Recently,the development of the epitaxial structures for III-V compound tandem solar cells is mature.Therefore,the internal quantum efficiency of the resulting III-V compound solar cells is more than 80%.The tandem structure should study the issues including the latticed-matched structure and the current-matched structure.The open-circuit voltage and the short-circuit current of the resulting solar cells were influenced by the latticed-matched structure and the current-matched structure,respectively.Recently,the epitaxial lattice-matched InGaP/InGaAs/Ge tandem solar cells are investigated.To further improve performances of solar cells,the InGaNAs semiconductor with 1 eV band gap is explored as the quadruple-junction tandem material.Besides,the Si substrate used to replace the Ge substrate of the tandem solar cell was also investigated.However,the conversion efficiency of the solar cells is still limited by the higher reflected sunlight from the solar cell surface.The incident light loss mainly-originated from-the 7.5% of metal coverage area associated with the conventional metal electrode and the large refraction index difference between the air and the III-V compound semiconductors.To achieve higher current extraction ability and a larger incident light absorption,the novel hybrid electrode structure was proposed to replace the conventional metal electrode structure as shown in Fig.1.The hybrid electrode structure composed of the metal contact pads and the ITO film.The metal contact pads of the hybrid electrode structure could reduce the specific contact resistance between the ITO film and the III-V compound solar cells.The transparent ITO film deposited on the metal contact pads could be used to transport carders in a way very similar to the bus-bar of the conventional metal electrode.The ITO film also possesses the antireflection function.Compared with the 125 μm interval of the conventional metal electrode,the 75 tm interval of the hybrid electrode was shorter.