Plating Metallization for Bifacial i-TOPCon Silicon Solar Cells

Abstract

This work investigates in detail plating of Ni/Cu/Ag contacts as an alternative metallization approach for industrial bifacial tunneling oxide and passivating contacts (i-TOPCon) silicon solar cells. We have achieved a 23.3 % champion cell efficiency on a front and rear plated bifacial TOPCon silicon solar cell on industrial precursors on a 9 busbar design reaching the same mean efficiency level (Ș = 23.0 %) as industrially processed identical screen printed references. Further, plating metallization demonstrates the potential to contact poly-Si layer thicknesses below 100 nm with reasonable J0,met. The substitution of printed silver by plated copper leads to a significant reduction in the cost of ownership of the metallization backend for i-TOPCon solar cells of about 7.38 $ct/wafer. The integration of plated Ni/Cu/Ag contacts enables a reduction in Ag consumption of about 19.7 t/Gigawatt production capacity compared to screen printing metallization.