Luminescent properties of rare-earth ion doped yttrium silicate thin film phosphors for a full-colour display

Abstract

In this paper, we report our results on the sol–gel preparation and spectral properties of (RExY1−x)2SiO5 (RE3+ = Eu3+, Tb3+, Ce3+, x = 0.005, 0.01, 0.02, 0.03 and 0.05) thin films. Effects of annealing temperatures on the thin films structure and optical properties, including luminescence, decay kinetics and CIE colour coordinates have been investigated. Upon exposure to the UV source, films containing Eu3+ and Tb3+ have exhibited bright red- and green-phosphorescent colours, due to the prominent transitions of 5D0→7F2 at 613 nm of Eu3+ and 5D4→7F5 at 543 nm of Tb3+ arising because of the intra-4f n electronic transitions, respectively. The photoluminescence spectrum of (CexY1−x)2SiO5 film mainly shows a broader emission band at 488 nm, which originates from the 5d→4f electron transitions of Ce3+. Luminescence mechanisms of these phosphor thin films have been discussed in detail.