The research on efficiency gain of TOPCon solar cells based on UV irradiation

The Tunnel Oxide Passivated Contact (TOPCon) technology has emerged as the dominant technological pathway following Passivated Emitter and Rear Cell. It has established hundreds of gigawatt-scale production ecosystem, yet the photovoltaic industry faces pressure from overcapacity and homogenized competition. Therefore, exploring low-cost, production-line-compatible process optimizations and technological innovations to further unlock the efficiency potential of TOPCon cells is of critical importance for enhancing corporate competitiveness and promoting sustainable industrial development. This study aims to investigate the feasibility of ultraviolet (UV) irradiation on TOPCon cells as a low-cost efficiency-boosting pathway. This research investigates the effects of UV irradiation on the TOPCon cells manufacturing process at different precursor stages, aiming to elucidate the underlying physical mechanisms for efficiency improvement. It reveals that the efficiency gain of the UV process primarily stems from the significant enhancement in passivation quality. This improvement is attributed to the effective breaking of Al–OH bonds in the AlOX layer by UV photon energy. This approach reaches more effective hydrogen passivation, thereby strengthening bulk and interface passivation and achieving higher conversion efficiency. Validation experiments on a small-scale solar cells' batch show an average absolute efficiency increase in 0.09% after UV irradiation, confirming the feasibility and effectiveness of this technique.