Effects of dopant contents on structural, morphological and optical properties of Er doped Ga₂O₃ films

We have investigated structural, morphological and optical properties of erbium (Er) doped Ga₂O₃ films with different Er contents. All the films were deposited on sapphire substrates by pulsed laser deposition. Temperature insensitive pure green luminescence at 550 nm has been demonstrated from these films. No peak shift at 550 nm is found with temperatures ranging from 77 to 450 K. The intensity of the green emission decreases with the increase of temperature, and the normalized intensity of the Er doped Ga₂O₃ films has a smaller variation with temperature compared to Er doped GaN films. These results indicate that Ga₂O₃ is a good host material for Er and potentially for other rare earth elements.