Blue-emitting Eu2+-doped calcium aluminate phosphor thin films were obtaine
d using the pulsed laser deposition technique with post annealing. As-depos
ited films were amorphous and showed weak red Eu3+ photoluminescence (PL).
By annealing in reducing atmosphere (N-2/H-2:2% mixed gas) at 950 degreesC
for 3 h, the film was crystallized and showed a PL emission band peaking at
about 447 nm, which originated from the 4f(6)5d to 4f(7) transition of Eu2
+ ion. It is considered that the deposited film consists mainly of CaAl2O4
and partly of other binary compounds of the CaO-Al2O3 system. It was determ
ined that the PL intensity of Eu2+ in CaAl2O4 can be controlled by the lase
r fluence, target-substrate distance and injection gas.