Abstract
The temperature dependence of photoluminescence (PL) of high-quality unintentionally doped GaSb layers grown from Ga- and Sb-rich solutions by liquid-phase epitaxy has been studied. The photoluminescence was demonstrated with carrier concentrations 6-8×10 15 cm 3 . The low temperature photoluminescence measurements indicated that the transitions of excitons bound to donors and neutral acceptors dominated, and the intensity of a weaker band relative to native antisite defects was substantially reduced. When the temperature increased, the intensity of the lines associated with the bound-exciton transitions was rapidly quenched, and the free-electron-to-free-hole transition became dominant. A free exciton transition with a narrow FWHM of 0.4 meV was observed for the the sample grown from the Sb-rich solution at the 16 K PL spectrum. The temperature dependent band gap in GaSb layers obtained from the PL peak energy varied as 0.813-[1.08×10 -4 T 2 /(T-10.3)] eV.