Analysis of Recombination Processes in 0.5–0.6 eV Epitaxial GaInAsSb Lattice‐matched to GaSb

This work summarizes recent data on minority carrier lifetime in n‐ and p‐type double heterostructures (DHs) of 0.5–0.6 eV GaInAsSb confined with GaSb and AlGaAsSb cap layers. Recombination times were measured by time‐resolved photoluminescence (TRPL) and by optical frequency response (OFR) to sinusoidal excitation. It was shown that one of the mechanisms responsible for interface recombination in GaSb/GaInAsSb/GaSb DHs is thermionic emission of carriers over the heterobarrier. Considerable improvement of carrier confinement was obtained with 1 eV AlGaAsSb cap layers. Optimization of the epitaxial growth resulted in a recombination velocity at GaInAsSb/AlGaAsSb interface as low as 30 cm/s.