Band Gap Energy and Its Temperature Dependence of GaInAsSb Quaternary Alloy Grown by Molecular Beam Epitaxy

Abstract

Room temperature band gap energies of MBE-grown Ga1-xInxAs1-ySby have been determined from Fourier transform infrared spectroscopy measurements. The results show good agreement with those calculated from a semi-empirical interpolation method. The temperature dependence of band gap energy has also been investigated for an alloy sample with x=0.247 and y=0.907 at temperatures ranging from 10 to 300 K. While the energy gap varies approximately linearly with temperature for T > 100 K, with a temperature coefficient dEg/dT of -2.63×10-4 eV·K-1, a nearly quadratic T-dependence of the band-gap shift exists for temperatures below the Debye temperature, which consists with that of most of semiconductors.