Importance of Long-lifetime n-GaInP for High-efficiency GaInP Solar Cells Grown by MBE

We present a systematic photoluminescence (PL) study on the effects of doping and rapid thermal annealing (RTA) conditions on n- and p-GaInP double-heterostructures (DHs) grown by molecular beam epitaxy (MBE). The steady-state photoluminescence (SSPL) intensity of lightly doped n- and p-GaInP both improve significantly after RTA, while in contrast, heavily doped n-GaInP degrades sharply with RTA. Front-junction (FJ) GaInP cells with this heavily doped n-GaInP emitter were severely damaged after RTA, as expected. Replacing the emitter with lightly doped n-GaInP may help to alleviate the degradation and lead to improved MBE-grown GaInP solar cells.