Electronic band structure of AlGaInP grown by solid-source molecular-beam epitaxy

The compositional dependence of the electronic band structure of (AlxGa1−x)0.52In0.48P lattice matched to GaAs is reported. Epitaxial layers, grown by solid-source molecular-beam epitaxy, with excellent structural and optical quality are obtained over the whole compositional range. Optical spectroscopic techniques are used to study the electronic band structure as a function of composition. The low-temperature, direct excitonic band gap is found to be given by Eg(x)=1.979+0.704x eV and the lowest band gap becomes indirect for xc=0.50±0.02. The low-temperature excitonic direct band gap of Al0.52In0.48P is measured to be 2.680 eV.