Lessons Learnt: Hydrogenated Bifacial PERL Silicon PV Cells with Laser Doping and Plated Contacts

Record 22.6% efficient PERC solar cells use screen-printing, requiring expensive silver and aluminium pastes. PERC cells also have significant metal/silicon interface recombination, high metal shading losses and are generally plagued by light-induced degradation (LID), which significantly affects performance and therefore increases costs. Transforming PERC into PERL in the lab through improved metal/silicon interface doping, increased efficiencies from 22% to 25%. This project will address the performance and cost limitations of current PERC technology by enabling the transformation of industrial p-type solar cells to a PERL structure using proven technologies. The aim of the project is to develop a breakthrough low cost, high-efficiency PERL cell technology and innovative, highthroughput commercial production processes and equipment.

This project will build on the successful outcome of three ARENA projects to develop the next generation high-efficiency solar cell. The work in the first 18 months of the project has focused on the development of integration of the three technologies. Thisincludesthe development of an AlOx based p-type laser doping process, the following metal plating process, the incorporation of advanced hydrogenation at different cell process steps for the passivation of laser-induced and light-induced defects, and PERL cell fabrication using commercial grade p-type wafers. A 19.8% efficient cell device integrating the three technologies has been made.