Ion-implanted and screen-printed large area 19.6% efficient n-type bifacial Si solar cell

In this paper, we show successful fabrication of high efficiency 19.6 % n-type bifacial solar cells on 239 cm² Cz using ion implantation of boron and phosphorus along with screen printed metallization. A very low emitter saturation current density (J_oe) of 80 fA/cm² was obtained from re- grown SiO₂ caped with SiN_x on a chemically etched boron emitter. It is also shown that 8% metallization can raise the boron emitter J_oe by ~85 fA/cm² and phosphorus BSF J_ob' by ~126 fA/cm². Detailed cell analysis shows that the high base saturation current density (J_ob) is a major performance limiting factor in the 19.6% efficient n-type bifacial cell.