Growth and characterisation of dilute antimonide nitride materials for long-wavelength applications

The addition of small amounts of nitrogen to III–V semiconductors leads to a large degree of band gap bowing, giving rise to band-gaps smaller than in the associated binary materials. The incorporation of active nitrogen has been previously demonstrated for InNxSb1−x (x⩽0.7%) and GaNxSb1−x (x⩽1.75%) material; however, the as-grown carrier concentrations precluded incorporation into a device structure. Here we report the reduction in the as-grown carrier concentration in InNSb by annealing, whilst retaining the active nitrogen content. FTIR absorption measurements show the first direct experimental evidence of narrowing of the InSb bandgap due to nitrogen incorporation. As an alternative route to defect reduction and device compatible material we report on the growth of Ga1−yInyNxSb1−x with 0⩽y⩽30% and x=1.6±0.2% and demonstrate near lattice matching of the material to GaSb.