Data for Gallium-doped silicon for high-efficiency commercial passivated emitter and rear solar cells

We have assessed the carrier lifetime potential of such Czochralski‐grown wafers in dependence of resistivity, finding effective lifetimes well into the millisecond region without any gettering or hydrogenation processing, thus demonstrating one advantage over boron doped silicon.

Secondly, we monitor the stability of gallium doped PERC cells under illumination (> 3000 h in some cases) and detect anomalous behaviour. While some cells are stable, others exhibit a degradation then recovery, reminiscent of light and elevated temperature induced degradation (LeTID) observed in other silicon materials. Surprisingly, cells from one ingot exhibit LeTID‐like behaviour when annealed at 300 °C but near stability when not annealed, but, for another ingot, the opposite is observed.