Er-doped alumina crystalline films deposited by radiofrequency magnetron co-sputtering

► Radiofrequency magnetron sputtering deposition can be used for obtaining Er-doped dielectric film. ► With a suitable choice of the preparation parameter, rf magnetron sputtering allows to obtain Er-doped crystalline alumina films. ► The Er-doped crystalline alumina films show an intense infrared luminescence at 1.54 μm of wavelength. ► The films show interesting changes of the 1.54 μm emission band shape as a function of the optical activation annealing temperature.