Bett, Alexander J.Alexander J.BettWinkler, KristinaKristinaWinklerBivour, MartinMartinBivourCojocaru, LudmilaLudmilaCojocaruKabakli, Özde SeymaÖzde SeymaKabakliSchulze, Patricia S. C.Patricia S. C.SchulzeSiefer, GeraldGeraldSieferTutsch, LeonardLeonardTutschHermle, MartinMartinHermleGlunz, Stefan W.Stefan W.GlunzGoldschmidt, Jan ChristophJan ChristophGoldschmidt2022-03-0629.2.20202019https://publica.fraunhofer.de/handle/publica/26123510.24406/publica-r-26123510.1021/acsami.9b17241Perovskite silicon tandem solar cells have the potential to overcome the efficiency limit of single-junction solar cells. For both monolithic and mechanically stacked tandem devices, a semi-transparent perovskite top solar cell, including a transparent contact, is required. Usually, this contact consists of a metal oxide buffer layer and a sputtered transparent conductive oxide. In this work, semi-transparent perovskite solar cells in the regular n-i-p structure are presented with tin-doped indium oxide (ITO) directly sputtered on the hole conducting material Spiro-OMeTAD. ITO process parameters such as sputter power, temperature, and pressure in the chamber are systematically varied. While a low temperature of 50 °C is crucial for good device performance, a low sputter power has only a slight effect, and an increased chamber pressure has no influence on device performance. For the 5 × 5 mm2 perovskite cell with a planar front side, a 105 nm thick ITO layer with a sheet resistance of 44 O sq-1 allowing for the omission of grid fingers and a MgF2 antireflection coating are used to improve transmission into the solar cells. The best device achieved an efficiency of 14.8%, which would result in 24.2% in a four-terminal tandem configuration.enPhotovoltaikNeuartige Photovoltaik-TechnologienFarbstoff- und PerowskitsolarzellenTandemsolarzellen auf kristallinem Silicium621628697journal article