Molecular beam epitaxy and characterization of AlGaAsSb (0.0 ≤ x ≤ 1.0) lattice matched to InAs substrates.

We report the molecular beam epitaxial growth of AlGaAsSb (0.0 ≤ x ≤ 1.0) on undoped, liquid-encapsulated Czochralski, (100) oriented InAs substrates. The degree of lattice mismatch was determined by x-ray diffraction. The lattice matched materials ( y ≈ 0.08 + 0.08 x) were characterized by low temperature photoluminescence, electro-reflectance, and capacitance-voltage measurements. The experimental bandgap energies agree with earlier experimental results for AlGaSb, and also with a self-consistent first principles pseudopotential model. The capacitance-voltage measurements indicate background acceptor concentrations for the unintentionally-doped epitaxial layers of about 2 × 10 cm at x = 1.0 to 5 × 10 cm at x ≈ 0.0. [ABSTRACT FROM AUTHOR]