Effects of Growth Temperature on the Compositions of GaAsSb/AlAsSb Epitaxial Layers Grown on GaAs Substrates

Sb-based III–V semiconductor materials are crucial for various applications in the short-wave and midwave infrared spectral ranges. However, epitaxial growth involving multiple group-V elements remains challenging because of their strong dependence on growth temperatures. In this work, we investigate the epitaxial growth of GaAsSb/AlAsSb layers on GaAs substrates under varying Sb fluxes and growth temperatures. We first identify an optimal growth window for AlAsSb to be between 580 and 620 °C, where smooth morphology and well-defined X-ray diffraction peaks are obtained. A systematic growth temperature study from 535 to 635 °C shows that the maximum Sb incorporation occurs at 585 °C. We additionally examine the different Sb incorporation rates and find that Al-containing layers incorporate significantly less Sb than their Ga-containing counterparts. This systematic study clarifies the temperature- and flux-dependent incorporation mechanisms in the GaAsSb/AlAsSb system and provides important details for the growth of high-quality GaAsSb and AlAsSb layers on GaAs for infrared photonic and optoelectronic applications.