Discovery of passivating pinholes in TOPCon solar cells paves the way for higher efficiencies

DAS Solar and Hebei University have identified two types of pinholes in TOPCon solar cells: harmful recombinational pinholes, which lack oxygen and cause carrier recombination, and beneficial passivating pinholes, which retain oxygen to enable efficient tunneling while maintaining interface passivation. Their work shows that optimizing oxide layer formation, back-surface polishing, and polycrystalline silicon deposition can increase passivating pinholes, boosting device efficiency and guiding industrial cell design.