Evaluation of TOPCon technology on large area solar cells

Passivating contacts, like TOPCon or poly-Si/SiOx, have pushed the efficiency of crystalline silicon (c-Si) solar cells notably. Currently, the world-record efficiency of 25.7% for a both-sided contact solar cell has been achieved by an n-type solar cell featuring a selective boron front emitter and a passivating rear contact (TOPCon). Like the 25%-efficient PERL cell, this record cell was realized on a small area of 2x2 cm² using lab processes, like photolithography and evaporation of metal contacts. This paper addresses the first steps towards the realization of a large area TOPCon cell by industry-relevant fabrication steps. The scope of this paper lies on the application of laser ablation and NiCu plating to a 1.5mm deep, 140 O/sq boron-diffused emitter. The 10x10 cm² cell yielded an efficiency of 22.9%.