High-quality quaternary AlInGaN epilayers on sapphire

Quaternary AlInGaN epilayers were grown on sapphire substrates by atmospheric pressure metalorganic chemical vapour deposition (MOCVD). The characterization data indicate that the grown quaternary AlInGaN epilayers are of high-quality. The influence of indium incorporation on the properties of quaternary epilayers were studied. The PL spectra of the quaternary layers showed narrow full-width at half-maximum (FWHM) values (52 meV) at room temperature, which are comparable to that of GaN. The X-ray rocking curves of quaternary layers for (0004) diffraction exhibited narrow FWHM values ranged from 250 to 280 arcsec. To the best of our knowledge, these are the best results among those published in the literature.