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In this paper,we investigate and compare three different fine line printing techniques for the silver front side metallization of industrial-type silicon solar ceils: single print,dual print and print-on-print.We produce solar cells using the same aperture of 40 μm and about 92 fingers and obtain finger widths below 60 μm for all three approaches.The print-on print process achieves the highest finger heights of 20 μm after firing but with quite strong finger height variation.In contrast,the dual printed fingers have a very fiat surface with a finger height of 14.5 μm which leads to the highest cross-section area of 530 μm2 of the three techniques.The single print shows the lowest cross-section area of 390 μm2 due to the lowest average finger height.The measured finger line resistance correlates with the finger cross-section area.The dual print allows us to use a non-firing through bus bar paste which increases the Voc by 2 mV and hence achieves the highest efficiency of 19.1% using full-area Al-BSF cells.Also,in a recent batch of PERC solar cells,we have achieved efficiencies up to 19.8% with a record low front side Ag paste consumption of 67.7mg per wafer due to a new segmented bus bar design used in combination with dual print technique.