N-Type Bifacial Solar Cells with Laser Doped Contacts

Laser doping is investigated as an alternative to high-temperature furnace diffusions to form contacts on bifacial n-type silicon solar cells. A process is demonstrated in which a single laser step forms both selective heavily doped contact regions and defines a mask for subsequent electro-less metal plating. The integration of the laser doped contacts with solar cell structures is investigated in terms of minority carrier recombination, metal plating and electrical properties of finished devices. The process is shown to be a promising alternative to furnace diffusions and may provide a more industrially applicable technique for fabricating bifacial n-type solar cells