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GaInAsSb and AlGaAsSb alloys have been grown by organometallic vapor phase epitaxy (OMVPE) using all organometallic sources, which include tritertiarybutylaluminum, triethylgallium, trimethylindium, tertiarybutylarsine (TBAs), and trimethylantimony. Excellent control of lattice-matching both alloys to GaSb substrates is achieved with TBAs. GaInAsSb/AlGaAsSb multiple quantum well (MQW) structures grown by OMVPE exhibit strong 4K photoluminescence with full width at half maximum of 10 meV, which is comparable to values reported for quantum well (QW) structures grown by molecular beam epitaxy. Furthermore, we have grown GaInAsSb/AlGaAsSb MQW diode lasers which consist of n- and p-doped Al0.59Ga0.41As0.05Sb0.95 cladding layers, Al0.28Ga0.72As0.02Sb0.98 confining layers, and four 15 nm thick Ga0.87In0.13As0.12Sb0.88 quantum wells with 20 nm thick Al0.28Ga0.72As0.02Sb0.98 barrier layers. These lasers, emitting at 2.1 µm, have exhibited room-temperature pulsed threshold current densities as low as 1.2 kA/cm2. [ABSTRACT FROM AUTHOR]

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]