Visible cathodoluminescence of Er-doped amorphous AlN thin films

Abstract

In this report, we demonstrate the observation of visible cathodoluminescence (CL) of Er-doped amorphous AlN films produced by sputtering. Optical transmission studies point out that the films are highly transparent and the band gap is about 5.61 eV. Elemental analysis by Rutherford backscattering spectrometry shows that AlN films are stoichiometric. X-ray diffraction measurements reveal that the films retain the amorphous structure even after annealing in N2 ambient at 1000 °C. The sharp characteristic emission lines in the CL spectra correspond to Er3+ intra-4fn shell transitions and are observed over the temperature range of 9–330 K. The results indicate the suitability of Er-doped amorphous AlN films for light-emitting device applications.