Copper Light Induced Plating on Silver Screen-Printed Contacts of Silicon Solar Cells

Abstract

Copper light-induced plating onto the surface of existing screen-printed silver contacts of industrial Silicon solar cells was studied. Electrolyte and cell-in-electrolyte systems were analyzed to determine the optimal plating conditions. Two methods of protection of a cell rear side from dissolution (by insulating and by applying electrical potential) are compared. It was found that the parasite cells are created in the plating bath due to the difference of the redox potentials of silver, copper and aluminum. Previously reported equilibrium conditions for terminal and anode – rear side voltage must be modified to compensate the parasite cell current. The solar cell efficiency gain is found to be a nonmonotonic function of deposition rate and duration. Absolute solar cell efficiency was improved by 1,53%.