Growth and photoluminescence of GaSb and ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$${\mathrm{In}}_{\mathit{x}}$${\mathrm{As}}_{\mathit{y}}$${\mathrm{Sb}}_{1\mathrm{-}\mathit{y}}$ grown on GaSb substrates by liquid-phase electroepitaxy

We report on the liquid-phase electroepitaxial (LPEE) growth of GaSb and ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{In}}_{\mathit{x}}$ ${\mathrm{As}}_{\mathit{y}}$ ${\mathrm{Sb}}_{1\mathrm{-}\mathit{y}}$ alloys on undoped (100) GaSb substrates. Alloys with room-temperature photoluminescence peak wavelengths as long as 2.32 μm have been grown. These layers were assessed by x-ray diffraction, energy-dispersive x-ray analysis, and low-temperature Fourier-transform photoluminescence (PL), with emphasis on the latter. The variation in the low-temperature photoluminescence bands as a function of the alloy composition has been investigated. The low-temperature (4.5 K) PL spectra of the alloys exhibited narrow peaks with full width half maxima in the range 3–7 meV, indicating an excellent quality of the LPEE-grown epilayers. The temperature and intensity dependences of the PL spectra were investigated to identify the nature of the recombination processes.