Luminescence distribution of Yb-doped Ca-alpha-SiAlON phosphors

作者：Dierre B; Yuan X L; Hirosaki N; Kimura T; Xie R J; Sekiguchi T^*

来源：Journal of Materials Research, 2008, 23(6): 1701-1705.

DOI：10.1557/JMR.2008.0208

Luminescence properties of Yb-doped Ca-alpha-SiAlON phosphors with composition of Ca1-xYbxSi12-(m+n)Alm+nOnN16-n were investigated by using cathodoluminescence (CL). The ratio of Yb to Ca was kept constant while the host lattice was changed by replacing m+n(Si-N) bonds with m(Al-N) and n(Al-O) bonds. The luminescence of these phosphors consists of three peaks in the ultraviolet (UV), green (VIS), and infrared (IR) regions, which are attributed to the emissions from secondary phases, Yb2+ and Yb3+, respectively. The UV emission depends on the Si/Al ratio: the UV peak is centered at 310 nm for the Si-rich mix and at 360 nm for the Al-rich mix. We have found that Yb exists in the divalent state in alpha-SiAlON and in the trivalent state in the secondary phases.

• 出版日期2008-6