Time-resolved photoluminescence of MBE-grown 1 eV GaAsSbN for multi-junction solar cells

GaAsSbN is an alloy that can achieve 1 eV bandgap lattice-matched to GaAs. The alloy may be an interesting alternative to the more common GaInNAs(Sb) used in high efficiency multi-junction solar cells, as GaAsSbN shows enhanced nitrogen incorporation. We present photoluminescence (PL) and time-resolved photoluminescence (TRPL) measurements taken using a streak camera for a range of double-heterostructure samples. Layers of different thickness and doping are investigated. Effective minority carrier lifetimes are 200-450 ps at room temperature. A difference in behaviour with dopant polarity is noted, with p-type material exhibiting longer minority carrier lifetimes.