EuGa2S4 and CaGa2S4:Ce were prepared by a method of the decomposition
of metal dimethyldithiocarbamates which provides a simple and safe tec
hnique desired for the phosphor production. W-irradiation of such EuGa
2S4 and CaGa2S4:Ce (in the Ce/Ca=1/20 ratio) polycrystallines gave gre
en and blue emission with high yield, as exemplified by relative yield
s of 0.17 and 0.84 against a commercially available Y2SiO5:Ce blue pho
sphor at room temperature respectively.