Accelerated publication 23.5% efficient silicon solar cell

The passivated emitter and rear locally diffused cell structure has been redesigned and has yielded independently confirmed one-sun eficiencies of up to 23.5%, the highest ever for a silicon cell. A dotted front emitter contact design, PBr3 liquid-source phosphorus diffusions and 400-μm thick 10-cm diameter wafers have contributed to this improvement. Some of the new cells have demonstrated open-circuit voltages of 709 mV with an ‘inverted’ pyramid surface structure, the highest ever for a 23%-efficiency silicon cell. Further improvement is expected in the near future.