Semi-transparent perovskite solar cells with directly sputtered amorphous InZnSnO top cathodes for building integrated photovoltaics

We report on a low plasma damage sputtering amorphous InZnSnO (IZTO) top cathode prepared using linear facing target sputtering (LFTS) at room temperature for semi-transparent perovskite solar cells (PSCs) to be applied as building integrated photovoltaics. The effective confinement of high-density plasma between InZnO and InSnO targets by directional magnet fields and negative bias applied simultaneously on both targets led to the successful sputtering of the amorphous IZTO top cathode on the semi-transparent PSCs without plasma damage or degradation of PSC performance. At an optimal sputtering condition of the IZTO top cathode, the semi-transparent PSC showed an open circuit voltage (1.056 V), short circuit current (16.79 mA/cm²), fill factor (51.19%), and power conversion efficiency (9.081%) comparable to those of reference PSC with an Ag metal top cathode. Based on synchrotron GIWAXS and high-resolution transmission electron microscopy examinations, we suggested a possible mechanism with which to explain the plasma damage effect on the performance of PCSs while sputtering IZTO top cathode on semi-transparent PSCs.