Single‐Crystal Rare‐Earth‐Doped Yttrium Orthosilicate Phosphors

This is a study of a group of Czochralski grown rare-earth-doped Y/sub 2/SiO/sub 5/ single-crystal cathodoluminescent phosphors. Such dopants as Ce/sup 3+/, Tb/sup 3+/, Eu/sup 3+/, Sm/sup 3+/, Tm/sup 3+/, Gd/sup 3+/, and some of their combinations were investigated. Activation by (Ce/sup 3+/ + Gd/sup 3+/), (Tb/sup 3+/ + Gd/sup 3+/), and by (Tb/sup 3+/ + Eu/sup 3+/) produced the most efficient blue, green, and red phosphors, respectively. In comparison with our previous best garnet single-crystal phosphor system, the Y/sub 2/SiO/sub 5-/based blue, green, and red phosphors are by factors 12.7, 1.23, and 0.7 brighter, respectively. Gd/sup 3+/:Y/sub 2/SiO/sub 5/ was shown to be an efficient single line (313 nm) emitting phosphor of very high spectral brightness in UV.