Czochralski growth and evaluation of LaMgAl sub (11) O sub (19) based phosphors.

Materials of the general type LaMgAl sub (11) O sub (19) are of interest because of their potential use as laser or phosphor host materials. Because of the complexity of the structure, it is possible to selectively substitute various ions within the lattice while still retaining the basic hexagonal framework. Single crystal LaMgAl sub (11) O sub (19) has been grown by the Czochralski technique. 

Various rare earth ions with a La sup (3+) site substitution level of up to 5% were prepared, as well as several transition metal ions with a Mg sup (2+) site substitution level of up to 40%. The cathodoluminescence performance of Mn sup (2+) doped LaMg Al sub (11) O sub (19) was maximized at about 20% substitution of the Mg sup (2+) with Mn sup (2+) in the melt. 

The cathodoluminesence emission spectrum at the high levels of Mn sup (2+) substitution is quite similar to that of Mn sup (2+) activated Zn sub 2 SiO sub 4, a broad band emission centered at about 525 nm.