This intermediate report (end of the first year) summarizes the contribution of the Centre d’Electronique et de Microtechnique (CSEM) to the HyPer (“Hybrid Approach for Perovskite-Silicon Tandem Solar Cells”) project. The HyPer project aims to industrialize high-efficiency, stable 2-terminal perovskite-silicon tandem solar cells by developing scalable deposition processes for large-area devices. Its overarching goal is to raise the technology readiness level from TRL 4 to TRL 6 by demonstrating >30% power conversion efficiency on M10-size silicon heterojunction (SHJ) wafers (>250 cm² active area) using industrially relevant methods. The project focuses on adapting the hybrid two-step perovskite deposition route evaporating an inorganic scaffold followed by a dispensing of an organohalide precursor to processes compatible with large wafers and high throughput. Three scalable second-step methods (inkjet printing, slot-die coating, and close-space sublimation) will be benchmarked to ensure uniform, high-quality perovskite films on textured silicon substrates. Achieving these objectives will help overcome major bottlenecks in scaling, moving beyond small-area spin-coated devices that currently dominate record efficiencies. A second central aim is to improve the operational stability of perovskite/silicon tandems. HyPer targets <5% relative degradation after 3000 h damp-heat testing (85 °C/85% RH), 600 thermal cycles (−40 to 85 °C), and >2000 h of light soaking, ultimately aiming for <1 % absolute annual degradation outdoors in Central Europe. This will be achieved by developing more stable Formamidinium-(FA-) based perovskite formulations, suppressing defect migration and phase segregation, implementing improved transport layers (including spatial-ALD SnO2 buffers), and establishing robust glass-glass encapsulation. These material, interface, and encapsulation innovations will enhance tandem solar cell reliability and demonstrate the technology’s viability for real-world use. The project is strongly aligned with the CETPartnership Call on advanced renewable energy technologies, addressing efficiency, cost reduction, and technological sovereignty for Europe. By enabling scalable, high-performance tandem manufacturing, HyPer directly supports the deployment of low-cost clean electricity and reduces reliance on non-European PV supply chains. The consortium also integrates gender-balanced research teams and adopts an open-science approach, committing to rapid dissemination of results, open-access publications, and public release of indoor and outdoor stability data. Together, these advances establish a credible pathway toward commercial perovskite-silicon tandem modules and contribute to Switzerland and Europe’s long-term renewable energy and energy-security goals.