MOLECULAR-BEAM EPITAXY AND CHARACTERIZATION OF ALXGA1-XASYSB1-Y (0.0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-1.0) LATTICE MATCHED TO INAS SUBSTRATES

We report the molecular beam epitaxial growth of Al x Ga1-x As y Sb1-y (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 Al x Ga1-x Sb, 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 × 1015 cm-3 at x = 1.0 to 5 × 1016 cm-3 at x ≈ 0.0. © 1990 AIME.