layer on the hole exnihilation layer. The electrode structure further comprises a conductive layer between the hole exnihilation layer and the transparent electrode layer. In the electrode structure, one or more of the hole exnihilation layer, the conductive layer and the transparent electrode layer may be formed by an atomic layer deposition. In the electrode structure, a transparent electrode formed of a degenerated n-type oxide semiconductor does not come in direct contact with a p-type semiconductor, and thus, annihilation or recombination of holes generated in the p-type semiconductor cam be reduced, which increases the carrier generation efficiency. Further, the electric conductivity of the transparent electrode is increased by the conductive layer, which improves electrical characteristics of a device.