Comments on a peak of AlxGa1−xN observed by infrared reflectance

AlxGa1−xN epilayers, grown on c-plane oriented sapphire substrates by metal organic chemical vapour deposition (MOCVD), were evaluated using FTIR infrared reflectance spectroscopy. A peak at ∼850 cm−1 in the reflectance spectra, not reported before, was observed. Possible origins for this peak are considered and discussed.