Raman-scattering study of the InGaN alloy over the whole composition range

Abstract

We present Raman-scattering measurements on Inx Ga1-x N over the entire composition range of the alloy. The frequencies of the A1 (LO) and E2 modes are reported and show a good agreement with the one-mode behavior dispersion predicted by the modified random-element isodisplacement model. The A1 (LO) mode displays a high intensity relative to the E2 mode due to resonant enhancement. For above band-gap excitation, the A1 (LO) peak displays frequency shifts as a function of the excitation energy due to selective excitation of regions with different In contents, and strong multiphonon scattering up to 3LO is observed in outgoing resonance conditions. © 2005 American Institute of Physics.