The path towards efficient wide band gap thin-film kesterite solar cells with transparent back contact for viable tandem application

Wide band gap thin-film kesterite solar cell based on non-toxic and earth-abundant materials might be a suitable candidate as top for tandem configuration in combination with crystalline silicon bottom cell. For this purpose parameters we have extracted from electrical optical characterization techniques of Cu2ZnGeSe4 absorbers cells, model has been developed to describe the efficiency limitations investigate different possible configurations transparent back contact four-terminal application. Furthermore, studied performance view transparency engineering. Our detailed analysis shows that > 14%, range 1.5–1.7 eV above 80% at sub-band gaps photons energies are required achieve higher than single