Screen Printable Copper Pastes for Silicon Solar Cells

The photovoltaic industry has been actively trying to replace silver with copper as the primary metallization material, but concerns around durability have limited deployment. To date, a screen printable copper-based paste that can fire through the SiN antireflective layer has yet to be commercialized. This work details the development of a screen printable copper paste that can be fired in atmospheric belt furnaces; thus, offering manufactures the ability to completely replace Ag without adding any processing costs. The performance and challenges of the copper-based paste are discussed, and accelerated aging tests are applied to copper metallized PERC cells to show the impact of processing conditions on long-term durability.