“…The resistivity of ITO and fluorine-doped tin oxide (FTO) films, both of which are TCO commonly used for solar cells, is approximately 10 −4 -10 −3 Ωcm. [35][36][37] This result suggests that AlGaN can be used as a conductive film in photovoltaic devices. Hence, as the electrical conductivity is high enough, ITO/FTO-free perovskite solar cells are expected to be realized, as has been reported for GaN.…”