CC BY 4.0Jakob, LeonieLeonieJakobTutsch, LeonardLeonardTutschHatt, ThibaudThibaudHattWestraadt, JohanJohanWestraadtNgongo, SinoyoloSinoyoloNgongoGlatthaar, MarkusMarkusGlatthaarBivour, MartinMartinBivourBartsch, JonasJonasBartsch2023-11-022023-11-022023Note-ID: 00008896https://publica.fraunhofer.de/handle/publica/452483https://doi.org/10.24406/publica-210110.1002/solr.20230041810.24406/publica-2101Herein, a novel strategy is introduced to reduce the consumption of scarce materials in silicon heterojunction solar cells by combining approaches for Ag replacement in the metallization and a reduction of the indium tin oxide layer thickness: a Ti layer deposited by physical vapor deposition serves both as the contact layer of a copper-based metallization and after electrochemical oxidation as capping layer enabling the use of a thinner transparent conductive oxide. Further, the TiOx layer can build an encapsulation layer. While oxygen evolution and metal dissolution are found to be critical side reactions, a nonaqueous electrolyte is found in which these reactions can be avoided. The application on silicon heterojunction solar cells shows promising first results, exhibiting a short circuit current density of 35 mA cm-2 and a cell efficiency of close to 21% despite nonoptimized layer thicknesses.enjournal article