Tunnel Oxide Passivated Contact (TOPCon) Solar Cells

TOPCon solar cells featuring a poly silicon-based passivating contact are about to become the new standard in c-Si solar cell mass production. The lower recombination loss compared to PERC solar cells enabled by the TOPCon technology results in higher V OC and improved FF , which is impressively demonstrated by device performances in the range of 26% and above. These TOPCon solar cells are usually fabricated on n-type wafers with a boron-diffused front side emitter and n-doped TOPCon layer at the rear surface, which acts as a passivating electron contact. In this chapter, different aspects of this technology are discussed, such as the basic concept, processing-related aspects as well as the application to different solar cell designs with a special focus on industrial TOPCon solar cells.