Study of GaAs-Based Dilute Nitride Materials Grown by Liquid Phase Epitaxy

This paper reports on liquid phase epitaxy (LPE) growth and characterization of monocrystalline dilute nitride InGaAs(Sb)N and GaAsSbN layers in view of their photovoltaic applications. To obtain high quality epitaxial layers without phase separation the low-temperature variant of the LPE method is used. The structural characterization of the samples is carried out by means of scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction measurements. The optical bandgap is studied by photoluminescence (PL) spectroscopy at low and room temperature. Surface photovoltage spectroscopy (SPV) is applied to determine the optical absorption edge. Both PL and SPV spectra reveal a decrease of the band gap of GaAsSbN as compared to InGaAs(Sb)N, which is of value for its application in solar cells.