Structural and optical characterization of type II In0.14Ga0.86As0.13Sb0.87/GaSb heterostructure doped with zinc grown by liquid phase epitaxy

•Zn-doped InGaAsSb epilayers were grown by liquid phase epitaxy on Te-doped GaSb.•It has investigated the effect of high doping by Zn in a wide range in LPE InGaAsSb.•The crystalline quality of the InGaAsSb layers is good in investigated doping range as was obtained by Raman scattering.•LPE InGaAsSb has good optical properties as was obtained by 14K photoluminescence. In0.14Ga0.86As0.13Sb0.87 quaternary solid solutions lattice-matched to GaSb (001) substrates were grown by liquid phase epitaxy, which were intentionally doped with Zn in a wide range. Two main vibrational bands are observed in their Raman spectra over the doping range investigated. The assignment of the observed modes to GaAs-like and (GaSb+InAs)-like mixture modes is discussed. The comparison of the experimental results with obtained ones by the modified random-element isodisplacement (MREI) model allows to confirm that the bands correspond to the vibrational modes associated with longitudinal- and transverse-optical (LO and TO) modes of the binary compounds GaAs and (GaSb+InAs). The low-temperature photoluminescence (LT-PL) of p-type InxGa1−xAsySb1−y was studied as a function of zinc concentration added to the melt solution. Low temperature photoluminescence spectra show the presence of an emission band that has been related to radiative emission involving Zn-acceptors. For low carrier concentration, the photoluminescence line shape could be explained in terms of a direct transition following a simple k-selection rule. For degenerate concentrations, however, it is properly interpreted in terms of non-k-conserving transitions which arise from indirect recombination of holes in a highly filled valence band.