JIANG Hong, SONG Hang, MIAO Guo-qing. Lattice Vibrations of MOCVD-Ga<sub>x</sub>In<sub>1-x</sub>As<sub>y</sub>P<sub>1-y</sub>/InP DBRs Structures[J]. Chinese Journal of Luminescence, 2006,27(6): 967-970
JIANG Hong, SONG Hang, MIAO Guo-qing. Lattice Vibrations of MOCVD-Ga<sub>x</sub>In<sub>1-x</sub>As<sub>y</sub>P<sub>1-y</sub>/InP DBRs Structures[J]. Chinese Journal of Luminescence, 2006,27(6): 967-970DOI:
Lattice Vibrations of MOCVD-GaxIn1-xAsyP1-y/InP DBRs Structures
/InP Distributed Bragg reflectors(DBRs) are investigated by micro-Raman scattering techniques. The used DBRs samples were formed with Ga
0.4
In
0.6
As
0.85
P
0.15
/InP alternative layers grown on the S-doped high quality (100) InP substrates in an atmospheric or low pressure metal organic chemical vapor deposition(MOCVD) system made up in our laboratory. The lattice constant and composition parameters(
x
y
) were determined using double crystal X-ray diffraction
scanning electronic microscope-photoelectron spectra and photoluminescence(PL) measurements. Raman spectra were measured at room temperature using the 488 nm line of Ar ion laser as an exciting source. The Raman signal was collected in the near back-scattering configuration and analyzed with a monochromator. The Raman spectra exhibit three major modes of vibrations in the quaternary alloy Ga
0.4
In
0.6
As
0.85
P
0.15
grown on the InPsubstrates. They are attributed to InAs-like
GaAs-like and GaInP-like
respectively. The Raman spectra line-shape of the three major modes of vibrations clearly changed with the increasing of period number of DBR. The intensity of the InAs-like vibration is not changed
but its full width at half-maximum(FWHM) narrowed
the peak value location moved in the direction of the low-frequency. The intensity of the GaAs-like and GaInP-like gradually weaken. Ratio of intensities of InAs- and GaAs-like vibrations increased with the increasing of period number of DBR. The quaternary alloy Ga
0.4
In
0.6
As
0.85
P
0.15
was in the region of immiscibility. It was found that the surfaces of the samples grown in the region of immisicibility are rough. The interface quality between the Ga
0.4
In
0.6
As
0.85
P
0.15
and InPwas effected. The restrictive effect of the phonon in the Raman scattering investigations showed that the non-integrity crystalloid appeared during the growth of the multi-layer structure.