Screen printing for silicon photovoltaics at terawatt scale: Trends, challenges, and opportunities

Screen printing has been the dominant metallization technology for silicon solar cells since the 1980s. Within two decades, printed finger widths were reduced from ∼100 μm to ∼10–15 μm in mass production and ∼5 μm at R&D level. This review analyzes the economic drivers, technological catalysts, and milestones that have shaped screen-printed solar cell metallization. We first examine the proposed goal of < 2 mg/Wp silver consumption for sustainable terawatt-scale PV production by calculating various scenarios with updated assumptions. We derive a two-phase learning curve for finger width vs cumulative PV capacity, with learning rates of 12% (2008–2012) and 29% (2013–2024). We show how silver price volatility (peaks in 2008 and 2011) and interconnection transitions from three busbars to multi-busbar/multi-wire concepts catalyzed rapid fine-line innovations, reducing silver consumption while increasing cell performance. We discuss disruptive innovations such as knotless fine-mesh screens, laser-structured polyimide screens, and laser-enhanced contact optimization and their impact on fine-line printing. We quantify the learning rate of silver's module-price share, finding a 21.7% reduction per capacity doubling. However, silver's module-price share has risen since 2024 due to growing market share of TOPCon and rising silver prices. Finally, we outline pathways toward sustainable low-silver PV metallization, including stencil printing as an alternative to screen printing and the growing role of copper-, nickel-, or aluminum-containing pastes.