ABSTRACT
Deep level transient spectroscopy, infrared absorption, or photoluminescence (PL) measurements were made on molecular beam epitaxially grown samples of Ga0.80In0.20As0.12Sb0.88, AlAs0.07Sb0.93, and InAs1-xSbx (0.031 < x < 0.192) materials used to develop 2-4 μm quantum well laser structures lattice-matched to GaSb substrates. In addition to five other hole trap levels, a trap with the greatest effect on nonradiative recombination located at 276 meV above the valence band (Ev) was found in the Ga0.80In0.20As0.12Sb0.88 active region material. A DX-like trap was found in the AlAs0.07Sb0.93 cladding material at Ec282 meV. Temperature-dependent absorption measurements made on undoped InAs1-xSbx active region material resulted in the closed-form expression for the energy gap. The measured PL linewidth of the band-to-band transition of InAs1-xSbx is narrower than any previously reported values, indicating the high quality of this material. Furthermore, two shallow impurity levels were resolved at energies 5-7 meV from the band edge.
