Growth of GaAs and InGaAs by MOCVD using a tertiarybutylarsine source

Abstract

The metalorganic chemical source, tertiarybutylarsine (TEA) has been investigated for its possible use as precursor in the process of metalorganic chemical vapour deposition (MOCVD). The electrical and optical properties of epilayers are characterized by Hall measurement, X-ray diffraction (XRD), scanning electron microscopy (SEM), photoreflectance (PR) and photoluminescence (PL) spectra. The best quality of GaAs epilayers are grown at 150 Torr with a V/III ratio of 10.82, and the growth temperature is 600 degrees C. The full width at half maximum (FWHM) of 10 K PL is as narrow as 7.27 meV, the mobility is 7128 cm2 V-1 s-1 and the carrier concentration 8*1015 cm-3 at 300 K. The growth rate of GaAs epilayers is 0.74 mu m h-1, and broadening parameter Gamma of 300 K PR is 11.35 meV. When growing InGaAs heteroepitaxial layers, the growth rate of InGaAs epilayers is 0.625 pm h-1. When the composition x is increased from 0.045 to 0.16, the value of FWHM for PL spectra is increased from 12.35 meV to 33.28 meV. For the Raman spectra, when the indium composition is increased from 0.0455 to 0.25, the frequency of the GaAs-like LO mode is shifted to a lower one.