Narrowband ultraviolet light emission from AlGdN polycrystalline thin films

We have investigated the narrowband ultraviolet (UV) emission characteristics of rare-earth nitrides A(1-x)Gd(x)N grown by reactive magnetron sputtering in an ultra-pure process. Gd3+ ions in the alloy films efficiently emit UV luminescence at 317 nm. The transition occurs from the P-6(7/2) excited state to the S-6(7/2) ground state in the 4f orbital. The crystallographic properties of the alloy phosphor thin film are sensitive to the growth temperature. With a decrease in the growth temperature, the emission efficiency increases. Furthermore, introducing a buffer layer before growing the phosphor layer has been found to enhance the emission intensity considerably.