T. Sugiura et al., Raman scattering study of InGaN grown by metalorganic vapor phase epitaxy on (0001) sapphire substrates, JPN J A P 1, 40(10), 2001, pp. 5955-5958
We have studied the asymmetric broadening of the Raman spectra of InxGa1-xN
grown on sapphire substrates with the aid of the spatial correlation model
. The asymmetric broadening of the E, phonon mode is enhanced in the region
of immiscibility by increasing the indium molar fraction. The correlation
length, which corresponds to the decay length of the E-2 phonon mode, was e
stimated for the first time. It was on the order of 6-10 rim, which is on t
he same order of magnitude as the size of the columnar structure suggested
by transmission electron microscope analyses.