dc.description.abstract | Raman scattering spectroscopy was used to measure and analyze the lattice
vibrations in some quaternary Ga1-xInxAsySb1-y alloys with low (In, As) contents, (0.03 <x<
0.12 and 0.03 <y< 0.10). The layers were grown by liquid phase epitaxy on (001) GaSb
substrates at 540 °C. High Resolution X-Ray Diffraction results showed profiles associated
with a quaternary layer lattice matched to the GaSb substrate as obtained from the (004)
reflection. The experimental diffractograms were simulated to estimate alloy composition,
thickness and lattice mismatch of the layer. Raman scattering results show phonon frequencies
associated to the TO and LO GaAs-like modes as well as GaSb+InAs-like mode, which are
characteristic of this quaternary alloy. The As content dependence of the phonon frequency
measured in this alloy for low (In, As) contents agree well with the modified Random-Element
Isodisplacement (REI) model and also with other available experimental reports. This method
can also be used to estimate alloy compositions for this kind of quaternary alloys. | |