Temperature-dependentphotoluminescence(PL)measurements were performed for A-plane and C-plane bulk AlN single crystals and epitaxial layers on sapphire. A strong near-band-edge (NBE) emission and deep-level luminescence were observed. At low excitations, the emission spectra are dominated by free and bound excitonic transitions and their LO-phonon replicas. At high excitations, the broadening and redshift of the NBE band is attributed to dense electron–hole plasma formation. The PL spectra differences of bulk single crystals and epilayers is explained by the electron–hole plasma expansion peculiarities.
Published in Applied Physics Letters, Volume 81, Issue 15, 2002, pages 2755-2757.
©Applied Physics Letters 2002, American Institute of Physics (AIP).
Kuokstis, E., Zhang, J., Fareed, Q., Yang, J. W., Simin, G., Khan, M. A., Gaska, R., Shur, M., Rojo, C., & Schowalter, L., (30 September 2002). Near-Band-Edge Photoluminescence of Wurtzite-Type AlN. Applied Physics Letters, 81 (15), 2755-2757. http://dx.doi.org/10.1063/1.1510586