GROWTH OF GAAS AND INGAAS BY MOCVD USING A TERTIARYBUTYLARSINE SOURCE

The metalorganic chemical source, tertiarybutylarsine (TBA) has been i nvestigated for its possible use as precursor in the process of metalo rganic chemical vapour deposition (MOCVD). The electrical and optical properties of epilayers are characterized by Hall measurement, x-ray d iffraction (XRD), scanning electron microscopy (SEM), photoreflectance (PR) and photoluminescence (PL) spectra. The best quality of GaAs epi layers are grown at 150 Torr with a V/III ratio of 10.82, and the grow th 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 cm(2) V-1 s (-1) and the carrier concentration 8 x 10(15) cm(-3) at 300 K. The gro wth rate of GaAs epilayers is 0.74 mu m h(-1), and broadening paramete r Gamma of 300 K PR is 11.35 meV. When growing InGaAs heteroepitaxial layers, the growth rate of InGaAs epilayers is 0.625 mu m h(-1). When the composition x is increased from 0.045 to 0.16, the value of FWHM f or 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.