Industrial LCP selective emitter solar cells with plated contacts

Abstract

The investigation of different selective emitter (SE) approaches is a current trend in solar cell manufacturing. The incorporation of a local high phosphorous doping underneath the front contact grid allows for the use of high-sheet resistance illuminated emitters that combine low recombination and improved blue response. Further efficiency increase compared to the standard screen-printed solar cell is achieved via plated contacts that feature better aspect ratio and optical properties, higher line conductivity and smaller width compared to screen-printed contacts. In this paper we present detailed technological requirements for next-generation front side metallization as well as experimental results of the RENA high-efficiency metallization cluster consisting of Laser Chemical Processing (LCP) and Ni-Ag light-induced plating (LIP). It becomes clear that efficiency on cell level is not the only figure of merit for a successful product and that the combination of SE with plating has a much higher potential for increasing cell efficiency than the metallization of SE via screen-printing.