Georgia Tech researchers develop high-efficiency copper-contacted TOPCon solar cells

Researchers led by the Georgia Institute of Technology have developed a 24.3%-efficient n-type TOPCon solar cell using copper contacts, nearly matching the efficiency of silver-contacted alternatives. By utilizing laser-enhanced contact optimization (LECO) and a novel screen-printable copper paste from Bert Thin Films, the team successfully reduced contact resistance while limiting copper diffusion into the silicon substrate.

This advancement aims to lower manufacturing costs and reduce silver consumption in the solar industry. The copper paste can be processed at approximately 500°C using conventional industrial equipment, a significantly lower temperature than the 700°C typically required for silver pastes.

TOPCon (tunnel oxide passivated contact) technology has become the primary crystalline-silicon platform in the industry. It utilizes n-type silicon wafers with an ultrathin oxide layer and doped polysilicon contacts to reduce carrier recombination, resulting in higher voltage and conversion efficiency compared to traditional PERC architecture.