THE CHARACTERISTICS OF AN IN0.5GA0.5P AND IN0.5GA0.5P/GAAS HETEROJUNCTION GROWN ON A (100) GAAS SUBSTRATE BY LIQUID-PHASE EPITAXY

The growth of a high-quality In0.5Ga0.5P/GaAs heterostructure on a (100) GaAs substrate by liquid-phase epitaxy is demonstrated. This has been achieved by controlling the vaporizing time of phosphorus after the melt saturation procedure. The photoluminescence spectra of In0.5Ga0.5P/GaAs heteroepitaxial layers show that the major residual acceptor impurity is either carbon or silicon. The measured values of the conduction-band discontinuity DELTA-E(c) and the fixed interface charge density sigma(i) for a In0.5Ga0.5P/GaAs heterostructure are 110 meV and 1 x 10(11) cm-2, respectively. Only one electron trap with a thermal activation energy of E(a) = 0.32 eV, which is thought to be related to the anion vacancy, is found in Sn-doped In0.5Ga0.5P (n approximately 1 x 10(17) cm-3) layers.